MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
This section includes 697 Mcqs, each offering curated multiple-choice questions to sharpen your Biology knowledge and support exam preparation. Choose a topic below to get started.
| 151. |
The LDL contains which aproprotein? |
| A. | A |
| B. | B-48 |
| C. | B-100 |
| D. | C |
| E. | E |
| Answer» D. C | |
| 152. |
Which of the following substances decreases the activity of hormone-sensitive lipase? |
| A. | adrenaline |
| B. | thyroxine |
| C. | serotonin |
| D. | TSH |
| E. | prostaglandin E |
| Answer» F. | |
| 153. |
Regarding cellular metabolism of cholesterol: |
| A. | it inhibits HMG-CoA red??? |
| B. | is processed in part to other cholesterol esters by the enzyme acetyl CoA ??? acyltransferase |
| C. | it inhibits the formation of CO2 receptors |
| D. | all of the above |
| E. | none of the above |
| Answer» E. none of the above | |
| 154. |
Chromium deficiency leads to: |
| A. | insulin resistance |
| B. | hypogondal dwarfism |
| C. | anaemia |
| D. | changes in ossification |
| E. | thyroid disorder |
| Answer» B. hypogondal dwarfism | |
| 155. |
Vitamin B1 (thiamine) deficiency leads to: |
| A. | anaemia |
| B. | beri beir |
| C. | convulsions |
| D. | dermatitis |
| E. | pellagra |
| Answer» C. convulsions | |
| 156. |
Which of the following is NOT produced by the citric acid cycle? |
| A. | CO2 |
| B. | H+ ions |
| C. | NAD+ |
| D. | GTP (guanosine triphosphate) |
| E. | NADH |
| Answer» D. GTP (guanosine triphosphate) | |
| 157. |
Which of the following phosphate compounds is MOST important in the production of energy? |
| A. | AMP (adenosine monophosphate) |
| B. | ADP (adenosine diphosphate) |
| C. | ATP (adenosine triphosphate) |
| D. | GTP (guanosine triphosphate) |
| E. | CTP (cytidine triphosphate) |
| Answer» D. GTP (guanosine triphosphate) | |
| 158. |
Regarding fat metabolism, which statement is CORRECT? |
| A. | ketone bodies accumulate in DKA due to a lack of acetyl-CoA substrate |
| B. | fatty acids are transported in the plasma bound to lipoprotein complexes |
| C. | cholesterol is transported from extra-hepatic cells to the liver by high-density lipoproteins (HDLs) in the endogenous pathway |
| D. | eicosanoids are synthesised from cholesterol |
| Answer» D. eicosanoids are synthesised from cholesterol | |
| 159. |
Insulin: |
| A. | binds to GLUT 1-5 receptors in the peripheral tissues |
| B. | deficiency results in increased gluconeogenesis |
| C. | has a plasma half-life of 2-3 hours |
| D. | is secreted by the pancreatic A cells |
| Answer» F. | |
| 160. |
Thyroxine: |
| A. | is mostly bound to albumin in the plasma, since this has the largest capacity |
| B. | is 2-5 times more potent that triiodothyronine (T3) |
| C. | stimulates TSH release |
| D. | 33% is deiodinated in the liver to T3 |
| Answer» E. | |
| 161. |
All but one of the following compounds releases large amounts of energy on breakdown: |
| A. | cAMP |
| B. | ATP |
| C. | creatine phosphate |
| D. | ADP |
| Answer» B. ATP | |
| 162. |
Effects of electrolyte changes: |
| A. | PR interval increases in hyperkalaemia |
| B. | in hyperkalaemia, the heart stops in systole |
| C. | hypercalcaemia causes prolongation of the ST segments |
| D. | hypernatraemia is associated with low voltage electrocardiographic complexes |
| E. | magnesium counteracts digitalis toxicity |
| Answer» F. | |
| 163. |
With respect to calcium metabolism / bone formation: |
| A. | osteoclasts secrete alkaline phosphatase |
| B. | osteoblasts are haemopoietic derivatives of monocyte lineage |
| C. | 1,25(OH)2 ???D3 and PTH stimulate both osteoblasts and osteoclasts |
| D. | oestrogens are thought to be protective of osteoporosis as their main effect is osteoblasts stimulation |
| Answer» D. oestrogens are thought to be protective of osteoporosis as their main effect is osteoblasts stimulation | |
| 164. |
Small intestine: |
| A. | the ligament of Treitz the jejunum becomes the ileum |
| B. | the distance pylorus to ileocecal valve in living humans is 700cm |
| C. | malabsorption syndrome may develop if 25% of the small intestine is removed |
| D. | colonic peristalsis is the first smooth muscle action of the GIT to return after abdominal operation |
| Answer» F. | |
| 165. |
Daily water turnover in the gastrointestinal tract: |
| A. | the stomach contributes about 2500ml resorption |
| B. | jejunum resorbs 1300ml of the water |
