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Krok 1 Paper with Explanation
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1. A 62-year-old woman diagnosed with arterial hypertension was prescribed an angiotensin-converting enzyme inhibitor. In this case, the production of a certain bioactive substance will decrease. Name this substance:

A. Angiotensin I

B. Renin

C. Angiotensinogen

D. Angiotensin II

E. Noradrenaline

Answer: Angiotensin II


Angiotensin II is a bioactive substance that is responsible for constricting blood vessels and increasing blood pressure, so by inhibiting its production, the ACE inhibitor helps to lower blood pressure.  

Angiotensin I, renin, angiotensinogen, and noradrenaline are all involved in the renin-angiotensin-aldosterone system (RAAS) pathway, which regulates blood pressure and fluid balance in the body.

2. Examination of a patient in a clinical diagnostic laboratory detected that the activity of the LDH 1, isoenzyme is high in the patient’s blood serum. Such clinical and laboratory findings are characteristic of the pathology of the following internal organ:

A. Kidneys

B. Pancreas

C. Heart

D. Skeletal muscles

E. Liver

Answer: Heart


LDH (lactate dehydrogenase) is an enzyme that is present in many tissues in the body, including the heart, liver, kidney, skeletal muscle, and pancreas. However, different tissues contain different isoenzymes of LDH, which are distinguished based on their electrophoretic mobility.  

LDH-1 is the predominant isoenzyme found in the heart, and an increase in its activity in the blood serum is typically associated with cardiac damage or injury, such as from a heart attack or myocarditis. Therefore, the clinical and laboratory findings of high LDH-1 activity in the blood serum are characteristic of heart pathology.

3. A patient diagnosed with polyneuropathy was Prescribed vitamin B 1. Name the coenzyme form of this vitamin:

A. Nicotinamide adenine dinucleotide phosphate

B. Pyridoxal phosphate

C. Thiamine diphosphate

D. Flavin adenine mononucleotide

E. Tetrahydrofolate

Answer: Thiamine diphosphate


Vitamin B1, also known as thiamine, is an essential nutrient that is required for the proper functioning of the nervous system. Thiamine functions as a coenzyme in the body, which means that it helps enzymes to catalyze important biochemical reactions.  

The coenzyme form of thiamine is thiamine diphosphate (TDP), which is involved in several metabolic pathways, including the breakdown of glucose for energy production. In patients with polyneuropathy, which is a disorder that affects multiple peripheral nerves, supplementation with vitamin B1 (in the form of TDP) may help to improve nerve function and reduce symptoms.

4. A 5-year-old child became acutely ill and developed fever, intoxication, and hemorrhagic skin rash. The child died of acute adrenal insufficiency. Autopsy revealed morphological changes caused by the severity of DIC syndrome and endotoxic shock. On the skin, there are necrotic foci, diapedetic hemorrhages, and fibrin thrombi in the dermal vessels. The adrenal glands have massive hemorrhages. What disease can be characterized by these changes?

A. Measles

B. Meningococcemia

C. Influenza

D. Scarlet fever

E. Typhus

Answer: Meningococcemia


Meningococcemia is a severe bacterial infection caused by the bacterium Neisseria meningitidis, which can lead to sepsis, DIC (disseminated intravascular coagulation) syndrome, and endotoxic shock.   The symptoms of meningococcemia can include fever, chills, headache, nausea, vomiting, muscle and joint pain, and a hemorrhagic skin rash (petechiae and purpura).

In severe cases, the infection can lead to acute adrenal insufficiency, which can be fatal.   The autopsy findings in this case, including the hemorrhagic skin rash, DIC, and massive hemorrhages in the adrenal glands, are characteristic of meningococcemia.  

Measles, influenza, scarlet fever, and typhus can also cause fever and rash, but they typically do not lead to the severe hemorrhagic and shock-related complications seen in meningococcemia.

5. A man with a kidney transplant was receiving immunosuppressive therapy. Died of intoxication. Morphological examination detects giant cells with large nuclei and a light border, resembling an owl’s eye, in the patient’s lungs, kidney, and pancreas. What infectious disease can be characterized by these changes?

A. Leprosy

B. Cytomegalovirus infection

C. Tuberculosis

D. Plague

E. Syphilis

Answer: Cytomegalovirus infection


Cytomegalovirus (CMV) is a common viral infection that can cause serious complications in immunocompromised individuals, such as those who have received a kidney transplant and are receiving immunosuppressive therapy.   The symptoms of CMV infection can vary widely, from mild fever and fatigue to more severe complications, such as pneumonia, hepatitis, and encephalitis.

In some cases, CMV can cause the formation of inclusion bodies in infected cells, which are characteristic of the virus.   These inclusion bodies are often described as resembling an owl’s eye, due to their appearance of a central dark area surrounded by a clear halo.

In this case, the presence of giant cells with owl’s eye inclusion bodies in the lungs, kidney, and pancreas suggests that the patient had disseminated CMV infection, which may have contributed to their fatal intoxication.  

Leprosy, tuberculosis, plague, and syphilis can all cause granulomatous inflammation and tissue damage, but they typically do not produce the characteristic owl’s eye inclusion bodies seen in CMV infection.

6. A 44-year-old man developed a sharp drop in blood pressure before his death. Autopsy of the body shows an aortic arch aneurysm up to 10 cm in diameter. The aortic intima in its ascending part and in the arch looks wrinkled and is exfoliated; between the intima and the aortic media there are blood clots. In the aortic media, microscopy detects large foci of infiltration with lymphoid, plasma, and epithelioid cells, destruction of elastic fibers, proliferation of connective tissue, and vasculitis vasa vasorum. What disease can be characterized by these changes?

A. Nodular polyarteritis

B. Atherosclerotic aortic aneurysm

C. Syphilitic mesaortitis

D. Nonspecific aortoarteritis

E. Rheumatic aortitis

Answer: Syphilitic mesaortitis


Syphilitic mesaortitis is a rare complication of untreated syphilis infection, which can cause inflammation and damage to the walls of the aorta and other large arteries.   The characteristic findings on autopsy in this case, including the aortic arch aneurysm, exfoliation of the aortic intima, blood clots, lymphoid and plasma cell infiltration, destruction of elastic fibers, and vasculitis of the vasa vasorum, are all consistent with syphilitic mesaortitis.  

Nodular polyarteritis, atherosclerotic aortic aneurysm, nonspecific aortoarteritis, and rheumatic aortitis can also cause inflammation and damage to the aortic wall, but they typically present with different histopathological features and are not associated with syphilis infection.

7. Only one of these statements about the extraordinary excitation occurring in the ventricular myocardium is correct. Name the correct statement:

A. It increases the rate of excitation conduction in the working cardiomyocytes.

B. It increases the automaticity of the sinoatrial node

C. It decreases the rate of excitation conduction in the working cardiomyocytes

D. It decreases the automaticity of the sinoatrial node

E. It has no effect on the automaticity of the sinoatrial node

Answer: It has no effect on the automaticity of the sinoatrial node


Extraordinary excitation, also known as delayed afterdepolarizations, can occur in ventricular cardiomyocytes as a result of certain physiological and pathological conditions. During this process, the membrane potential of the cardiomyocyte becomes depolarized to a level that can trigger an action potential and cause an abnormal contraction.

This can lead to arrhythmias, such as ventricular tachycardia and fibrillation.   One of the effects of extraordinary excitation is to slow down the rate of excitation conduction in the working cardiomyocytes, which can contribute to the development of arrhythmias.  

It does not directly affect the automaticity of the sinoatrial node, which is responsible for generating the electrical impulses that initiate each heartbeat. However, arrhythmias resulting from extraordinary excitation can potentially affect the normal rhythm of the heart and lead to changes in the heart rate.

8. Autopsy of the fetus revealed an epidural hematoma caused by the rupture of the falciform sinus and cerebellar tentorium. Such injury can result from a pathology occurring during the following developmental stage:

A. Postnatal

B. Antenatal

C. Progenesis

D. Intranatal

E. Perinatal

Answer: Antenatal


An epidural hematoma is a collection of blood between the skull and the outermost layer of the meninges, called the dura mater. In this case, the autopsy revealed an epidural hematoma in the fetus, which means there was bleeding in the space between the skull and the dura mater.  

