Tag: respiration in organisms

Questions Related to respiration in organisms

How many ATP are produced in mitochondria on complete oxidation of glucose?

bio-chemistry respiration in organisms glucose metabolism the need for energy in living organism respiratory function

  1. $24$

  2. $30$

  3. $34$

  4. $38$

Show answer
Correct Option: A
Explanation:
Name of process   Site  Total ATP formation
 Glycolysis  Cytoplasm  2NADH(i.e. 6ATP)+ 2ATP = 8ATP 
 Conversion of pyruvate to acetyl CoA  Cytoplasm  2NADH = 6ATP
 Kreb's cycle  Mitochondria  6NADH + 2 FADH + 2GTP= 18ATP +4ATP + 2ATP  = 24 ATP

 1 NADH = 3 ATP, 1 FADH = 2 ATP

So, the correct answer is '$24$'

When one molecule of sucrose is subjected to phosphorylation how many ATPs are consumed?

bio-chemistry respiration in organisms glucose metabolism the need for energy in living organism respiratory function

  1. 2

  2. 6

  3. 3

  4. 4

Show answer
Correct Option: A
Explanation:

During the conversion of fructose-1,6-bis-phosphate to lactate, the pathway generates a total of four molecules of ATP, resulting in a net yield of two ATP per glucose consumed.

correct answer is A.

In which of the following steps dehydrogenate occurs? 

bio-chemistry respiration in organisms glucose metabolism the need for energy in living organism respiratory function

  1. glucose $\rightarrow$ glucose 6-phosphate

  2. 3 - PGA $\rightarrow$ 2 - PGA

  3. PEPA $\rightarrow$pyruvate

  4. PGAL $\rightarrow$ 1, 3diPGA

Show answer
Correct Option: A
Explanation:
The G6PDwhich is glucose dehydrogenate gene provides instructions for making an enzyme called glucose-6-phosphate dehydrogenase. This enzyme, which is active in virtually all types of cells, is involved in the normal processing of carbohydrates. This enzyme helps protect red blood cells from damage and premature destruction.
So, the correct answer is glucose $\rightarrow$ glucose 6-phosphate

Match the scientist and their discoveries given in Column I and II correctly and choose the correct combination from the following.

   List I    List II
 A  P Mitchell  p  Pentose phosphate pathway
 B  Warberg and Dickens  q  Chemiosmotic mechanism
 C  EMP pathway  r  Embden-Meyerhof and Parnas
 D  Anaerobic respiration  s  Pasteur
     t  Kostychev
bio-chemistry respiration in organisms glucose metabolism the need for energy in living organism respiratory function

  1. A- p, B- q, C- r, D- t

  2. A- q, B- p, C- s, D- t

  3. A- q B- p, C- r, D- t

  4. A- q, B- p, C- t, D- s

Show answer
Correct Option: C
Explanation:

Peter Dennis Mitchell was a British biochemist, who was awarded the 1978 Nobel prize for chemistry for his discovery of the 'chemiosmotic mechanism' of ATP synthesis.
Pentose phosphate pathway was discovered by Warburg and Dickens. It is a pathway of hexose oxidation in which glucose-6-phosphate undergoes two successive oxidations by NADP, the final one being oxidative decarboxylation to form a pentose phosphate.
EMP pathway is known as 'Embden-Meyerhof-Parnas pathway'. It is also called as glycolysis. It converts glucose to pyruvate.
Kostychev was first Russian scientist to explain anaerobic respiration. He applied his knowledge of microbiology to the study of the decomposition of organic matter in the soil. Thus, the correct answer is option C.

In pentose phosphate pathway, which of the following process is lacking?

bio-chemistry respiration in organisms glucose metabolism the need for energy in living organism respiratory function

  1. Kreb's cycle

  2. Glycolysis

  3. Oxidative phosphorylation

  4. All of the above

Show answer
Correct Option: D
Explanation:

The pentose phosphate pathway also called the hexose monophosphate shunt, is a shunt from glycolysis designed to produce either NADPH or ribose or both. There are two distinct phases in the pathway. The first is the oxidative phase, in which NADPH is generated, and the second is the non-oxidative synthesis of 5-carbon sugars. In the pentose phosphate pathway, glucose 6-phosphate is directly oxidized without entering glycolysis. Even Kreb's cycle and oxidative phosphorylation doesn't happen in pentose phosphate pathway.

