Tag: bio-chemistry

Questions Related to bio-chemistry

During which stage in the complete oxidation of glucose are the greatest number of ATP molecules formed from ADP -

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. Glycolysis

  2. Krebs cycle

  3. Electron transport chain

  4. Conversion of pyruvic acid to acetyl CoA

Show answer
Correct Option: C
Explanation:

In glycolysis 4 ATP and 2NADH2 molecules are formed. These 2NADH2  molecules go to electron transport chain. In oxidative decarboxylation no ATP molecule is formed but two molecules of 2NADH2  are formed from two molecules of pyruvate. These two NADH2 go to electron transport chain. In Kreb's cycle 2 ATP, 6NADH2 and 2FADH2 molecules are formed from two molecule of acetyl Co-A. These NADH2 and 2FADH2  go to electron transport chain. In electron transport chain all 2NADH2   and 2FADH2  pass to electron carriers and yield 3 ATP and 2 ATP molecules per 2NADH2   and 2FADH2  respectively. Thus,  4 ATP are formed in glycolysis, 2 ATP in Krebs cycle and 34 ATP from electron transport chain. 40 ATP and 2 ATP molecules are used during glycolysis. So, net gain of ATP molecules during one complete oxidation of a glucose molecule is 38 ATP.


So, the correct answer is 'Electron transport chain'.

The rate of respiration undergoes a sharp rise followed by a when certain fruits ripen. This phenomenon is known as ____________.

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. Climatic rise

  2. Climatic fall

  3. Climacteric rise

  4. Anaerobiosis

Show answer
Correct Option: A

Out of $38$ ATP molecule how many ATP are formed by substrate level phosphorylation by aerobic respiration of $1$ glucose?

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. $2$

  2. $3$

  3. $4$

  4. Zero

Show answer
Correct Option: A
Explanation:

Substrate level phosphorylation involves the conversion of 1,3 bisphosphoglycerate to 3 phosphoglycerate producing ATP.

For 1 molecule of glucose, 2 (1,3 bisphosphoglycerate) are formed, hence 2 ATP are formed.  

Number of ATP molecules formed during aerobic respiration in break down of one glucose molecule via malate aspartate shuttle is 

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. 38

  2. 18

  3. 28

  4. 4

Show answer
Correct Option: A

For the synthesis of 1 ATP in oxidative phosporylation how many ${H}^{+}$ required?

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. $3$

  2. $2$

  3. $4$

  4. $1$

Show answer
Correct Option: C
Explanation:

For synthesis of 1 ATP, 4 H+ are required. ATP synthase synthesizes 1 ATP for every 4 H+ that passes through it. 

During aerobic respiration, all the ATPs are synthesized as a result of _______________.

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. Oxidative phosphorylation

  2. Oxidative and substrate level phosphorylation

  3. Substrate level phosphorylation

  4. Oxidative and phosphorylation

Show answer
Correct Option: A

How many oxygen atoms are utilised during aerobic oxidation of one molecule of acetyl-Co-A?

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. Three

  2. Four

  3. Two

  4. Six

Show answer
Correct Option: A

How many ATP molecules are synthesized in complete aerobic respiration of dipeptide molecule during Amphibolic pathway?

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. $30\ ATP$

  2. $60\ ATP$

  3. $15\ ATP$

  4. $36\ ATP$

Show answer
Correct Option: A

If $4$ molecules of glucose are synthesized during photosynthesis, how many ATP molecules are released and how many molecules of ATP are utilized respectively?

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. $8 ATP, 72 ATP$

  2. $2 ATP, 18 ATP$

  3. $8 ATP, 36 ATP$

  4. $4 ATP, 36 ATP$

Show answer
Correct Option: A
Explanation:
For the synthesis of one molecule of glucose by photosynthesis, 2 ATP molecules are released and 18 ATP molecules are utilized. 18 ATP molecules are utilized in the sense that in most of the plants the mode of CO$ _2$ fixation is C$ _3$ cycle or Calvin cycle. In C$ _3$ cycle for each molecule of CO$ _2$ to be fixed, 3 ATP are required. Thus, for the synthesis of one Glucose molecule, 6 CO$ _2$ molecules are fixed. Thus, 18 ATP molecules in total are utilized for the formation of one Glucose molecule.
Hence, for the synthesis of 4 glucose molecules in photosynthesis,
ATP molecules released = 4 × 2 = 8
ATP molecules utilized = 4 × 18 = 72.
So, the correct answer is A.

Choose the correct answers from the alternatives given :
In eukaryotes complete oxidation of a glucose molecule results in the net gain of how many ATP molecules?

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. 2

  2. 4

  3. 36

  4. 38

Show answer
Correct Option: D
Explanation:

Complete oxidation of glucose occurs through three steps : 

  1. Glycolysis
  2. Krebs cycle
  3. Terminal oxidation
During glycolysis glucose changes to pyruvic acid gaining total energy as 2 ATP molecules and 2 molecules of NADH$ _2$ then later on in Krebs cycle 30 ATP molecules and 2 FADH$ _2$ are produced. One NADH$ _2$ produces 3 ATP molecules while one FADH$ _2$ produces two ATP molecules. Therefore in complete oxidation of one molecule of glucose, a total of 38 ATP's are gained.
So, the correct option is ' 38'.