The rupture of the falciform sinus and cerebellar tentorium suggests that the bleeding occurred in the area of the falx cerebri (a fold of dura mater that separates the two cerebral hemispheres) and the tentorium cerebelli (a fold of dura mater that separates the cerebrum from the cerebellum).  

Since the fetus underwent an autopsy, it means that the injury occurred before birth. “Antenatal” refers to the period of time before birth, specifically during fetal development.

9. A patient with influenza has fever, dyspnea, and tachycardia How will the oxygen affinity of Hb change under such conditions?

A. Remain unchanged

B. Decrease

C. First increases, then decreases

D. Increase

Answer: Decrease


Influenza is a viral respiratory infection that can cause various symptoms, including fever, dyspnea (difficulty breathing), and tachycardia (rapid heartbeat). When the body experiences these symptoms, it undergoes certain physiological changes in response to the infection.  

One of the responses to infection and tissue hypoxia (insufficient oxygen supply) is an increase in the production of certain compounds called cytokines. These cytokines, such as interleukin-1 (IL-1) and tumor necrosis factor-alpha (TNF-alpha), can have an effect on the oxygen-carrying capacity of hemoglobin (Hb) in red blood cells.  

Under the influence of these cytokines, the oxygen affinity of hemoglobin decreases. This means that hemoglobin has a reduced ability to bind and carry oxygen efficiently. As a result, oxygen is more readily released from hemoglobin to the tissues, aiding in oxygen delivery to meet the increased demand caused by the infection and associated symptoms.

10. A patient died of chronic renal failure. The patient’s pericardial leaflets are dull-colored and have gray and thin filamentous coating. What pathological process occurred in the pericardium?

A. Purulent inflammation

B. Catarrhal inflammation

C. Proliferative inflammation

D. Serous inflammation

E. Fibrinous inflammation

Answer: Fibrinous inflammation


In this scenario, the patient who died had chronic renal failure, and the pericardial leaflets (part of the pericardium, the membrane surrounding the heart) are described as dull-colored, with a gray and thin filamentous coating. These findings suggest an abnormality in the pericardium.  

Fibrinous inflammation is a type of inflammation characterized by the exudation of fibrin-rich fluid into the affected tissue. Fibrin is a protein involved in blood clotting, and its presence indicates the activation of the coagulation cascade.  

In the context of the pericardium, fibrinous inflammation can occur due to various causes, including infections, autoimmune diseases, and certain systemic conditions. In chronic renal failure, there can be an accumulation of waste products and imbalances in the body, leading to inflammation and tissue damage.  

The description of the pericardial leaflets having a gray and thin filamentous coating suggests the presence of fibrin in the pericardium, indicating fibrinous inflammation as the underlying pathological process.

11. A patient diagnosed with inoperable lung cancer complains of unbearable pain. The doctor has prescribed him a painkiller. Against the background of taking this drug, the patient developed signs of intestinal obstruction. What painkiller could have caused this complication?

A. Morphine

B. Analgin (Metamizole)

C. Promedol (Trimeperidine)

D. Paracetamol

E. Fentanyl

Answer: Morphine


Morphine is a potent opioid painkiller frequently used for managing severe pain, including in patients with cancer. However, one of the potential side effects of morphine and other opioids is the development of constipation and the potential for intestinal obstruction.  

Opioid painkillers like morphine can cause several effects on the gastrointestinal system, including slowing down bowel movements (referred to as opioid-induced constipation). This effect is due to the interaction of opioids with specific receptors in the gastrointestinal tract, leading to decreased motility and increased water absorption in the intestines.  

In some cases, prolonged or high-dose use of opioids such as morphine can result in more severe complications, including intestinal obstruction. This occurs when the normal movement of intestinal contents is significantly impaired, potentially leading to abdominal pain, bloating, nausea, vomiting, and the inability to pass stool or gas.

12. Histology of an eyeball of a microslide shows a structure consisting of a chain of three neurons. The bodies of these neurons form an outer layer, an inner nuclear layer, and a ganglion layer. What structure of the eye has such a morphology?

A. Iris

B. Retina

C. Ciliary body

D. Vascular membrane

E. Sclera

Answer: Retina


The description provided in the question corresponds to the histological layers found in the retina, which is the innermost layer of the eyeball responsible for detecting light and transmitting visual information to the brain.   The retina is composed of several layers, and the three neurons mentioned in the question are organized within these layers.

From the outermost to the innermost layers, the retina consists of the following structures:   Outer layer: This layer contains photoreceptor cells, namely rods and cones, which are responsible for detecting light stimuli.   Inner nuclear layer: This layer contains various types of interneurons, including bipolar cells, horizontal cells, and amacrine cells.

These interneurons play a role in processing and transmitting visual signals.   Ganglion layer: This layer contains ganglion cells, which are the final output neurons of the retina. Ganglion cells receive signals from bipolar cells and transmit visual information through their axons, which form the optic nerve and connect to the visual centers in the brain.

13. In an experiment, a neuromuscular preparation of frog was treated with a curare-like substance. As a result, muscle contractions in response to electrical nerve stimulation disappeared. What function of the muscle cell membrane is disrupted by curare-like drugs?

A. Creation of electric potentials on both sides of the membrane

B. Maintenance of different permeability for different substances

C. Maintenance of the internal cellular structure, its cytoskeleton

D. Creating a barrier between the intracellular environment and the surrounding intercellular fluid

E. Reception of mediators in the neuromuscular synapse

Answer: Reception of mediators in the neuromuscular synapse


Curare-like substances are neuromuscular blocking agents that interfere with the normal transmission of signals from nerves to muscles at the neuromuscular junction. These substances block or inhibit the receptors for acetylcholine, a neurotransmitter responsible for transmitting signals between motor neurons and muscle cells.  

At the neuromuscular synapse, acetylcholine released from motor neurons binds to specific receptors on the muscle cell membrane, leading to the generation of an electrical signal that triggers muscle contraction. By blocking or inhibiting these receptors, curare-like drugs disrupt the reception of acetylcholine in the neuromuscular synapse.  

As a result, the muscle cell is unable to receive the neurotransmitter signal, leading to the disappearance of muscle contractions in response to electrical nerve stimulation.

14. Histology of the thyroid gland, removed during a surgery revealed destruction and atrophy of follicles and diffuse lymphocytic infiltration with formation of lymphoid follicles in the stroma. What type of thyroiditis can be characterized by these histological changes?

A. Caused by physical factors

B. Infectious and allergic

C. Viral

D. Autoimmune

E. Bacterial

Answer: Autoimmune


The histological changes described in the question, including destruction and atrophy of follicles, as well as diffuse lymphocytic infiltration with formation of lymphoid follicles in the stroma, are characteristic of an autoimmune thyroiditis called Hashimoto’s thyroiditis.  

Hashimoto’s thyroiditis is a chronic autoimmune condition where the immune system mistakenly attacks the thyroid gland. This results in inflammation and damage to the thyroid tissue. The destructive process leads to the destruction and atrophy of the thyroid follicles, which are responsible for producing and storing thyroid hormones.  

The diffuse lymphocytic infiltration with the formation of lymphoid follicles in the stroma is a hallmark of Hashimoto’s thyroiditis. Lymphocytes, a type of white blood cells, infiltrate the thyroid tissue, and the presence of lymphoid follicles indicates the presence of organized immune responses within the tissue.  

Hashimoto’s thyroiditis is the most common cause of hypothyroidism, as the destruction of the thyroid follicles impairs the production of thyroid hormones. It is considered an autoimmune condition because the immune system mistakenly targets the body’s own tissues.

15. A patient diagnosed with rheumatic myocarditis periodically experiences irregular pulse. The ECG reveals irregular occurrences of idioventricular extrasystoles. What pathogenetic mechanism causes a compensatory pause in this case?

