1. What is the name of the intracellular molecule that transmits signals from receptors on the cell surface to target molecules inside the cell?
n Answer:Second messenger
2. rRNA contained in the large 50s subunit works as an enzyme for making peptide bond. What is the name of RNA that is capable of catalyzing specific biochemical reactions?
n Answer:ribozyme
3. Oxidative phosphorylation is driven by an electrochemical gradient generated by what system?
n Answer:Electron transport system
4. Flavin mononucleotide(FMN) and Flavin adenine dinucleotide(FAD) play important roles as coenzyme. Which vitamin is necessary for activation of these enzymes?
n Answer:Vitamin B2
5. Production of Aminolevulinic acid (ALA) is the rate determining step of porphyrin synthesis. What is the co-enzyme that catalyze this step?
n Answer:Vitamin B6
6. What is the glycoprotein coded in D area of chromosome Ⅵ and exists in surface of antigen-presenting cells?
n Answer:MHC class Ⅱ molecule
n Comment:
MHC class Ⅰ and Ⅱ are coded in chromosome Ⅵ. But β2-microglobulin, subunit of MHC class Ⅱ, is corded in chromosome XV
7. What is the class of immunoglobulin which appears in the blood of patients with Henoch-Schonlein purpura?
n Answer:IgA
8. We cannot determine whether the neonate born from a HIV positive mother is infected with HIV or not through antibody test after birth. What is the substance in fetal blood which causes this problem?
n Answer:Transferring antibody / IgG
n Comment:
It is not effective to determine whether neonate up to 18 months old is infected with HIV through antibody test. Detecting HIV-RNA is recommended.
9. What is the substance which reduces energy production through glycolysis in skeletal muscle during exercise?
n Answer:Proton(H+) / Lactic acid
n Comment:The slowest rate-limiting-enzyme of glycolysis is PFK-1 and proton is inhibitor of this enzyme.
10. After the removal of parathyroid adenoma, osteogenesis accelerates according to Hungry-bone syndrome. What electrolyte decreases in blood concentration through this phenomenon?
n Answer:Calcium
11. What is the corrected QT interval when heart rate is 60/min and QT interval is 0.40 seconds?
n Answer:0.40 seconds (400ms)
n Comment:Bazett’s Formula; → = 0.40
12. If patients with Basedow’s disease eat a large amount of carbohydrate, they may develop periodic paralysis in the next morning. What peptide hormone causes this symptom?
n Answer:Insulin
13. What is this arrhythmia? 【Picture is deleted】
n Answer:Ventricular premature contraction
14. What is the anterior pituitary hormone which promotes proliferation and differentiation of the epiphyseal cartilage?
n Answer:Growth hormone(GH)
15. What is the substance which is created by cutting of pro-insulin in the pancreatic β cell and is useful to know the rate of insulin secretion?
n Answer:C peptide
16. Which ABO blood type would not appear in children when both of their parents have blood type AB?
n Answer:Blood type O
n Comment:The infant with blood type AB(50%) and A(25%) and B(25%) can be born.
17. There is a repeated sequence of TTAGGG in the end of DNA and this is essential to replicate DNA. What is the name of this structure?
n Answer:Telomere
n Comment:Telomere is elongated by telomerase. Although tumor cell, stem cell and genital cell has high active telomerase, the other cells don’t.
18. In case of infant BLS with 3 medical staffs, how many times of chest compression should be given in one cycle?
n Answer:15
n Comment:In the case of infant, the most frequent cause of cardiopulmonary arrest is hypoxemia.Therefore, artificial respiration is important. If there is only one staff, the ratio of chest compression and artificial respiration is 30:2, but if there are more than 2 staffs, the ratio changes to 15:2. This ratio can convert 15:2 into 30:4, which indicates the importance of blood oxygenation.
19. What is the main hematopoietic organ in fetus at 32 weeks of pregnancy?
n Answer:Bone marrow
20. What is the substance which doesn’t show immunogenicity in itself but works by combining with some protein in the body?
n Answer:Hapten
21. What forms cytoskeleton of cilium?
n Answer:Tubulin
22. In case of oral administration, a part of drugs is metabolized in the liver before they are distributed to the systemic tissue. What is this phenomenon called?
n Answer:First pass effect
n Comment:Sublingual and intravenous administration can prevent first pass effect so bioavailability is 100%.
