Tag: respiration

Questions Related to respiration

An enzyme used in pentose phosphate pathway is

hmp shunt alternative to glycolysis carbohydrate metabolism respiration bio-chemistry

  1. RUBP.

  2. Aldolase.

  3. Pyruvate kinase.

  4. Phosphogluconate dehydrogenase.

Show answer
Correct Option: D
Explanation:

In the pentose phosphate pathway 6-Phosphogluconate dehydrogenase (6PGD) is an enzyme that produces NADPH by converting 6-phosphogluconate to ribulose 5-phosphate. NADPH is used for lipid production. Thus the correct answer is option D.

Consider the following statements.


a. The Pentose Phosphate Pathway supplies Erythrose-$4$-Phosphate which is the starting material the synthesis on lignin.
b. The Pentose Phosphate pathway also occurs in plastids.
c. NADPH is generated by the Pentose phosphate pathway

Which of the statements given are correct?

hmp shunt alternative to glycolysis carbohydrate metabolism respiration bio-chemistry

  1. $a$ and $b$ only

  2. $a$ and $c$ only

  3. $b$ and $c$ only

  4. $a, b$ and $c$

Show answer
Correct Option: A

The substrate for pentose phosphate pathway is

hmp shunt alternative to glycolysis carbohydrate metabolism respiration bio-chemistry

  1. Glucose 6-phosphate.

  2. Glucose 1-phosphate.

  3. Fructose 6-phosphate.

  4. Fructose 1-phosphate.

Show answer
Correct Option: A
Explanation:

Pentose Phosphate Pathway runs parallel to glycolysis and takes place in the cytoplasm. The oxidation steps, utilizing glucose-6-phosphate (G6P) as the substrate, occur at the beginning of the pathway and are the reactions that generate NADPH and also give five carbon compound for glycolysis.

So the correct option is 'Glucose 6-phosphate'.

Which one of the following produces more energy per glucose molecule?

hmp shunt alternative to glycolysis carbohydrate metabolism respiration bio-chemistry

  1. Alcoholic fermentation

  2. Glycolysis

  3. Pentose phosphate pathway

  4. Lactic acid fermentation

Show answer
Correct Option: C
Explanation:

Glycolysis is a common pathway between the aerobic and anaerobic respiration. The net amount of ATP formed during glycolysis is two.

Alcoholic fermentation and lactic acid fermentation are both of pathways involved in the anaerobic respiration in which the pyruvic acid formed after glycolysis is converted into lactic acid or ethanol and carbon dioxide. The energy released during anaerobic respiration is much less as compared to the aerobic respiration.
So the correct option is, 'pentose phosphate pathway'

Which of the following pairs of structure and functions are correctly matched?
a. Tendril- Climbing
b. Penumatophore - Respiration
c. Stratospheric - checking UV or beta
d. Ozone shield - UV rays
Select the correct answer using the codes given.

hmp shunt alternative to glycolysis carbohydrate metabolism respiration bio-chemistry

  1. $2$ and $3$ only

  2. $1$ and $2$ only

  3. $1$ and $3$ only

  4. $1, 2$ and $3$

Show answer
Correct Option: A

In hexose monophosphate shunt, the net formation of ATP molecules is

hmp shunt alternative to glycolysis carbohydrate metabolism respiration bio-chemistry

  1. 36

  2. 35

  3. 38

  4. 34

Show answer
Correct Option: A
Explanation:

Hexose monophosphate shunt is an alternative pathway to glycolysis or the tricarboxylic acid cycle for glucose oxidation. It occurs in the cytoplasm and has two phases; the oxidative phase and the non-oxidative phase. 