A. Delay of excitation in atrioventricular node

B. Retrograde conduction excitation to the atria

C. Inhibition of sinus node functioning

D. Disturbed myocardial contractility

E. Myocardial refractoriness before receiving the next impulse

Answer: Myocardial refractoriness before receiving the next impulse


In the given scenario, the patient diagnosed with rheumatic myocarditis experiences irregular pulse, and the ECG reveals irregular occurrences of idioventricular extrasystoles. An extrasystole is a premature contraction originating from a site other than the sinus node, causing an abnormal heartbeat.  

During an extrasystole, the heart’s electrical conduction system is disrupted, leading to a compensatory pause. This pause occurs because the myocardium (heart muscle) needs time to recover and become refractory before it can receive the next impulse for the normal cardiac cycle.  

Refractoriness refers to the period immediately after a cardiac cell has been stimulated, during which it cannot be stimulated again. This refractory period is essential for maintaining proper coordination and rhythm of the heartbeat.

In the case of idioventricular extrasystoles, the myocardium becomes refractory before receiving the next impulse, leading to a compensatory pause and an irregular pulse.

16. A 50-ycar-old man diagnosed with chronic diffuse glomerulonephritis developed renal failure. What changes in his laboratory findings indicate impaired renal concentrating ability?

A. Hypo-and isosthenuria

B. Cylindruria

C. Hematuria

D. Hyperazotemia

E. Hypersulfatemia

Answer: Hyperazotemia


Impaired renal concentrating ability refers to the kidneys’ reduced ability to concentrate urine appropriately, resulting in decreased urine osmolality. In the context of a patient with chronic diffuse glomerulonephritis and renal failure, several laboratory findings can indicate impaired renal concentrating ability.  

Hyperazotemia refers to an elevated level of nitrogenous waste products, such as blood urea nitrogen (BUN) and creatinine, in the blood. It reflects impaired renal function but does not specifically indicate impaired renal concentrating ability.   Cylindruria refers to the presence of cylindrical structures, such as casts, in the urine.

While it can be seen in glomerulonephritis, it does not specifically indicate impaired renal concentrating ability.   Hematuria refers to the presence of blood in the urine, which can be seen in glomerulonephritis due to the inflammation and damage to the glomeruli. However, it is not directly related to impaired renal concentrating ability.  

Hypersulfatemia refers to an elevated level of sulfate in the blood. This is not typically associated with impaired renal concentrating ability.   Hypo-and isosthenuria, the correct answer, refers to the inability of the kidneys to produce concentrated urine.

In this condition, the urine osmolality is low or similar to that of plasma, indicating an impaired ability to concentrate urine. This can be observed in chronic diffuse glomerulonephritis as the disease progresses and renal function declines.

17. A 16-year-old boy came to a doctor complaining of itching between his fingers and on the abdomen, which intensifies at night. Examination of the skin revealed thin gray streaks and a fine rash. Name the causative agent of this disease:

A. Dermacentor pictus

B. Ixodes persulcatus

C. Ixodes ricinus

D. Ornitodorus papillipes

E. Sarcoptes scabiei

Answer: Sarcoptes scabiei


The symptoms described by the 16-year-old boy, including itching between his fingers and on the abdomen that intensifies at night, along with thin gray streaks and a fine rash, are indicative of scabies. Scabies is a highly contagious skin infestation caused by the mite Sarcoptes scabiei.  

Sarcoptes scabiei mites burrow into the superficial layers of the skin, where they lay eggs and cause intense itching and irritation. The burrows appear as thin gray or white lines on the skin, and the fine rash is often a result of the body’s allergic reaction to the mite and its waste products.  

The other options listed are different species of ticks and mites that are not associated with scabies. Dermacentor pictus and Ixodes persulcatus are species of ticks, Ixodes ricinus is a tick species commonly known as the castor bean tick, and Ornithodoros papillipes is a species of soft tick.

18. A patient diagnosed with chronic tuberculosis was prescribed a complex therapy. What antituberculosis medicine must be prescribed to the patient?

A. Isoniazid

B. Immunal

C. Thymalin (Thymus extract)

D. Beclometasone

E. Butadion (Phenylbutazone)

Answer: Isoniazid


Isoniazid (INH) is one of the primary and essential medications used in the treatment of tuberculosis (TB). It is considered a first-line antituberculosis drug and is commonly prescribed as part of the standard therapy for both active and latent TB infections.  

Isoniazid is a bactericidal medication that works by inhibiting the synthesis of mycolic acids, a critical component of the bacterial cell wall in Mycobacterium tuberculosis, the bacterium that causes TB. By disrupting the cell wall synthesis, isoniazid effectively kills the bacteria and helps in the eradication of the infection.  

In the treatment of chronic tuberculosis, a combination of multiple antituberculosis drugs is typically used to minimize the development of drug resistance and increase treatment effectiveness. However, among the options provided, the specific medication that is directly targeted against the Mycobacterium tuberculosis infection is isoniazid (answer choice A).  

The other options mentioned are not specific antituberculosis drugs. Immunal is not an antituberculosis medication but rather an immune system modulator.   Thymalin (Thymus extract) and Beclometasone are not used for treating tuberculosis but have different medical applications.

Butadion (Phenylbutazone) is a non-steroidal anti-inflammatory drug (NSAID) and is not effective against tuberculosis.

19. Histology of the neck of the proper gastric gland reveals small cells with high nuclear-cytoplasmic ratio and mitotic figures. What is the function of these cells?

A. Pepsinogen secretion

B. Endocrine

C. Epithelial regeneration

D. Secretion of CI- ions

E. Protective

Answer: Epithelial regeneration


The description of small cells with high nuclear-cytoplasmic ratio and mitotic figures in the histology of the neck of the proper gastric gland suggests the presence of regenerative cells.   In the gastric glands, there are different types of cells that perform various functions. The neck region of the gastric gland contains cells responsible for epithelial regeneration.

These cells have a high capacity for cell division (mitotic figures) and play a crucial role in the continuous renewal and repair of the gastric epithelium.   The gastric epithelium is constantly exposed to acidic gastric secretions and mechanical stress, which can lead to damage or loss of epithelial cells.

The regenerative cells in the neck region of the proper gastric gland serve to replace damaged or lost cells by undergoing mitotic division and generating new cells to maintain the integrity and functionality of the gastric epithelium.   The other options listed are not associated with the function of the regenerative cells in the gastric glands:   A.

Pepsinogen secretion: Pepsinogen is secreted by chief cells in the gastric glands, which are located in the base region, rather than the neck region.   B. Endocrine: Endocrine cells in the gastric glands are responsible for the secretion of hormones, such as gastrin, which regulate gastric acid secretion and other digestive processes.

However, these cells are typically found in other regions of the gastric glands.   D. Secretion of CI- ions: The secretion of chloride ions (CI-) in the stomach is primarily mediated by parietal cells, which are present in the body region of the gastric glands.   E. Protective:

The protective function of the gastric glands is primarily carried out by mucus-secreting cells, such as mucous neck cells and surface epithelial cells, which provide a protective barrier against acid and other harmful substances.

20. A 22-ycar-old patient diagnosed with acute diphtheritic myocarditis developed clinical signs of cardiogenic shock. What is the leading pathogenetic mechanism in the development of this type of shock?

A. Increased vascular tone

B. Decreased diastolic blood flow to the heart

C. Blood deposition in the veins

D. Decreased vascular tone

E. Impaired pumping function of the heart

Answer: Impaired pumping function of the heart


In the case of acute diphtheritic myocarditis, the leading pathogenetic mechanism in the development of cardiogenic shock is the impaired pumping function of the heart.   Myocarditis is an inflammatory condition that can damage the heart muscle and disrupt the normal electrical and mechanical function of the heart.

In severe cases, this can lead to heart failure and cardiogenic shock, which can be life-threatening.   The other options listed (increased vascular tone, decreased diastolic blood flow to the heart, and blood deposition in the veins) are not typically involved in the pathogenesis of cardiogenic shock.

Decreased vascular tone can occur in other types of shock, such as septic shock, but it is not the primary mechanism in cardiogenic shock.

21. A patient with endocarditis presents with a pathology of the valvular apparatus of the inner lining of the heart. What tissues form the heart valves?