23. What is the lesion in the patients with right-handed with cerebral infarction who can only draw 12 o’clock to 7 but not from 8 to 11 when drawing a picture of clock?
n Answer:Right parietal association area
24. What is the DNA which is made by reverse transcription of mRNA after splicing?
n Answer:complementary DNA (cDNA)
25. Which antibody is detected in the patients with rheumatoid arthritis and has low sensitivity and high specificity?
n Answer:anti-CCP antibody (anti-cyclic citrullinated peptide antibody)
26. Lipopolysaccharides(LPS) of gram-negative rods(GNR) activate a certain enzyme. What substance is produced by this enzyme and causes fever?
n Answer:Prostaglandin
27. What is the substance produced by the metabolism in skeletal muscle and uses the measurement of GFR?
n Answer:Creatinine
n Comment:In the nephron, creatinine is only excreted by glomerular filtration and hardly secreted and reabsorbed through seminiferous tubule so creatinine clearance is used as an easy and alternative substance of inulin.
28. What is the theoretical volume that would be necessary to contain the total amount of an administrated drug at the same concentration that is observed in the blood plasma and represents the degree to which a drug is distributed in body tissue?
n Answer:Volume of distribution
n Comment:Substances that have higher protein binding ratio have lower VD, whereas lower protein binding ratio have higher VD. Substances with higher VD tend to be excreted from the body slowly.
29. A 61-year-old man complains numbness and spasm of his hands and legs. He has had acholic stool for the past four weeks. The serum studies showed that his anti-mitochondrial antibody was positive. What is the mechanism for the symptoms?
n Answer:Hypocalcemia
30. Blood plasma has a higher concentration of anions than that of the interstitial space. This is due to the presence of anionic proteins. What is this effect called?
n Answer:Donnan Effect / Donnan equilibrium
31. What is the metabolic pathway directly inhibited by a cyanide?
n Answer:Electron-transport-chain(system)
32. Niacin is synthesized in the body from which amino acid?
n Answer:tryptophan
33. Helper T cell activates through stimulation not only from MHC class Ⅱ but also support signal(stimulation). What is this phenomenon called?
n Answer:Anergy
n Comment:Support signal is established with CD86 of dendritic cell and CD28 of helper T cell.
34. Unlike the neural fibers in the central nervous system, injured peripheral nerves regenerate completely if adequately treated. What is the name of a physiological finding which is considered as a visible evidence for recovery of nerves?
n Answer:Tinel’s sign
n Comment:Tinel’s sign is performed by tapping over the injured nerve to elicit a sensation of tingling or pain in the distribution of nerve. As the injured nerves regenerate, the injured part of the nerves shortens, thereby the tingling provoked by tapping moves peripherally. This is an important sign commonly seen when nerve regeneration occurs.
35. Mitochondria conducts aerobic metabolism and is injured by oxidative stress. What is the mechanism through which degrades mitochondria in injured cell?
n Answer:Mitophagy / Autophagy
36. What metabolic factor contributes the most to the regulation of cerebral circulation?
n Answer:carbon dioxide
37. A-7-year-old woman, had total thyroidectomy yesterday. She is suffering from numbness of the lip and stiffness of the finger. What ion does she need to be injected?
n Answer:Calcium
n Comment:Hypernatremia rarely occurs since we have double protection system, the sense of thirst and secretion of ADH. In which structure is the centre of this protection system exist?
38. What kind of the arrhythmia is shown in the figure below? 【Picture is deleted】
n Answer:Atrial Fibrillation
39. In the patients with chronic granulomatous disease(CGD), staphylococcus aureus cannot be disinfected but Streptococcus pneumoniae can be disinfected. Name the enzyme which causes this phenomenon.
n Answer:Catalase
40. What is the second messenger produced by the stimulation of nitroglycerin to the vascular smooth muscle?
n Answer:cGMP
41. A 40-year-old woman who is a nurse took a blood test at her hospital. The serum studies showed that her HBs antigen was positive. Which study can prove that it was her initial infection by hepatitis B?
n Answer:IgM-HBc antibody
n Comment:IgM is the first antibody to appear in the response to initial exposure to an antigen.