| C. | the colon absorbs the bulk of the water load |
| D. | the ??? toxin causes achenyl cyclase therefore cAMP and Clsecretion, ??? |
| E. | stool balance (average) is 500ml |
| Answer» E. stool balance (average) is 500ml | |
| 166. |
A calorie is: |
| A. | standard unit of heat energy necessary to raise the temperature of 1L of water 1 from 15-16 C |
| B. | standard unit of heat energy necessary to raise the temperature of 1gm of mercury 1 from 17-18 C |
| C. | the standard unit of heat energy necessary to raise the temperature of 1gm of water 1 from 17-18 C |
| D. | the standard unit of heat energy necessary to raise the temperature of 1gm of water 1 from 15-16 C |
| Answer» E. | |
| 167. |
Regarding thyroid hormones: |
| A. | little T3 is produced peripherally by deiodination T4 |
| B. | albumin has more capacity to bind thyroid hormones than TBG |
| C. | TBG has less affinity for thyroid hormone than albumin |
| D. | thyroid hormones stimulate lipogenesis |
| Answer» C. TBG has less affinity for thyroid hormone than albumin | |
| 168. |
Regarding the respiratory quotient: |
| A. | it is the ratio of CO2 to O2 at any time |
| B. | RQ of fat is 0.8 |
| C. | increases with hyperventilation |
| D. | increases in metabolic alkalosis |
| Answer» F. | |
| 169. |
Which is NOT a high energy compound? |
| A. | CoA |
| B. | GGP |
| C. | ITP |
| D. | creatine phosphate |
| Answer» C. ITP | |
| 170. |
Regarding basal metabolic rate: |
| A. | it is higher in women |
| B. | it is determined at rest within 12 hours after the last meal |
| C. | increases by 18% for each 1 C of fever |
| D. | is about 40Kcal/m2/h in an average man |
| Answer» E. | |
| 171. |
In a fasting adult at rest: |
| A. | skeletal muscle metabolises mainly glucose |
| B. | the brain accounts for approximately 40% of glucose utilised |
| C. | blood glucose concentrations are higher in women than in men |
| D. | blood glucose levels are maintained initially by hepatic glycogenolysis |
| E. | ketones are absent from plasma |
| Answer» E. ketones are absent from plasma | |
| 172. |
Which is NOT produced by the citric acid cycle? |
| A. | NAD+ |
| B. | CO2 |
| C. | GTP |
| D. | FADH2 |
| Answer» B. CO2 | |
| 173. |
Regarding carbohydrate metabolism: |
| A. | glucokinase is increased in starvation |
| B. | the breakdown of glycogen is called glycolysis |
| C. | the direct oxidative pathway involves the breakdown of glucose through triose |
| D. | the conversion of pyruvate to acetyl-CoA is irreversible |
| Answer» E. | |
| 174. |
Regarding phosphorylase: |
| A. | it clea???? 1:6 linkages in glycogen |
| B. | it is activated by norepinephrine |
| C. | phosphorylase kinase is directly activated by cyclic AMP |
| D. | activation of protein kinase A inhibits glycogen synthesis |
| Answer» E. | |
| 175. |
Which amino acid is not found in protein? |
| A. | ornithine |
| B. | arginine |
| C. | valine |
| D. | aspartic acid |
| E. | -Alanine |
| Answer» F. | |
| 176. |
Regarding vitamin B12 |
| A. | it is a fat soluble vitamin |
| B. | its absorption is inhibited by trypsin |
| C. | it is mainly carried in plasma by attachment to albumin |
| D. | it undergoes enterohepatic circulation |
| E. | none of the above are true |
| Answer» E. none of the above are true | |
| 177. |
Regarding electrolyte absorption: |
| A. | cholera toxin binds to adenosine diphosphate ribose to the subunit of Gs, stimulative ATPase activity |
| B. | active transport of Na+ into the small intestine enterocytes is coupled with the absorption of glucose |
| C. | magnesium sulphate absorption is coupled with Na+ -K+ -ATPase pump |
| D. | the Na+ -K+ ATPase pumps are located at the luminal membrane of the enterocyte |
| Answer» F. | |
| 178. |
Vitamins co-transported with Na+ include all EXCEPT: |
| A. | thiamine |
| B. | folate |
| C. | niacin |
| D. | riboflavin |
| E. | pyridoxine |
| Answer» C. niacin | |
| 179. |
Fat soluble vitamins include all EXCEPT: |
| A. | vitamin A |
| B. | vitamin C |
| C. | vitamin D |
| D. | vitamin E |
| E. | vitamin K |
| Answer» C. vitamin D | |
| 180. |
The largest daily volume of secretions in the GIT originates in the: |
| A. | salivary glands |
| B. | stomach |
| C. | gallbladder (bile) |
| D. | pancreas |
| E. | intestine |
| Answer» C. gallbladder (bile) | |
| 181. |
Iron: |
| A. | most dietary iron is in the ferrous state |
| B. | most iron is absorbed in the upper small intestine |