A. Loose connective tissue, endothelium

B. Hyaline cartilage, endothelium

C. Cardiac muscle tissue, endothelium

D. Elastic cartilage, endothelium

E. Dense Connective tissue, endothelium

Answer: Dense Connective tissue, endothelium


The heart valves are structures that help to regulate the flow of blood through the heart by opening and closing in response to changes in pressure and flow. The heart valves are composed of dense connective tissue and endothelium.   The dense connective tissue forms the main structural component of the heart valves, providing strength and flexibility to the valve leaflets.

The connective tissue is composed of collagen, elastin, and other extracellular matrix proteins, which give the valve its characteristic properties.   The endothelium is a thin layer of specialized cells that lines the inner surface of the heart and blood vessels.

In the heart valves, the endothelial cells help to maintain the integrity and function of the valve leaflets, as well as regulate the interaction between the blood and the valve surface.   The other options listed (loose connective tissue, hyaline cartilage, cardiac muscle tissue, and elastic cartilage) are not typically present in the heart valves.

While the heart does contain cardiac muscle tissue, this tissue is not part of the valve apparatus and is instead responsible for the contraction and relaxation of the heart chambers.

22. A patient complains of increased diuresis (up to 5-7 liters of urine per 24 hours. Laboratory studies detect reduced vasopressin secretion. What cells have insufficient secretory activity in this case?

A. Neurosecretory cells of the hypothalamus

B. Endocrinocytes of the anterior pituitary

C. Pituicytes

D. Cells of the pars tuberalis

E. Endocrinocytes of the intermediate pituitary

Answer: Neurosecretory cells of the hypothalamus


In this case, the patient is experiencing increased diuresis and reduced vasopressin secretion, which suggests that the neurosecretory cells of the hypothalamus are not producing enough vasopressin. This can be caused by a variety of conditions, such as central diabetes insipidus or damage to the hypothalamus or pituitary gland.  

The other options listed (endocrinocytes of the anterior pituitary, pituicytes, cells of the pars tuberalis, and endocrinocytes of the intermediate pituitary) are not directly involved in the production or secretion of vasopressin.   The endocrinocytes of the anterior pituitary produce and secrete a variety of other hormones, such as growth hormone and thyroid-stimulating hormone.

The pituicytes are glial cells that support the function of the posterior pituitary gland.   The cells of the pars tuberalis are involved in regulating circadian rhythms and seasonal changes in hormone production. The endocrinocytes of the intermediate pituitary produce and secrete melanocyte-stimulating hormone.

23. A patient with heavy metal salt poisoning was hospitalized into the intensive care unit. What antidote should be given to the patient in this case?

A. Proserin (Neostigmine)

B. Alloxim

C. Naloxone

D. Atropine sulfate

E. Unithiol (Dimercaptopropansulfonate)

Answer: Unithiol (Dimercaptopropansulfonate)


Unithiol (Dimercaptopropansulfonate) is an antidote commonly used in cases of heavy metal salt poisoning, such as lead, mercury, and arsenic. Unithiol works by binding to the heavy metal ions in the body and forming a complex that can be excreted in the urine.  

Unithiol is a chelating agent that can effectively reduce the toxic effects of heavy metal poisoning. It is usually administered intravenously and can be given in multiple doses, depending on the severity of the poisoning. Other chelating agents, such as EDTA (ethylenediaminetetraacetic acid), may also be used in some cases of heavy metal poisoning.  

The other options listed (Proserin (Neostigmine), Alloxim, Naloxone, and Atropine sulfate) are not typically used as antidotes for heavy metal poisoning. Proserin is an acetylcholinesterase inhibitor that is used to treat myasthenia gravis and other neuromuscular disorders.  

Alloxim is a drug used in the treatment of alcohol dependence. Naloxone is an opioid antagonist used to reverse the effects of opioid overdose. Atropine sulfate is an anticholinergic drug used to treat bradycardia, intestinal hypermotility, and other conditions.

24. A man has gradually developed a plaque on the skin of his face with necrosis and an ulcer in its center. Patho histology of the biopsy material reveals proliferation of atypical epithelial cells with a large number of pathological mitoses. What disease can be characterized by these clinical and laboratory findings?

A. Papilloma

B. Fibroma

C. Skin cancer

D. Sarcoma

E. Trophic ulcer

Answer: Skin cancer


The clinical and histological findings described in the scenario are consistent with skin cancer, which is a type of malignant neoplasm that arises from the cells of the skin. The presence of a plaque with necrosis and an ulcer in the center suggests that the lesion is rapidly growing and invasive.  

The histological finding of atypical epithelial cells with a large number of pathological mitoses is a hallmark of skin cancer. Skin cancer can arise from different types of cells in the skin, including basal cells, squamous cells, and melanocytes. The most common types of skin cancer are basal cell carcinoma, squamous cell carcinoma, and melanoma.  

Papilloma and fibroma are benign tumors that can occur in the skin, but they do not typically present with the clinical and histological features described in the scenario.   Sarcoma is a type of malignant tumor that arises from connective tissue, such as bone, cartilage, or muscle, and would not be expected to have epithelial cells.

Trophic ulcers are typically caused by chronic ischemia or neuropathy, and would not present with the clinical and histological features of a rapidly growing, invasive malignancy.

25. After 10 days of treatment with an antibiotic, a patient developed gastric dyspepsia, candidiasis, jaundice, and photosensitization, which indicates that this antibiotic belongs to the following group:

A. Penicillin group

B. Rifampicin group

C. Tetracycline group

D. Aminoglycoside group

E. Cephalosporin group

Answer: Tetracycline group


The side effects described in the scenario (gastric dyspepsia, candidiasis, jaundice, and photosensitization) are commonly associated with the use of tetracycline antibiotics. Tetracyclines are a group of broad-spectrum antibiotics that are commonly used to treat bacterial infections, such as acne, respiratory tract infections, and urinary tract infections.  

Gastric dyspepsia is a common side effect of tetracyclines, as they can irritate the lining of the stomach and cause nausea, vomiting, and abdominal pain. Candidiasis, or a fungal infection caused by Candida species, can occur as a result of treatment with tetracyclines, as these antibiotics can disrupt the normal balance of microorganisms in the body.

Jaundice, or yellowing of the skin and eyes, can be a sign of liver damage, which can occur rarely with tetracycline use.   Photosensitization, or an increased sensitivity to sunlight, is another common side effect of tetracyclines, as these antibiotics can make the skin more susceptible to damage from ultraviolet radiation.  

The other options listed (penicillin group, rifampicin group, aminoglycoside group, and cephalosporin group) are not typically associated with the side effects described in the scenario. While all antibiotics can have side effects, the specific side effect profile can vary depending on the drug and the individual patient.

26. A woman diagnosed with bronchial asthma has been undergoing a glucocorticoid treatment for a long time. After an abrupt cessation of the treatment, her condition deteriorated, which manifested as a drop in blood pressure and recurrence of asthma attacks. What pathological condition can be characterized by these signs?

A. Withdrawal syndrome

B. Sensitization

C. Accumulation

D. Tachyphylaxis

Answer: Withdrawal syndrome


The signs described in the scenario (drop in blood pressure and recurrence of asthma attacks) are consistent with a withdrawal syndrome, which can occur when glucocorticoid treatment is abruptly discontinued after long-term use. Glucocorticoids are a type of corticosteroid hormone that are commonly used to treat inflammatory and autoimmune conditions, such as asthma, rheumatoid arthritis, and lupus.  

When glucocorticoid treatment is stopped abruptly, the body may experience a withdrawal syndrome, which can include symptoms such as fatigue, weakness, nausea, vomiting, low blood pressure, and recurrence of the underlying condition being treated. This is because long-term use of glucocorticoids can suppress the body’s natural production of cortisol, which can lead to a rebound effect when the drug is discontinued.  

The other options listed (sensitization, accumulation, and tachyphylaxis) are not typically associated with the signs described in the scenario. Sensitization refers to an increased response to a stimulus after repeated exposure. Accumulation refers to the buildup of a substance in the body over time.  

Tachyphylaxis refers to a rapid decrease in response to a drug after repeated doses. While these conditions can occur in some situations, they are not typically associated with glucocorticoid treatment or withdrawal.

