NEET Botany Biology Biomolecules MCQs

HMG-CoA reductase is the rate-limiting enzyme in cholesterol biosynthesis.

The process occurs primarily in the liver.

NADPH provides the reducing equivalents for the biosynthesis of cholesterol.

Oxygen is directly involved in the condensation of isoprene units to form squalene.

Partial double bond character

Planar structure

Free rotation around the C-N bond

Trans configuration

Repulsive forces between phosphate groups

Base stacking interactions

Free rotation around the phosphodiester bond

Electrostatic attraction between sugars

Hydrophobic interactions

Hydrogen bonds

Ionic interactions

Peptide bonds

Formation of extensive alpha-helices

Increased tendency to form beta-sheets

Disruption of regular secondary structure (e.g., alpha-helices and beta-sheets)

Enhanced protein stability at high temperatures

Feedback inhibition involves the end-product of a pathway inhibiting an earlier enzyme.

Allosteric regulation exclusively involves the binding of molecules to the active site of an enzyme.

Covalent modification, like phosphorylation, can alter enzyme activity.

Enzyme compartmentalization within organelles can regulate metabolic flux.

Catabolism and anabolism are independent processes with no interaction.

Anabolism provides the energy for catabolism.

Catabolism and anabolism utilize the same enzymes.

Catabolism provides the energy and building blocks for anabolism.

It decreases the $V_{max}$ without changing the $K_m$.

It increases the $K_m$ without changing the $V_{max}$.

It decreases both the $K_m$ and the $V_{max}$.

It increases both the $K_m$ and the $V_{max}$.

Acting as allosteric inhibitors

Stabilizing the enzyme's structure

Participating directly in the catalytic mechanism

Facilitating substrate binding

Energy storage

Structural support

Prevent water loss

Cellular communication