| C. | a ferritin micelle contains 1,000 atoms of iron |
| D. | 90% of body iron is in haemoglobin |
| E. | 10% of dietary iron is normally absorbed |
| Answer» C. a ferritin micelle contains 1,000 atoms of iron | |
| 182. |
Creatinuria can occur in all EXCEPT: |
| A. | healthy children |
| B. | pregnant women |
| C. | starvation |
| D. | hypothyroidism |
| E. | poorly controlled diabetes mellitus |
| Answer» E. poorly controlled diabetes mellitus | |
| 183. |
Cations in normal (fasting) gastric juice include all EXCEPT: |
| A. | Na+ |
| B. | Ca++ |
| C. | K+ |
| D. | Mg++ |
| E. | H+ |
| Answer» C. K+ | |
| 184. |
Ketone bodies: |
| A. | are not formed under normal conditions |
| B. | are all moderately strong acids |
| C. | are formed when intracellular glucose is deficient |
| D. | are easily metabolised in the liver |
| E. | all of the above |
| Answer» D. are easily metabolised in the liver | |
| 185. |
Stimulation of the right vagus: |
| A. | increases calcium inflow to the SA node |
| B. | decreases calcium inflow to the AV node |
| C. | increases potassium outflow in the SA node |
| D. | increases potassium outflow in the AV node |
| E. | decreases potassium outflow in the SA node |
| Answer» D. increases potassium outflow in the AV node | |
| 186. |
Starling s Law: |
| A. | defines a linear relationship between wall tension and force of contraction of cardiac muscle |
| B. | is approximated by representing wall tension as preload and force of contraction as afterload |
| C. | predicts greater force of contraction when filling pressure is decreased (eg during shock) |
| D. | is explained by an increased availability of intracellular Ca2+ |
| E. | describes heterometric autoregulation |
| Answer» F. | |
| 187. |
The least frequent ABO gene is: |
| A. | A |
| B. | B |
| C. | O |
| D. | AB |
| E. | ABO |
| Answer» C. O | |
| 188. |
Which is absorbed mainly in the colon? |
| A. | short chain fatty acids |
| B. | calcium |
| C. | vitamin K |
| D. | oligosaccharides |
| Answer» B. calcium | |
| 189. |
Which is a water soluble vitamin? |
| A. | D |
| B. | B12 |
| C. | A |
| D. | K |
| Answer» C. A | |
| 190. |
Which is not Na+ dependent for absorption? |
| A. | thiamin |
| B. | riboflavin |
| C. | niacin |
| D. | folate |
| Answer» E. | |
| 191. |
Which is NOT an action of CCK? |
| A. | gallbladder contraction |
| B. | increased gastric motility and emptying |
| C. | glucagon secretion |
| D. | secretion of pancreatic juice |
| Answer» C. glucagon secretion | |
| 192. |
Which is INCORRECT regarding nerve supply to the gut? |
| A. | the blood vessels are known to have enteric, parasympathetic and sympathetic innervation |
| B. | the myenteric plexus lies between the longitudinal and circular muscle layers |
| C. | parasympathetic supply is via vagal and sacral nerve |
| D. | sympathetic supply is often inhibitory on cholinergic postganglionic fibres |
| Answer» B. the myenteric plexus lies between the longitudinal and circular muscle layers | |
| 193. |
The actions of gastrin include all but: |
| A. | insulin secretion in response to a carbohydrate meal |
| B. | a trophic effect on colonic mucosa |
| C. | a trophic effect on gastric mucosa |
| D. | pepsin secretion |
| Answer» B. a trophic effect on colonic mucosa | |
| 194. |
Gastrin secretion is stimulated by all but: |
| A. | luminal peptides |
| B. | vagal discharge |
| C. | luminal acid |
| D. | phenylalanine |
| Answer» D. phenylalanine | |
| 195. |
Which produces the majority of salivary volume? |
| A. | lingual glands |
| B. | sublingual |
| C. | parotid |
| D. | submandibular |
| Answer» E. | |
| 196. |
Which hormone is most important in insulin secretion? |
| A. | gastrin |
| B. | CCK |
| C. | GIP |
| D. | secretin |
| Answer» D. secretin | |
| 197. |
Which nerve is NOT involved in the efferent (motor) swallow reflex? |
| A. | trigeminal |
| B. | vagus |
| C. | facial |
| D. | hypoglossal |
| Answer» C. facial | |
| 198. |
Chief cells secrete: |
| A. | HCl |
| B. | pepsinogen |
| C. | intrinsic factor |
| D. | HCO3- |
| Answer» C. intrinsic factor | |
| 199. |
Which is NOT part of the normal content of gastric juice? |
| A. | HPO4 2- |
| B. | mucus |
| C. | lipase |
| D. | amylase |
| Answer» E. | |
| 200. |
Which stimulates parietal cell secretion? |
| A. | prostaglandins |
| B. | aspirin |
| C. | vinegar |
| D. | acetylcholine |
| Answer» E. | |