27. A man was taking large doses of sulfonamides for a long time. Recently, he has developed significant dyspnea at rest, weakness, loss of appetite, and disturbed sleep. Laboratory blood test detects methemoglobin in his blood. What mechanism of hemoglobin inactivation in erythrocytes is observed in this patient?

A. Blockade of oxidative enzyme systems

B. Blockade of reducing enzyme systems

C. Damage of protein in hemoglobin

D. Combination of hemoglobin with sulfonamides

E. Oxidation of iron in hemoglobin

Answer: Oxidation of iron in hemoglobin


The symptoms and laboratory findings described in the scenario are consistent with methemoglobinemia, which is a condition characterized by the presence of methemoglobin in the blood.   Methemoglobin is a form of hemoglobin in which the iron ion in the heme group is oxidized from the ferrous (Fe2+) to the ferric (Fe3+) state, which impairs its ability to bind and transport oxygen.  

Sulfonamides are a class of antibiotics that can cause methemoglobinemia as a rare side effect. Sulfonamides can oxidize the iron in hemoglobin, leading to the formation of methemoglobin. This can cause symptoms such as dyspnea, weakness, and cyanosis, as well as laboratory findings of methemoglobin in the blood.  

The other options listed (blockade of oxidative enzyme systems, blockade of reducing enzyme systems, damage of protein in hemoglobin, and combination of hemoglobin with sulfonamides) are not typically associated with the mechanism of methemoglobinemia caused by sulfonamides.  

While some drugs can cause hemolytic anemia by damaging the protein in hemoglobin or by forming complexes with hemoglobin, these mechanisms are not typically associated with methemoglobinemia.

28. In the lungs, carbonic acid (H2C03) is broken down by an enzyme into water and carbon dioxide that is removed with air. What enzyme catalyzes this reaction?

A. Carbonic anhydrase

B. Cytochrome

C. Catalase

D. Peroxidase

E. Cytochrome oxidase

Answer: Carbonic anhydrase


The enzyme that catalyzes the breakdown of carbonic acid (H2CO3) into water and carbon dioxide in the lungs is carbonic anhydrase. Carbonic anhydrase is an enzyme that is found in many tissues throughout the body, including the lungs, kidneys, and digestive tract.  

In the lungs, carbonic anhydrase catalyzes the reaction between carbon dioxide and water to form carbonic acid, which then dissociates into bicarbonate ions and hydrogen ions. The hydrogen ions can then be released into the alveoli to combine with oxygen to form water, while the carbon dioxide can be exhaled.  

The other options listed (cytochrome, catalase, peroxidase, and cytochrome oxidase) are not involved in the breakdown of carbonic acid in the lungs. Cytochromes are a class of proteins that are involved in electron transport in the mitochondria.

Catalase and peroxidase are enzymes that are involved in the breakdown of hydrogen peroxide in the body. Cytochrome oxidase is an enzyme that is involved in the electron transport chain in the mitochondria.

29. What part of the nervous system nervous system is under influence of thyroid hormones?

A. Sympathetic division of autonomic nervous system

B. Metasympathetic division of autonomic nervous system

C. Parasympathetic division autonomic nervous system

D. Somatic nervous system

E.Parasympathetic and Metasympathetic division of autonomic nervous system

Answer: Sympathetic division of autonomic nervous system


The sympathetic division of the autonomic nervous system is under the influence of thyroid hormones. The autonomic nervous system is a part of the peripheral nervous system that regulates involuntary functions such as heart rate, blood pressure, and respiratory rate.  

The autonomic nervous system is divided into two main branches: the sympathetic division and the parasympathetic division.   Thyroid hormones play a key role in regulating the sympathetic division of the autonomic nervous system. Thyroid hormones increase the sensitivity of the sympathetic nervous system to neurotransmitters such as norepinephrine, which can increase heart rate, blood pressure, and metabolic rate.  

Thyroid hormones can also affect other functions that are regulated by the sympathetic nervous system, such as thermoregulation and gastrointestinal motility.   The other options listed (metasympathetic division of autonomic nervous system, parasympathetic division of autonomic nervous system, and somatic nervous system) are not typically under the influence of thyroid hormones.  

The metasympathetic division is not a recognized division of the autonomic nervous system. The parasympathetic division is regulated by a different set of neurotransmitters and hormones, such as acetylcholine. The somatic nervous system is responsible for voluntary muscle movements and is not regulated by the autonomic nervous system.

30. A patient with hereditary hyperammonemia, caused by disturbed ornithine cycle, developed secondary orotaciduria. What metabolite of the ornithine cycle has high levels in this case, causing the increased synthesis of orotic acid?

A. Urea

B. Ornithine

C. Citrulline

D. Carbamoyl phosphate

E. Argininosuccinate

Answer: Carbamoyl phosphate


In hereditary hyperammonemia caused by a disturbance in the ornithine cycle, the metabolite that is elevated is carbamoyl phosphate. The ornithine cycle is a metabolic pathway that takes place in the liver and helps to convert toxic ammonia into urea, which can be excreted in the urine.  

In hereditary hyperammonemia, there is a defect in one of the enzymes involved in the ornithine cycle, which leads to an accumulation of ammonia in the blood. This can cause a variety of symptoms, including neurological problems and liver damage.  

One of the byproducts of the ornithine cycle is orotic acid, which is normally excreted in the urine. In hereditary hyperammonemia, however, the accumulation of carbamoyl phosphate can lead to an increase in the synthesis of orotic acid, which can then be excreted in the urine.

This leads to the secondary orotic aciduria that is seen in these patients.   The other options listed (urea, ornithine, citrulline, and argininosuccinate) are all metabolites that are involved in the ornithine cycle, but they are not the metabolite that is elevated in hereditary hyperammonemia and responsible for the increased synthesis of orotic acid.

31. Cellular cytoplasm has high levels of aminoacyl-tRNA synthetase enzyme. What process in the cell is provided by this enzyme?

A. Transcription

B. Replication

C. Elongation

D. Amino acid activation

E. Repair

Answer: Amino acid activation


Aminoacyl-tRNA synthetase is an enzyme that plays a critical role in protein synthesis by activating amino acids and attaching them to tRNA molecules. This process is called amino acid activation, and it is the first step in the process of translation, which is the synthesis of proteins from mRNA templates.  

During amino acid activation, the amino acid is first activated by the addition of ATP, forming an aminoacyl-AMP intermediate. The aminoacyl-tRNA synthetase enzyme then catalyzes the transfer of the activated amino acid from the aminoacyl-AMP intermediate to the appropriate tRNA molecule, forming an aminoacyl-tRNA complex.  

This complex can then be used by the ribosome to add the amino acid to the growing polypeptide chain during the process of elongation.   The other options listed (transcription, replication, elongation, and repair) are not typically provided by aminoacyl-tRNA synthetase.  

Transcription is the process of synthesizing RNA from a DNA template. Replication is the process of copying DNA molecules to produce new cells. Elongation, as mentioned above, is a process in protein synthesis. Repair refers to the process of restoring damaged DNA to its original state.

32. When installing an intrauterine contraceptive, the doctor violated the rules of asepsis, and the uterine cavity was contaminated with an infection. What uterine membrane will most likely become inflamed in this woman?

A. Endometrium

B. Parametrium

C. Perimetrium

D. Myometrium

Answer: Endometrium


Infections that occur after intrauterine contraceptive (IUC) placement are often related to contamination of the uterine cavity during the procedure. The most likely uterine membrane to become inflamed in this scenario is the endometrium.   The endometrium is the innermost layer of the uterus and is the site of implantation of a fertilized egg during pregnancy.

It is also the layer of the uterus that is shed during menstruation. Infections of the endometrium are known as endometritis and can occur as a result of contamination during procedures such as IUC placement, childbirth, or miscarriage.  

The other options listed (parametrium, perimetrium, and myometrium) are not typically affected by infections related to IUC placement. The parametrium is the connective tissue that surrounds the uterus and contains blood vessels and nerves.   The perimetrium is the outermost layer of the uterus, consisting of a thin layer of connective tissue and mesothelium.

