Tag: bio-chemistry

Quizzes (82) Questions (1918)

Questions Related to bio-chemistry

Multiple choice bio-chemistry biological oxidation chemiosmotic hypothesis living organisms and energy production mechanism of photosynthesis

The energy-carrying compound in the living cell is ATP.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

ATP captures chemical energy obtained from the breakdown of food molecules and its hydrolysis (ATP to ADP + Pi or ADP to AMP + Pi) releases energy that can be used to drive various energy-requiring processes in cells. So, the correct option is 'True'.

Multiple choice bio-chemistry biological oxidation chemiosmotic hypothesis living organisms and energy production mechanism of photosynthesis

Choose the correct answers from the alternatives given .
Energy coupling of endergonic and exergonic reactions within cells

  1. Permits biological reactions to proceed at temperatures consistent with life

  2. Uses heat released by one reaction to fuel the other reaction

  3. Utilizes ATP to carry energy between the exergonic and endergonic reactions

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Energy coupling is the use of an exergonic process to carry out an endergonic process. The energy released in an exergonic process is used to develop an endergonic process. The ATP is responsible for mediating the energy coupling of cells, it is the energy currency. It is used to boost many cellular reactions that require energy. This also provides the energy required for reactions without too much increase in temperature. 
So, the correct option is 'All of the above'.
Multiple choice bio-chemistry biological oxidation chemiosmotic hypothesis living organisms and energy production mechanism of photosynthesis

Read the given statements and select the correct option. 
Statement 1 : In photosynthesis, during ATP synthesis, protons accumulate in the lumen of thylakoid.
Statement 2 : In respiration, during ATP synthesis, protons accumulate in the intermembrane space of mitochondria. 

  1. Both statement 1 and 2 are correct

  2. Statement 1 is correct but statement 2 is incorrect.

  3. Statement 1 is incorrect but statement 2 is correct

  4. Both statement 1 and 2 are incorrect
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Photolysishappens in the thylakoids, producing H+ ions inside the thylakoid membrane., a gradient of hydrogen ions will form across the membrane, ATP synthase take the advantage of this gradient, by allowing hydrogen ions to leak out of the membrane capturing their energy and phosphorylating ADP into ATP, while another statement is correct for mitochondria.

So, the correct option is 'Both statement 1 and 2 are correct'.

Multiple choice bio-chemistry biological oxidation chemiosmotic hypothesis living organisms and energy production mechanism of photosynthesis

Select the correct option:

Study the following statements regarding chemiosmotic hypothesis in mitochondria and select the correct ones.
(i) ${F} _{1}$ headpiece contains the site for the syntesis of ATP from ADP+Pi.
(ii) ${F} _{0}$ part forms the channel through which protons cross the inner membrane.
(iii) For each ATP produced, ${2H}^{+}$ pass through ${F} _{0}$ from the intermembrane space to the matrix down the electrochemical proton gradient.

  1. (i) and (ii)

  2. (ii) and (iii)

  3. (i) and (iii)

  4. (i),(ii) and (iii)
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

  In the given question, the correct statements are as follows:

(i) F1 headpiece contains the site for the synthesis of ATP from ADP+Pi.

(ii) F0 part forms the channel through which protons cross the inner membrane.

(iii) For each ATP produced, 2H+ pass through F0 from the intermembrane space to the matrix down the electrochemical proton gradient.

So, the correct answer is '(i),(ii) and (iii)'.

Multiple choice bio-chemistry biological oxidation chemiosmotic hypothesis living organisms and energy production mechanism of photosynthesis


During chemiosmotic synthesis of ATP, protons diffuse through $CF {0}$ channels that activates ATPase enzyme. As a result, one molecule of ATP is formed when _______ passes through ATPase. 

  1. $4H^{+} $
  2. $H^{+} $
  3. $2H^{+} $
  4. $6H^{+} $
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

During chemiosmotic synthesis of ATP, protons diffuse through CFo channels that activates ATPase enzyme. As a result, one molecule of Atp is formed when two hydrogen ions pass through ATPase.

So, the correct option is '$2H^+$.

Multiple choice bio-chemistry biological oxidation chemiosmotic hypothesis living organisms and energy production mechanism of photosynthesis

Which one respiratory complex is coupled with ETS for ATP synthesis?

  1. Complex I

  2. Complex III

  3. Complex IV

  4. Complex V
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

ATP synthase is also called complex V. It is the final enzyme in the oxidative phosphorylation pathway and utilizes the energy stored in a proton gradient across a membrane to drive the synthesis of ATP from ADP and phosphate (Pi).

So, the correct option is 'Complex V'.

Multiple choice bio-chemistry biological oxidation chemiosmotic hypothesis living organisms and energy production mechanism of photosynthesis
Breakdown of proton gradient developed during chemiosmosis leads to a halt in the release of 

  1. Oxygen

  2. electrons

  3. Energy

  4. Protons
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

According to the chemiosmotic theory of Peter Mitchell, a proton gradient created by the ETS across the membrane leads to the passive movement of protons from the intermembrane space into the matrix or the stroma, through ATP synthase present on the inner membrane. The passive energy released by the protons is used for the synthesis of ATP from ADP. If a proton gradient breaksdown there will be no synthesis of ATP and no movement of protons across the membrane.

So, the correct answer is 'Energy'

Multiple choice bio-chemistry biological oxidation chemiosmotic hypothesis living organisms and energy production mechanism of photosynthesis

Which of the following is an incorrect combination of organism with its chromosome number in mieocyte and in gamete?

  1. Onion, $24, 12$
  2. Ophioglossum, $1260, 630$
  3. Human beings, $46, 23$
  4. Fruit fly, $8, 4$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Chromosome number in meiocyte $(2n)$ of onion cell is $32$, while chromosome number in gamete $(n)$ is $16$.