Question

Proteins are used for many structural functions such as in the actin and myosin in muscle or as a part of the cytoskeleton scaffolding that maintains cell shape. What other main function do proteins serve?
A.
as enzymes to control the rate of reactions and regulate cellular activity
B.
as waterproof membranes to regulate the transport of molecules in and out of the cell
C.
as coding for genotypic expression and phenotypic traits
D.
as cellulose to form the major structural component of plant cell walls

Answer 1

Answer:

A

Explanation:

Proteins are large biomolecules produced in living cells. They are polymers made up of monomeric units called amino acids. Asides being structural components as highlighted in the question, complex proteins produced in living cells also serves as biological catalysts that regulates biochemical reactions in the body of living organisms. The protein that perform this function of regulating reactions is called ENZYME.

Catalytic enzymes affects the rate of biochemical reactions, without them, reactions will occur slowly or not at all. Enzymes, which can be anabolic or catabolic depending on whether they catalyze building up or breaking down of complex molecules respectively, are usually specific about what (substrates) they act on.

The amino acids that make up specific enzymes are modified into a three-dimensional shape. This shape determines its function and confers upon it the ability to speed up a reaction. An enzyme gets its name from the type of reaction they catalyze e.g. cellulose synthase catalyzes the synthesis of cellulose from glucose.

Answer 2

Answer: (A) as enzymes to control the rate of reactions and regulate cellular activity.

Explanation: Proteins - control rate of reactions and regulate cell processes, form important cellular structures and transport substances into/out of cells or fight disease.