The myometrium is the middle layer of the uterus, consisting of smooth muscle tissue that contracts during labor and delivery.   While these layers may be affected by other conditions, they are not typically involved in infections related to IUC placement.

33. When testing donors at a blood transfusion station, antibodies to human immunodeficiency virus were detected in the serum of one of the donors. What method is recommended to confirm the diagnosis of HIV infection?

A. Electron microscopy

B. Enzyme-linked immunosorbent assay

C. Western blotting (immunoblotting)

D. Radioimmunoassay

E. Immunofluorescence

Answer: Western blotting (immunoblotting)


Western blotting is a laboratory technique that is used to detect specific proteins in a sample, such as HIV proteins in the serum of an infected person. The technique involves separating the proteins in the sample using gel electrophoresis, transferring them onto a membrane, and then probing the membrane with antibodies that are specific to the proteins of interest.

This can confirm the presence of HIV-specific antibodies in the serum and can help to diagnose HIV infection.   The other options listed (electron microscopy, enzyme-linked immunosorbent assay, radioimmunoassay, and immunofluorescence) are not typically used to confirm the diagnosis of HIV infection.  

Electron microscopy is a technique that can be used to visualize the structure of viruses, but it is not typically used for HIV diagnosis. Enzyme-linked immunosorbent assay (ELISA), radioimmunoassay, and immunofluorescence are all used as screening tests for HIV antibodies, but they are not typically used for confirmation because they can produce false-positive results.

34. Autopsy of the body of a 40-year- old man revealed enlarged group follicles in the small intestine Their surface has furrows and convolutions, arranged in a pattern similar to that of a brain cortex. The follicles protrude from under the intestinal mucosa and are gray-red on section. Microscopy shows proliferation of monocytes, histiocytes, reticular cells, clusters of macrophages that form granulomas, displaced lymphocytes. What infectious disease can be characterized by these changes?

A. Typhoid fever

B. Amoebiasis

C. Dysentery

D. Typhus

E. Cholera

Answer: Typhoid fever


The description of the enlarged group follicles with furrows and convolutions arranged in a pattern similar to that of a brain cortex, along with the presence of granulomas, displaced lymphocytes, and clusters of macrophages, are characteristic of a condition known as intestinal tuberculosis.  

Intestinal tuberculosis is a form of extrapulmonary tuberculosis that affects the gastrointestinal tract, particularly the ileocecal region of the small intestine. The disease is caused by the bacterium Mycobacterium tuberculosis, which can spread to the intestines through the bloodstream or by ingestion of contaminated food or water.  

The enlarged follicles with furrows and convolutions, known as “cobblestone” appearance, are a classic finding in intestinal tuberculosis and are the result of a chronic inflammatory process that leads to the formation of granulomas. These granulomas are composed of clusters of macrophages, histiocytes, and lymphocytes, and can be seen on microscopy.  

The other options listed (amoebiasis, dysentery, typhus, and cholera) are not typically associated with the specific histological findings described in this scenario. Amoebiasis is caused by the protozoan parasite Entamoeba histolytica and can cause colitis and ulcers in the intestines.  

Dysentery is a condition characterized by inflammation of the intestines, often caused by bacterial infections such as Shigella or Salmonella. Typhus is a bacterial infection that can cause fever, rash, and other symptoms. Cholera is a bacterial infection that can cause severe diarrhea and dehydration.

35. After a tibial fracture, the patient presents with excessive bone tissue production (exostosis). What type of regeneration is observed in this case?

A. Pathological insufficient

B. Physiological

C. Pathologically excessive

D. Reparative

Answer: Pathologically excessive


Regeneration is the process by which damaged tissues or organs are replaced with newly generated tissue. There are two main types of regeneration: physiological and reparative. Physiological regeneration refers to the normal, ongoing processes of tissue turnover and repair that occur in the body.  

Reparative regeneration, on the other hand, refers to the process of tissue repair and replacement that occurs in response to injury or disease.   In the case of the tibial fracture, the excessive bone tissue production (exostosis) is an abnormal response to the injury and represents pathologically excessive regeneration.

This excessive tissue growth can be problematic and may cause pain, restricted movement, or other complications.   The other options listed (pathological insufficient and reparative) do not accurately describe the type of regeneration that is observed in this case.

Pathological insufficient regeneration refers to a situation where the body is unable to regenerate tissue adequately, leading to chronic wounds or non-healing injuries.   Reparative regeneration, as mentioned above, refers to the process of tissue repair and replacement that occurs in response to injury or disease.

36. After bacteria enters the body, the first stage of immune response formation occurs. What is the role of macrophages in this process?

A. Processing and presentation of antigen to T killers

B. Activation of T killers

C. Production of immunoglobulins

D. Processing and presentation of antigen to T helpers

E. Activation of NK cells

Answer: Processing and presentation of antigen to T helpers


When bacteria enter the body, they are taken up by macrophages, which are specialized cells of the immune system that phagocytose (engulf) foreign particles and pathogens. Once inside the macrophage, the bacteria are broken down into small fragments, or antigens, which are then displayed on the surface of the macrophage together with major histocompatibility complex (MHC) molecules.  

These MHC-antigen complexes are recognized by T helper cells, which are a type of white blood cell that play a critical role in coordinating the immune response. The binding of the T helper cell to the macrophage activates the T helper cell, which then secretes cytokines that activate other immune cells, such as B cells and T killer cells.  

The other options listed (activation of T killers, production of immunoglobulins, activation of NK cells) are not typically the primary role of macrophages in the early stages of the immune response to bacteria.  

T killer cells and NK cells are involved in directly killing infected cells, while B cells are involved in producing antibodies (immunoglobulins) against bacteria. However, macrophages do play a role in activating these other cells through the production of cytokines and other signaling molecules.

37. Researchers that study physiology of the heart has determined that excessive atrial distension causes a decrease in sodium reabsorption in the distal convoluted tubule and increases glomerular filtration rate. What substance is the most likely cause of the physiological changes detected by the researchers ?

A. Natriuretic hormone

B. Aldosterone

C. Renin

D. Vasopressin

E. Angiotensin

Answer: Natriuretic hormone


The physiological changes detected by the researchers, including a decrease in sodium reabsorption in the distal convoluted tubule and an increase in glomerular filtration rate in response to excessive atrial distension, are characteristic of the actions of natriuretic hormones.  

Natriuretic hormones are a family of peptides that are secreted by the heart in response to increased atrial distension, which can occur in conditions such as heart failure or hypertension. These hormones act on the kidneys to increase sodium and water excretion, leading to a decrease in blood volume and blood pressure.  

One of the main actions of natriuretic hormones is to inhibit the reabsorption of sodium in the distal convoluted tubule of the kidney, which leads to an increase in the excretion of sodium and water. This effect is opposite to the actions of aldosterone, which promotes sodium reabsorption and water retention.  

The other options listed (aldosterone, renin, vasopressin, and angiotensin) are all involved in the regulation of fluid and electrolyte balance, but they do not typically cause the physiological changes described in this scenario.  

Aldosterone promotes sodium reabsorption and water retention, while renin, vasopressin, and angiotensin are involved in regulating blood pressure and fluid balance through a complex system known as the renin-angiotensin-aldosterone system (RAAS).

38. Total energy metabolism of a person can be calculated, if the following value is known:

A. Lipid intake

B. Carbohydrate intake

C. 02 intake

D. CO2 release

E. Protein intake

Answer: 02 intake


When the body metabolizes food to produce energy, oxygen is consumed and carbon dioxide (CO2) is produced. The ratio of O2 consumption to CO2 production can be used to estimate the total energy expenditure of the body. The equation for calculating energy expenditure is as follows:  

Energy expenditure = VO2 x (caloric equivalent of O2)   where VO2 is the rate of oxygen consumption and the caloric equivalent of O2 is a constant that represents the amount of energy produced per unit of oxygen consumed.   The other options listed (lipid intake, carbohydrate intake, CO2 release, and protein intake) are not directly related to the calculation of energy metabolism.

While the intake of lipids, carbohydrates, and proteins can provide information about the types of nutrients that are being metabolized, they do not provide a direct measure of energy metabolism.  

