Tag: the need for energy in living organism

Questions Related to the need for energy in living organism

Which is true about the end products of glycolysis?
bio-chemistry respiration in organisms glucose metabolism the need for energy in living organism respiratory function

  1. $2\,pyruvic \,acid+2ATP+{2NADH} _{2}$

  2. $2\,pyruvic \,acid+{2NADH} _{2}$

  3. $1\,pyruvic \,acid+2ATP+{2NADH} _{2}$

  4. $2\,pyruvic \,acid+1ATP+{1NADH} _{2}$

Show answer
Correct Option: A
Explanation:
In glycolysis, two molecules of ATP are consumed during two phosphorylation reactions to form fructose 1, 6-biphosphate. In return, four molecules of ATP are produced by substrate-level phosphorylation (conversion of 1, 3-biphosphoglycerate to 3-phosphoglycerate and phosphoenolpyruvate to pyruvate). Two molecules of ${NADH} _{2}$ are formed at the time of oxidation of glyceraldehyde 3-phosphate to 1, 3-biphosphoglycerate. The net reaction of glycolysis is as follows:

$Glucose+{2NAD}^{+}+2ADP+{2H} _{3}{PO} _{4}\rightarrow2Pyruvate+2NADH+{2H}^{+}+2ATP$

Each NADH is equivalent to 3 ATP, so the net gain in glycolysis is 8 ATP.

So the correct answer is '$2\,pyruvic \,acid+2ATP+{2NADH} _{2}$'.

In glycolysis, glucose molecule is converted into which substance?

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

  1. Lactic acid

  2. Ethanol

  3. Pyruvate

  4. Amino acid

Show answer
Correct Option: C
Explanation:

The process by which the glucose (6C compound) is split into two molecules of pyruvic acid (3C compound) is called glycolysis or EMP pathway. It occurs in the cytoplasm. In glycolysis, 4ATP and 2NADH$ _2$ molecules are formed and 2ATP molecules are consumed in hexose phase

So, the correct answer is 'Pyruvate'

For the start of respiration, a living cell requires

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

  1. Glucose

  2. Glucose + $O _2$

  3. $O _2$

  4. Glucose + ATP

Show answer
Correct Option: D
Explanation:

The mechanism of respiration is initiated by breaking down glucose to pyruvic acid without the help of oxygen. The initial process occurs in the cytosol of cells which requires glucose as well as ATP molecules which provide energy for the process to start. This initial process is known as glycolysis and it takes place in 10 steps in which total 4 ATP molecules are produced and 2 ATP molecules are consumed. Thus, these are the net production of 2 ATP molecules. 

Thus, the correct answer is option D. 

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’.