So, the correct answer is 'All of the above'.


The pentose phosphate pathway (PPP) of most organisms take place in

bio-chemistry respiration in organisms glucose metabolism the need for energy in living organism respiratory function

  1. Mitochondria

  2. Cytoplasm

  3. Chloroplast, peroxisome and mitochondrion

  4. Chloroplast, glyoxysome and mitochondrion

  5. Chloroplast, lysosome and mitochondrion

Show answer
Correct Option: B
Explanation:

Pentose phosphate pathway is also called as phosphogluconate pathway or Hexose Monophosphate Shunt (HMP Shunt). It occurs in most organisms in cytoplasm. It results in generation of NADPH, ribose-5-phosphate (R5P) and erythrose 4-phosphate (E4P). R5P is precursor for the synthesis of nucleotides. E4P is involved in the synthesis of aromatic amino acids. 

Thus, the correct answer is option B.

During the complete oxidation of one glucose, how many reduced coenzymes are produced due to following processes?
(A) Link reaction
(B) Glycolysis
(C) Krebs cycle
Choose the correct option from the following.

bio-chemistry respiration in organisms glucose metabolism the need for energy in living organism respiratory function

  1. $A = 1, B = 1, C = 4$

  2. $A = 2, B = 2, C = 4$

  3. $A = 2, B = 2, C = 3$

  4. $A = 2, B = 2, C = 8$

Show answer
Correct Option: A,D
Explanation:

In the oxidation of one glucose molecule, during aerobic respiration, 2NADH2 in link reaction, 2NADH2 in glycolysis, 8NADH2 in Krebs cycle are formed.

So, the correct option is ‘A=1, B=1, C=4 or A=2, B=2, C=8’.

How many ${ CO } _{ 2 }$ molecules are produced from one pyruvate on complete oxidation :-

bio-chemistry respiration in organisms glucose metabolism the need for energy in living organism respiratory function

  1. 1

  2. 2

  3. 3

  4. 4

Show answer
Correct Option: B
Explanation:

During the complete oxidation of pyruvate, two carbon atoms are lost in the form of CO2 - one during the conversion of isocitrate to alpha-ketoglutarate and the second during the conversion of alpha-ketoglutarate to succinyl CoA.
So, the correct answer is '2'.

Sequence of aerobic metabolic breakdown of glucose is

bio-chemistry respiration in organisms glucose metabolism the need for energy in living organism respiratory function

  1. Glycolysis-transition-citric acid cycle-electron transport system

  2. Transition-glycolysis-electron transport-citric acid cycle

  3. Electron transport system-citric acid cycle- transition-glycolysis

  4. None of the above

Show answer
Correct Option: A
Explanation:

  • For the aerobic respiration the substrate glucose has  to undergo a following set of process 
  • First of which is glycolysis where the molecule of glucose is broken down to 2 molecules of pyruvate.
  • These pyruvate molecules are to be cconverted to Acetyl CoA so that it can enter the mitochondrial membrane and undergo kerb cycle.
  • After being converted to acetyl coA it takes part in kerb cycle where molecules of NADH, FADH and ATP are formed.
  • These NADH, FADH molecules are the electron acceptors which are used in ETS to transport electron and hydrogen ions through the complexs.
  • These electrons and hydrogen ions are used for the formation of ATP via ATP synthase.
  • Therefore the process for the aerobic breakdown of glucose is Glycolysis followed by transition of pyruvate then citric acid cycle which is followed by electron transport system.
  • Therefore the correct answer is 'Glycolysis-transition-citric acid cycle-electron transport system'








How many oxygen atoms are required for the complete oxidation of one molecule of pyruvate?

bio-chemistry respiration in organisms glucose metabolism the need for energy in living organism respiratory function

  1. 2

  2. 5

  3. 4

  4. 3

Show answer
Correct Option: A
Explanation:

Under Anaerobic conditions, Pyruvic Acid enters in matrix of mitochondrion and undergoes oxidative decarboxylation to form 2 carbon energy rich compound called Acetyl Co A.

This process utilizes 2 oxygen atoms. Incomplete oxidation of Pyruvate leads to the formation of lactic acid in muscles and formation of ethyl alcohol in yeast as a process of fermentation.

So, the correct answer is '2'