CO2 release is related to energy metabolism, but it cannot be used alone to calculate energy expenditure because the amount of CO2 produced also depends on other factors such as respiratory rate and tissue metabolism.

39. A young man came to a doctor with complaints of pain in his heart. It turns out that he drinks up to 8 cups of coffee per day. What is the effect of the caffeine contained in coffee on the human heart?

A. Decreases the force of heart contractions

B. Increases body temperature

C. Slows down conduction in the heart

D. Causes tachycardia, Increases myocardial oxygen demand

E. Causes narrowing of coronary vessels

Answer: Causes tachycardia, Increases myocardial oxygen demand


Caffeine is a stimulant that acts on the central nervous system to increase alertness and reduce fatigue. It does this by blocking the action of adenosine, a neurotransmitter that promotes sleep and suppresses arousal. In addition to its effects on the brain, caffeine also has several effects on the cardiovascular system.  

One of the main effects of caffeine on the heart is to increase heart rate, or cause tachycardia. This is due to its ability to stimulate the sympathetic nervous system, which is responsible for the “fight or flight” response. When the sympathetic nervous system is activated, it increases heart rate and contractility, which can cause an increase in myocardial oxygen demand.  

The other options listed (decreases the force of heart contractions, increases body temperature, slows down conduction in the heart, causes narrowing of coronary vessels) are not typically associated with the effects of caffeine on the human heart.  

While caffeine can have other effects on the body, such as increasing body temperature or causing vasoconstriction, its effects on the heart are primarily related to its ability to stimulate the sympathetic nervous system and increase heart rate.

40. A 37-year-old man was hospitalized into the STD department with the diagnosis of syphilis. What medicine will be used for his treatment?

A. Biseptol (Co-trimoxazole)

B. Benzylpenicillin

C. Levomycetin (Chloramphenicol)

D. Tetracycline

E. Nitroxoline

Answer: Benzylpenicillin


Syphilis is a sexually transmitted disease caused by the bacterium Treponema pallidum. Penicillin is the recommended treatment for all stages of syphilis, including primary, secondary, and early latent syphilis.  

In general, syphilis is treated with a single injection of benzylpenicillin, although the exact treatment regimen may vary depending on the stage and severity of the infection.   The other options listed (Biseptol, Levomycetin, Tetracycline, Nitroxoline) are not typically used for the treatment of syphilis.

Biseptol (Co-trimoxazole) is a combination of sulfamethoxazole and trimethoprim, which is used to treat bacterial infections such as urinary tract infections and respiratory infections.   Levomycetin (Chloramphenicol) is an antibiotic that is used to treat a variety of bacterial infections, but it is not typically used for the treatment of syphilis.

Tetracycline and Nitroxoline are also antibiotics that have a broad spectrum of activity against different bacteria, but they are not considered first-line treatments for syphilis.

41.  A person diagnosed with pneumoconiosis and respiratory failure was hospitalized . What component of external respiration is typically affected in this pathology?

A. Decreased pulmonary ventilation

B. Decreased gas diffusion

C. Disturbed nervous regulation of external respiration

D. Disturbed humoral regulation of external respiration

E. Disturbed pulmonary perfusion

Answer: Decreased gas diffusion


One of the main components of external respiration that is affected in pneumoconiosis is gas diffusion. Gas exchange occurs across the alveolar-capillary membrane in the lungs, where oxygen diffuses from the air into the blood and carbon dioxide diffuses from the blood into the air.  

In pneumoconiosis, the lung tissue becomes thickened and scarred, which can impair the diffusion of gases across the alveolar-capillary membrane. This can lead to a decrease in oxygen uptake and an increase in carbon dioxide retention, which can contribute to respiratory failure.  

The other options listed (decreased pulmonary ventilation, disturbed nervous regulation of external respiration, disturbed humoral regulation of external respiration, disturbed pulmonary perfusion) can also contribute to respiratory failure in some cases, but they are not typically the primary component of external respiration that is affected in pneumoconiosis.  

Decreased pulmonary ventilation, for example, can impair the movement of air into and out of the lungs, while disturbances in nervous or humoral regulation can affect the control of breathing. Disturbed pulmonary perfusion can also impair gas exchange by reducing blood flow to the lungs, but this is less commonly a feature of pneumoconiosis.

42. A man suffers from progressive muscular dystrophy. What indicator of urinary nitrogen metabolism characterizes this condition?

A. Creatinine

B. Uric acid

C. Urea

D. Creatine

E. Ammonium salts

Answer: Creatine


In the context of progressive muscular dystrophy, the indicator of urinary nitrogen metabolism that characterizes this condition is creatine.   Progressive muscular dystrophy refers to a group of genetic disorders that result in progressive degeneration and weakness of the skeletal muscles. These conditions are characterized by the loss of muscle tissue over time.  

Creatine is a nitrogenous compound that plays a crucial role in energy metabolism within muscle cells. It is synthesized from the amino acids arginine, glycine, and methionine primarily in the liver and kidneys, and then transported to the muscles. In the muscles, creatine is converted into phosphocreatine, which serves as an energy reserve and helps provide quick bursts of energy during muscle contraction.  

In individuals with progressive muscular dystrophy, the muscle tissue is progressively lost, leading to decreased muscle mass and function. As a result, there is a reduction in the amount of creatine available in the muscles.   This reduction in muscle creatine levels can subsequently affect urinary nitrogen metabolism, leading to a decrease in the excretion of creatine in the urine.  

The other options listed are not specifically related to the indicator of urinary nitrogen metabolism in progressive muscular dystrophy:   A. Creatinine: Creatinine is a waste product of muscle metabolism that is excreted in the urine. While creatinine levels may be affected by muscle mass, it is not the primary indicator characterizing progressive muscular dystrophy.  

B. Uric acid: Uric acid is a byproduct of purine metabolism and is not directly related to muscular dystrophy.   C. Urea: Urea is a waste product formed in the liver as a result of protein breakdown. While it is an indicator of nitrogen metabolism, it is not specific to progressive muscular dystrophy.  

E. Ammonium salts: Ammonium salts are produced as part of nitrogen metabolism and are excreted primarily in the urine. While they are involved in nitrogen metabolism, they are not specific to progressive muscular dystrophy.

43. A 45-year-old woman was diagnosed with parathyroid insufficiency. How will the functioning of the kidneys change with this pathology?

A. Vitamin B6 synthesis will decrease

B. Prostaglandin synthesis will increase

C. Calcium filtration in the glomeruli will decrease

D. Calcium reabsorption in the distal tubules will decrease

E. Urokinase synthesis will increase

Answer: Calcium reabsorption in the distal tubules will decrease


In the case of parathyroid insufficiency, there is a deficiency or dysfunction of the parathyroid hormone (PTH), which is responsible for regulating calcium and phosphate levels in the body. PTH plays a crucial role in maintaining calcium homeostasis.   One of the main actions of PTH is to increase calcium reabsorption in the distal tubules of the kidneys.

By promoting the reabsorption of calcium, PTH helps to regulate blood calcium levels and prevent excessive calcium loss through urine.   In the absence or insufficiency of PTH, as in the case of parathyroid insufficiency, the functioning of the kidneys is affected. Without adequate PTH levels, there is a decrease in the reabsorption of calcium in the distal tubules of the kidneys.

This leads to increased excretion of calcium in the urine and reduced calcium retention in the body.   The other options provided are not directly associated with the changes in kidney functioning in parathyroid insufficiency:   A. Vitamin B6 synthesis will decrease: Vitamin B6 synthesis is not directly related to parathyroid hormone or parathyroid insufficiency.  

B. Prostaglandin synthesis will increase: Prostaglandin synthesis is not directly affected by parathyroid hormone or parathyroid insufficiency.   C. Calcium filtration in the glomeruli will decrease: The filtration of calcium in the glomeruli is not primarily regulated by parathyroid hormone.

The primary role of PTH is in the reabsorption of calcium in the renal tubules.   E. Urokinase synthesis will increase: Urokinase is an enzyme involved in fibrinolysis and is not directly related to parathyroid hormone or parathyroid insufficiency.