This is the only process that generates reduced NADPH₂ which act as the reducing agent in the biosynthetic processes.
6 glucose molecules that enter hexose monophosphate shunt, produces 12 NADPH₂ and 6 carbon dioxide.
12 NADPH₂ molecules when undergo ETS forms  36 molecules of ATP.
So, the correct option is '36'


Which of the following is not a pathway that relates to generation of ATP?

hmp shunt alternative to glycolysis carbohydrate metabolism respiration bio-chemistry

  1. Pentose phosphate shunt

  2. Embden-Meyerhof pathway

  3. Oxidative-phosphorylation

  4. Photosynthesis

Show answer
Correct Option: A
Explanation:

  • Pentose phosphate shunt is the pathway that is used for the synthesis of a 5 carbon molecules such as ribose and deoxyriose which can be used for the synthesis of nucleotides, no ATP is produced during this reaction.
  • EMP pathway is the glycolysis process where 2 ATP are produced at the end of the reaction.
  • Oxidative phosporylation is the pathway that is used to reduce the NADH and FADH for the formation of ATP
  • And photosynthesis is the pathway in the plant that is used for the production of the carbohydrates that are used in the catabolic pathway for the synthesis of the ATP in cellular respiration.
  • Therefore the correct answer is option is 'Pentose phosphate shunt'.











Production of $NADPH _2$ is not linked with ATP generation in

hmp shunt alternative to glycolysis carbohydrate metabolism respiration bio-chemistry

  1. Photorespiration

  2. Light recation

  3. Hexose monophosphate pathway

  4. Dark reaction

Show answer
Correct Option: C
Explanation:

Hexose monophosphate pathway (HMP) or pentose phosphate shunt is an alternate glucose metabolism that occurs in adipose tissues, liver, erythrocytes, testes, adrenal glands, mammary glads etc. This pathway is performed to generate the $NADPH _2$ to facilitate the cholesterol synthesis, steroid and lipid production and fatty acid synthesis. Thus signifying that HMP pathway readily takes place in tissues associated with lipogenesis like liver and adipose tissue. It is not linked with ATP generation. Also, the ribose sugars generated are used in DNA and RNA and many nucleotides like $ATP$, $FADH _2$ $CoA$ etc.

Photorespiration, light reaction and dark reaction are associated with phosphorylation.
Hence, the correct answer is 'Hexose monophosphate pathway'

Match the column I and II-

Column-I Column-II Site of pathway
(A) Fatty acid oxidation (p) Cytoplasm
(B) Pyruvate oxidation (q) Mitochondrial matrix
(C) Fatty acid synthesis (r) Mitochondrial inner membrane
(D) Pentose phosphate pathway (s) Glyoxysome
hmp shunt alternative to glycolysis carbohydrate metabolism respiration bio-chemistry

  1. A $\rightarrow$ p, B$\rightarrow$ q, C$\rightarrow$ r, D$\rightarrow$ s

  2. A $\rightarrow$ q, B$\rightarrow$ p, C$\rightarrow$ p, D$\rightarrow$ p

  3. A$\rightarrow$ p, B$\rightarrow$ r, C$\rightarrow$ q, D$\rightarrow$ s

  4. A $\rightarrow$ p, B$\rightarrow$ q, C$\rightarrow$ q, D$\rightarrow$ p

Show answer
Correct Option: B
Explanation:

Answer is B.


A. Fatty acid oxidation - (q) Mitochondrial matrix

B. Pyruvate oxidation  -(p) Cytoplasm
C. Fatty acid synthesis - (p) Cytoplasm
D. Pentose phosphate pathway-(p) Cytoplasm. 

Warburg-Dickens pathway is also known as

hmp shunt alternative to glycolysis carbohydrate metabolism respiration bio-chemistry

  1. P.P.P.

  2. TCA cycle.

  3. EMP pathway.

  4. None of the above.

Show answer
Correct Option: A
Explanation:

Pentose phosphate pathway (PPP) is variously called as Warburg-Dickens pathway and hexose monophosphate shunt. This metabolic pathway had been discovered through a number of experiments of Lippman, Warburg (1935) and Dickens (1938).