All Free Biology MCQs with Answers
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19,844 questions · page 901 of 993
18001. Unit of carbohydrate is?
- A. Monosaccharides
- B. Amino acids
- C. Fatty acids
- D. All
Explanation: Monosaccharide: The most basic, fundamental unit of a carbohydrate. These are simple sugars with the general chemical structure of C6H12O6.
Correct answer: Monosaccharides- A. Enzymes
- B. Coenzymes
- C. Vitamins
- D. Antibiotics
Explanation: Metabolically-important species that include phosphorylated ribose include ADP, ATP, coenzyme A, and NADH. Thus, option B is correct.
Correct answer: Coenzymes- A. Starch
- B. Cellulose
- C. Glycogen
- D. All of these
Explanation: Out of all the options, the most abundant carbohydrate in animals is glycogen.
Correct answer: Glycogen- A. Ventricular systole
- B. Ventricular diastole
- C. Atrial systole
- D. Atrial diastole
- E. Both during atrial systole and atrial diastole
Explanation: Explanation for this question will be added soon.
Correct answer: Ventricular systole- A. Purkinje fibers
- B. AV bundle
- C. Sinoatrial node
- D. Bundle of His
Explanation: The impulse starts in a small bundle of specialised cells located in the right atrium, called the SA node.
Correct answer: Sinoatrial node- A. The formation of carbon dioxide
- B. The oxidation of cytochrome
- C. The reduction of oxygen to water
- D. The synthesis of ATP
Explanation: c) The reduction of oxygen to water:The reduction of oxygen to water is the final reaction in aerobic respiration.
Correct answer: The reduction of oxygen to water- A. 2
- B. 4
- C. 8
- D. 10
- E. 7
Explanation: Explanation for this question will be added soon.
Correct answer: 2- A. Lactic acid
- B. Ethyl alcohol
- C. Carbon dioxide and water
- D. Acetyl CoA
- E. Both C and D
Explanation: Explanation for this question will be added soon.
Correct answer: Both C and D- A. ATP
- B. GTP
- C. NADPH2
- D. FADH2
- E. NAD
Explanation: Explanation for this question will be added soon.
Correct answer: FADH2- A. 4 carboxylic compounds are produced
- B. 3 carboxylic compounds are produced
- C. Citric acid contain 4 carboxyl groups
- D. Citric acid contain 3 carboxyl groups
- E. None of above
Explanation: Explanation for this question will be added soon.
Correct answer: Citric acid contain 3 carboxyl groups- A. 2 ATP
- B. 3 ATP
- C. 4 ATP
- D. 5 ATP
Explanation: During cellular respiration, NADH (nicotinamide adenine dinucleotide) is an important electron carrier that plays a key role in generating…
Correct answer: 3 ATP- A. When Isocitrate is converted into alpha - ketoglutarate
- B. When alpha - Ketogluterate is converted into Succinate
- C. When Succinate is converted into Fumarate
- D. When Fumarate is converted into Maltose
Explanation: Succinate converts into fumarate using the enzyme succinate dehydrogenase and [FAD] is reduced to [FADH2] which is a prosthetic group of…
Correct answer: When Succinate is converted into Fumarate- A. 1 ATP
- B. 2 ATP
- C. 3 ATP
- D. 4 ATP
Explanation: The oxidation of one molecule of NADH thus leads to the synthesis of three molecules of ATP, whereas the oxidation of FADH2, which enters…
Correct answer: 3 ATP18014. NADH produces how many ATP?
- A. 2 ATP
- B. 3 ATP
- C. 4 ATP
- D. 6 ATP
Explanation: NADH can produce 3 ATP molecules. FADH can produce 2 ATP molecules.
Correct answer: 3 ATP- A. Cytochrome oxidases
- B. Dehydrogenases
- C. Hydrolases
- D. Nucleases
Explanation: Cyanide poisons the mitochondrial electron transport chain within cells and renders the body unable to derive energy (adenosine…
Correct answer: Cytochrome oxidases18016. If oxygen is available, the complete breakdown of glucose produces _ ATP molecules in proka,yotos.
- A. 201
- B. 36
- C. 38
- D. 40
Explanation: A total 38 ATP molecules (2 ATP molecules from glycolysis, 2 from Krebs cycle and 34 from electron transport system) are produced per…
Correct answer: 38- A. Fatty acids, Polysaccharides
- B. Protein, Amino acids
- C. Lipids, Glucose
- D. None of these options are correct
Explanation: CATABOLISM: It is the breakdown of complex molecules in living organisms to form simpler ones, together with the release of energy…
Correct answer: Protein, Amino acids18018. The biochemical process used in the synthesis of alcohol in the presence of yeast is called as _ ?
- A. Respiration
- B. Photosynthesis
- C. Fermentation
- D. Aerobic respiration
Explanation: Fermentation is a process of central metabolism in which an organism converts a carbohydrate, such as starch or sugar, into an alcohol or…
Correct answer: Fermentation18019. Respiration involves the
- A. Chemical process
- B. Biochemical process
- C. Mechanical process
- D. Both B and C
Explanation: Respiration is a biochemical process, in which the cells of an organism obtain energy by reacting oxygen with glucose, resulting in the…
Correct answer: Biochemical process- A. 4.5
- B. 5.5
- C. 7.5
- D. 6.7
Explanation: Because in anaerobic reaction only glycolysis takes placse in which glucose is given 2 ATP and then at the end pyruvate is formed with 4…
Correct answer: 5.5