Tag: bio-chemistry

Quizzes (82) Questions (1918)

Questions Related to bio-chemistry

Multiple choice bio-chemistry biological oxidation oxidative phosphorylation living organisms and energy production glycolysis

Mitochondrial electron transport chain is

  1. Cyclic phosphorylation.

  2. Oxidative phosphorylation.

  3. Noncyclic phosphorylation.

  4. Photooxidation.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The electron is transferred from NADH to oxygen in mitochondria con­sists of four multi-protein complexes is coupled to the synthesis of ATP from ADP and inorganic phosphate (Pi) which is called as oxidative phosphorylation. 

So the correct option is 'Oxidative phosphorylation.'

Multiple choice bio-chemistry biological oxidation oxidative phosphorylation living organisms and energy production glycolysis

Coenzyme $NAD^+$ and FAD are connected with respiratory reactions as they

  1. Are involved in each step of ATP synthesis.

  2. Function in Krebs cycle and terminal oxidative phosphorylation.

  3. Act as hydrogen carrier.

  4. Are reducing agents.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

NAD and FAD plays a major role in cellular respiration,  They carry the H+ and electrons to Electron Transport Chain to convert ADP + Pi ATP.

So the correct option is 'Act as a hydrogen carrier.'

Multiple choice bio-chemistry biological oxidation oxidative phosphorylation living organisms and energy production glycolysis

Glyceraldehyde phosphate is oxidised in glycolysis. The hydrogen atom and electron liberated cause

  1. Oxidation of NAD$^+$.
  2. Reduction of NAD$^+$.

  3. Change in oxaloacetic acid.

  4. Formation of methane.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Glyceraldehyde-3-phosphate is oxidized by the coenzyme nicotinamide adenine dinucleotide (NAD). NAD+ is an oxidizing agent - it accepts electrons from other molecules and becomes reduced.

So the correct option is 'Reduction of NAD+'.

Multiple choice bio-chemistry biological oxidation oxidative phosphorylation living organisms and energy production glycolysis

Which of the following is a biological uncoupler of oxidative phosphorylation?

  1. Thermogenin.

  2. 2, 4-Dichlorophenoxyacetic acid.

  3. 2, 4-Dinitrophenol.

  4. Ethylene diaminotetra-acetic acid.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Brown adipose tissue is rich in mitochondria, containing an uncoupling protein (thermogenin) that uncouples oxidation and phosphorylation of adenosine diphosphate, reduces ATP production, and consequently enhances thermogenesis.

So the correct option is 'Thermogenin'.

Multiple choice bio-chemistry biological oxidation oxidative phosphorylation living organisms and energy production glycolysis

Identify the wrong statement.

  1. Proton motive force drives the uniport.
  2. Movement of NO$ _3$ ions in cotransport is against their own concentration gradient.

  3. Azides inhibit the process of respiration.

  4. ATPase serves as proton-translocating carrier protein.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Proton motive force drives ATP synthesis via ATP synthase, not uniport. The other statements describe known biological processes.

Multiple choice bio-chemistry biological oxidation oxidative phosphorylation living organisms and energy production glycolysis

In mechanism, photophosphorylation is very similar to

  1. substrate-level phosphorylation

  2. oxidative phosphorylation

  3. Calvin cycle

  4. glycolysis
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Oxidative phosphorylation is the process in which ATP is formed by the transfer of electrons from NADH or FADH 2 to O 2 by a series of electron carriers. The sunlight-driven production of ATP from ADP and inorganic phosphate is called photophosphorylation.

So, the correct option is, 'oxidative phosphorylation'.

Multiple choice bio-chemistry biological molecule lipids and their function some biomolecules lipids

Name the chemical formula.
C$ _{16}$H$ _{32}$O$ _2$

  1. Palmitic acid

  2. Stearic acid

  3. Glycerol

  4. Galactose
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Palmitic acid or hexadecanoic acid was discovered by Edmond Fremy. It is commonly found in plants, animals and microorganisms.Its chemical formula is CH$ _3$(CH$ _2$)$ _{14}$COOH.It is a saturated fatty acid.

Multiple choice bio-chemistry biological molecule lipids and their function some biomolecules lipids

Which of the following is not an essential unsaturated fatty acid


  1. Oleic acid

  2. Linoleic acid

  3. Linolenic acid

  4. Stearic acid
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Essential fatty acids are those that the body cannot synthesize. Linoleic and linolenic acids are essential. Oleic acid is non-essential. Stearic acid is a saturated fatty acid, not an unsaturated one.

Multiple choice bio-chemistry biological molecule lipids and their function some biomolecules lipids

What is a cholesterol?

  1. Phospholipid

  2. Wax

  3. Steroid

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

Steroids are crystallisable lipids having four hydrocarbon rings consisting of three cyclohexane and one cyclopentane ring and a long hydrocarbon side chain. Fatty acids are absent. In animals, sterols are precursors of steroid hormones and vitamin D. Cholesterol is a sterol of animal systems which forms bile salts, is a component of plasma membrane and hormones.