Tag: living organisms and energy production

Questions Related to living organisms and energy production

How many ATP molecules will be produced when one molecule of 3-phosphosphoglyceric acid is completely oxidised : 

  1. 16

  2. 32

  3. 64

  4. 48


Correct Option: A

How many ATP molecules are produced after complete oxidation of one molecule of fructose-1, 6-bis-phosphate ?

  1. 40

  2. 32

  3. 38

  4. 44


Correct Option: A

During photosynthesis 

  1. $O _{2}$ evolved comes from $CO _{2}$

  2. ATP is formed

  3. ATP is not formed

  4. Water is required as medium but it does not take part in photosynthesis


Correct Option: B
Explanation:

Photosynthesis is an anabolic process, which helps in forming ATP, where it is called as energy currency. During the light reaction photophosphorylation takes place producing ATP and $NADPH _2$ which is used as energy source for dark reaction.

ATP synthesis proposed by Peter Mitchell is 

  1. Phosphorylation

  2. Photophosphorylation

  3. Oxidative phosphorylation

  4. Chemiosmotic synthesis


Correct Option: D
Explanation:

Peter Mitchell proposed a theory to explain the production of ATP which is 'Mitchell's chemiosmotic coupling hypothesis'. According to this theory:

  1. Inner membrane of mitochondria acts as a transducer of energy and converts energy to chemical energy of ATP along the electrochemical gradient.
  2. Inner mitochondrial membrane is impermeable to NADH, ATP, H+, OH-.
  3. ATP synthesis and electron transport are coupled with proton gradient.
So the answer is 'Chemiosmotic synthesis'.

Energy required to synthesise ATP from ADP and inorganic phosphate is

  1. 2500 cal

  2. 7600 cal

  3. 12000 cal

  4. 20000 cal


Correct Option: B

ATP is injected in cyanide poisoning because it is

  1. Necessary for cellular functions

  2. Necessary for $Na^+$ - $K^+$ pump

  3. $Na^+$ - $K^+$ pump operates at the cell membranes

  4. ATP breaks down cyanide


Correct Option: A

Chemiosmotic hypothesis given by Peter Mitchell proposes the mechanism of

  1. Synthesis of ATP.

  2. Synthesis of FADH$ _2$.

  3. Synthesis of NADH.

  4. Synthesis of NADPH.


Correct Option: A
Explanation:

Peter Mitchell proposed a hypothesis known as the chemiosmotic hypothesis that an electrochemical concentration gradient of protons across a membrane could be utilized to make ATP. He linked this process to osmosis, the diffusion of water across a membrane, this is the reason it is called chemiosmosis.

So the correct option is 'Synthesis of ATP'.

Light reaction in stroma lamellae of chloroplast results in the production of

  1. ATP

  2. NADPH$ _2$

  3. ATP + NADPH$ _2$

  4. O$ _2$


Correct Option: C
Explanation:

A) Along with ATP, ${ NADPH } _{ 2 }$ is also produced.
B) Along with ${ NADPH } _{ 2 }$, ATP is also produced.

C) The light reaction that takes place in the stroma lamellae is the non-cyclic phosphorylation and ATP and ${ NADPH } _{ 2 }$ are the products.
D) Oxygen is also liberated during the light reaction but is not the main product.
So the correct answer is 'ATP + ${ NADPH } _{ 2 }$'.

ATP does not provide phosphate in the reaction

  1. Glucose Glucose 6-P

  2. Fructose Fructose 6-P

  3. PGAL 1 : 3-diPGA

  4. PEPA Pyruvic acid


Correct Option: C

ATP synthetase of chloroplasts is similar to that of

  1. Mitochondria

  2. Peroxisomes

  3. Golgi bodies

  4. Microsomes.


Correct Option: A
Explanation:

Mitochondria and chloroplast both have:

  • A double membrane surrounding the organelles.
  • Purportedly prokaryotic origins according to the endosymbiotic theory which suggests that mitochondria and chloroplast were once prokaryotic bacteria engulfed by endocytosis in early eukaryotes.
  • Their own circular DNA which codes for certain enzymes required for the chemical reactions that take place in these organelles.
  • Their own 70S ribosomes made up of 50S and 30S subunits to translate proteins
  • The enzyme ATP synthase which utilizes the energy released from the movement of protons across it (proton-motive force) to phosphorylate ADP to ATP. (Thus, another similarity would be that they both produce ATP)
  • Electron transport chains, which are embedded in the inner mitochondrial membrane and thylakoid membrane in mitochondria and chloroplasts respectively.
So, the correct option is 'Mitochondria'.