44. Ammonia is extremely toxic to human CNS. What is the main way of its neutralization in the nervous tissues?

A. Urea synthesis

B. Ammonium salt synthesis

C. Transamination

D. Formation of paired compounds

E. Glutamine synthesis

Answer: Glutamine synthesis


Ammonia is a highly toxic substance, particularly to the central nervous system (CNS). In order to prevent the accumulation of toxic levels of ammonia in nervous tissues, the body utilizes various mechanisms for its neutralization.   One of the main ways in which ammonia is neutralized in the nervous tissues is through the process of glutamine synthesis.

Glutamine is an amino acid that is synthesized in a reaction involving the enzyme glutamine synthetase. In this reaction, ammonia is combined with glutamate to form glutamine.   Glutamine serves as a carrier of ammonia in the body, allowing for its safe transport and elimination from the CNS.

Glutamine can be transported across cell membranes and taken up by other tissues, such as the liver, where it can undergo further metabolism to ultimately eliminate the ammonia from the body.   The other options provided are not the main ways of neutralizing ammonia in the nervous tissues:  

A. Urea synthesis: Urea synthesis primarily occurs in the liver and is the main pathway for ammonia detoxification in the body as a whole, but it is not the main way of neutralizing ammonia specifically in the nervous tissues.  

B. Ammonium salt synthesis: The formation of ammonium salts does not directly neutralize ammonia in the nervous tissues.   C. Transamination: Transamination refers to the transfer of an amino group from one molecule to another and is not a primary mechanism for ammonia neutralization in the nervous tissues.  

D. Formation of paired compounds: The formation of paired compounds does not specifically neutralize ammonia in the nervous tissues.

45. For the last three days a woman has been suffering from profuse diarrhea. Her blood gas test shows reduced levels of HC03. What is the leading mechanism in compensation of acid- base imbalance in this patient?

A. Decreased Reabsorption of bicarbonate in the kidneys

B. Increased pulmonary ventilation

C. Decreased ammonia excretion with urine

D. Decreased pulmonary ventilation

Answer: Increased pulmonary ventilation


In the case of profuse diarrhea, the loss of fluid from the body can lead to a decrease in bicarbonate ions (HCO3-) in the blood, resulting in an acid-base imbalance known as metabolic acidosis. This occurs because bicarbonate ions are lost along with the excess fluid in diarrhea.  

To compensate for this acid-base imbalance, the body initiates certain mechanisms to restore the balance. One of the primary compensatory mechanisms for metabolic acidosis is an increase in pulmonary ventilation, which refers to the rate and depth of breathing.   Increased pulmonary ventilation helps to decrease the levels of carbon dioxide (CO2) in the blood.

This occurs through the elimination of CO2 from the body during exhalation. By reducing the CO2 levels in the blood, the body can shift the balance towards a more alkaline state and help compensate for the loss of bicarbonate ions.   The other options provided are not the leading mechanisms of compensation for acid-base imbalance in this patient:  

A. Decreased reabsorption of bicarbonate in the kidneys: While reduced reabsorption of bicarbonate in the kidneys can contribute to metabolic acidosis, it is not the leading mechanism of compensation in this case.   C. Decreased ammonia excretion with urine: Ammonia excretion is not directly involved in compensating for acid-base imbalance in this scenario.  

D. Decreased pulmonary ventilation: Decreased pulmonary ventilation would not be a compensatory mechanism for metabolic acidosis. It would further exacerbate the acid-base imbalance.

46. Formation of a large number of immunoglobulins with different antigenic specificity occurs from a small number of genes. What process makes this possible?

A. Transcription

B. Translocation

C. Deletion

D. Gene recombination

E. Replication

Answer: Gene recombination


During the development of B cells, the genes that encode the variable regions of the heavy and light chains of immunoglobulins undergo somatic recombination, a process that involves the rearrangement of gene segments to generate a diverse repertoire of antigen receptors.  

This process involves the rearrangement of gene segments, including variable (V), diversity (D), and joining (J) gene segments, through a series of DNA cleavage and rejoining events. The specific combination of V, D, and J gene segments that are brought together determines the specificity of the antigen receptor.  

Thus, gene recombination allows for a diverse range of immunoglobulins to be generated from a limited number of genes, allowing the immune system to recognize and respond to a wide variety of antigens.

47. A woman with low blood pressure was parenterally administered a hormone, after which she developed an increase in blood pressure and increased levels of glucose and lipids in her blood . What hormone did she receive?

A. Insulin

B. Adrenaline

C. Glucagon

D. Progesterone

E. Thyroxine

Answer: Adrenaline


The hormone that the woman received that caused an increase in blood pressure, as well as increased levels of glucose and lipids in her blood, is adrenaline. Adrenaline, also known as epinephrine, is a hormone that is released from the adrenal glands in response to stress or other stimuli.  

Adrenaline acts on various organs and tissues in the body to produce a range of physiological responses, including an increase in heart rate and blood pressure, as well as an increase in the breakdown of glycogen (a storage form of glucose) and the release of fatty acids from adipose tissue.

These effects help to prepare the body for a “fight or flight” response to stress, by increasing the availability of energy and oxygen to the muscles.  

Parenteral administration of adrenaline can cause a rapid and potent elevation of blood pressure, along with an increase in blood glucose and lipid levels, as described in the scenario provided.

48. Autopsy of the body of a person, who died after an abdominal surgery, revealed numerous thrombi in the veins of lesser pelvis. Clinical diagnosis of thromboembolic syndrome was made . Where in the body will the thromboembolic be found in this case?

A. Portal vein

B. Left ventricle of the heart

C. Brain

D. Leg veins

E. Pulmonary arteries

Answer: Pulmonary arteries


Thromboembolic syndrome is a condition where blood clots (thrombi) form in the blood vessels of the body and can potentially travel to other parts of the body, causing an obstruction of blood flow.  

In the scenario provided, the autopsy revealed numerous thrombi in the veins of the lesser pelvis, which suggests that the patient had deep vein thrombosis (DVT), a condition where blood clots form in the deep veins of the legs or pelvis.  

If these clots break off and travel through the bloodstream, they can potentially lodge in the pulmonary arteries, which carry blood from the heart to the lungs. This can cause a pulmonary embolism, a serious and potentially life-threatening complication.

49. The patient has lost tactile and thermal sensitivity because of a head injury. What gyrus was damaged in the brain in this case?

A. Postcentral gyrus

B. Cingulate gyrus

C. Precentral gyrus

D. Angular gyrus

E. Supramarginal gyrus

Answer: Postcentral gyrus


The postcentral gyrus is located in the parietal lobe of the brain, and it is involved in the processing and perception of somatosensory information, including touch, temperature, and pain sensation.   Damage to the postcentral gyrus can result in a loss of sensation in the body parts that are represented in that area of the brain.

For example, damage to the postcentral gyrus in the parietal lobe of the brain that corresponds to the hand could result in a loss of tactile sensation and temperature perception in the hand.  

Therefore, in this case, the loss of tactile and thermal sensitivity suggests that the postcentral gyrus corresponding to the affected body part has been damaged as a result of the head injury.

50. A patient has developed severe muscle weakness as a result of combined digitoxin and furosemide therapy for chronic heart failure . What electrolyte imbalance will be observed in the patient’s blood in this case?

A. Hypochloremia

B. Hypercalcemia

C. Hypocalcemia

D. Hyperkalemia

E. Hypokalemia

Answer: Hypokalemia


Digitoxin is a cardiac glycoside used for the treatment of heart failure, and it works by increasing the force of contraction of the heart muscle. However, it can also increase the risk of hypokalemia, which is a condition characterized by low levels of potassium in the blood.  

Furosemide is a loop diuretic used to treat edema (fluid retention) associated with heart failure and other conditions. It works by increasing the excretion of sodium and water from the body, but it can also lead to potassium loss in the urine, further exacerbating the risk of hypokalemia.  

Hypokalemia can cause a range of symptoms, including muscle weakness, cramping, and fatigue. Severe hypokalemia can also lead to more serious complications, such as cardiac arrhythmias and respiratory failure.

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