Tag: biology

Questions Related to biology

The process by which the energy of glucose is released under aerobic respiration was discovered by

  1. Hopkins

  2. Lister

  3. Krebs

  4. Pasteur


Correct Option: C
Explanation:

The process by which the energy of glucose is released under aerobic respiration, was discovered by Hans Krebs. The Krebs cycle is a part of cellular respiration. It is a series of chemical reactions used by all aerobic organisms to generate energy.

Aerobic respiratory pathway is appropriately called as

  1. Anabolic

  2. Catbolic

  3. Amphibolic

  4. Parabolic


Correct Option: C
Explanation:

Aerobic respiratory pathway is appropriately called amphibolic pathway. It contains both catabolic and anabolic reactions. The pathway is catabolic because in this pathway, glucose is broken down into carbon dioxide and water. It is also anabolic pathway as energy rich ATP molecule is produced during this pathway. These ATP molecules are later used to carry out various reaction. 

Thus, the correct answer is option C.

Kerbs cycle __________________.

  1. Liberates a minor part of energy during respiration

  2. Is operative in photorespiration

  3. Reactions are independent of oxygen supply

  4. Is a like between carbohydrate and nitrogen metabolism


Correct Option: A

In Kreb's cycle, OAA accepts acetyl CoA to form 

  1. Citric acid

  2. Oxalosuccinate

  3. Fumarate

  4. Succinyl CoA


Correct Option: A
Explanation:

The citric acid cycle starts with the condensation of acetyl group with oxalo acetic acid and water to yield citric acid. The reaction is catalysed by the enzyme citrate synthase and a molecule of CoA is released.

Image result for citric acid cycle
So the correct option is 'citric acid'.

The site of Krebs cycle is

  1. Cytoplasm

  2. Mitochondrial matrix

  3. Intermembrane space of mitochondria

  4. Racker's particles


Correct Option: B

In Kreb's cycle formation of ___________________.

  1. $34$ ATP takes place

  2. $38$ ATP takes place

  3. $15$ ATP from each acetyl Co-A takes place

  4. $12$ ATP from each acetyl Co-A takes place $(24\ ATP)$


Correct Option: A

How many oxidation step take place during glycolysis, link reaction and Kreb's cycle.

  1. $1, 1 and 1$

  2. $1, 1 and 4$

  3. $1, 1 and 3$

  4. $1, 1 and 8$


Correct Option: B
Respiratory Pathway is _______.
  1. Catabolic

  2. Amphibolic

  3. Anabolic

  4. Endergonic


Correct Option: B
Explanation:

The same respiratory process which acts as a catabolic pathway for respiratory substrates also acts as an anabolic pathway for the synthesis of various intermediary metabolic products and secondary metabolites. The respiratory pathway, therefore, acts both as catabolic as well as an anabolic pathway. Thus, it is better to call it the amphibolic pathway rather than a catabolic pathway alone.

So the correct option is B.

During amphibolic pathway, acetyl Co-A can perform the biosynthesis of 

  1. Amino acid

  2. Gibberellic acid

  3. Fatty acid

  4. All of the above


Correct Option: C
Explanation:

Fatty acid synthesis takes place in the cytoplasm of the cell. It is the creation of fatty acids from acetyl-CoA and NADPH through the action of enzymes called fatty acid synthases. Most of the acetyl-CoA which is converted into fatty acids is derived from carbohydrates via the glycolytic pathway. 

So, the correct option is 'Fatty acid'.

Find the incorrect match (with respect to ATP gain) -

  1. Bacterial cell - $38$ ATP or $2$ ATp

  2. Citric Acid Cycle - $12$ ATP

  3. Nerve cell - $38$ ATP

  4. Liver cell - $38$ ATP


Correct Option: A
Explanation:

The Kreb’s Cycle gives 3 moles of NADH1 mole of FADH and 1 mole of ATP per cycle of substrate i.e per 1 mole of Acetyl CoA. However net ATP i.e after ETS which would make the answer to 12 ATP(9+2+1) respectively.

36 ATPs are produced in Aerobic Respiration involving the complete breakdown of glucose molecule into carbon-dioxide and water using oxygen as final electron aceptor

Complete oxidation of glucose molecule takes place in 3 sequential reactions -

1.Glycolysis occuring in cytoplasm

2.Kreb cycle occuring in mitochondrial matrix

3 Electron transport chain (ETC )and oxidative phosphorylation occuring in inner mitochondrial membrane . So,total number of ATPs produced in aerobic respiration are

Glycolysis - 6/8 ATPs

Link reaction and kreb cycle - 30ATPs

Total -36/38 ATPs.


So, the correct option is 'Option A'.