An enzyme is a protein
transports nutrients across a membrane
increases the rate of a chemical reaction
receives and sends signals across a cell
provides structure for the cell’s organelles

The given blank can be filled with that it increases the rate of a chemical reaction.

Explanation:

A substance or a component, which functions as a catalyst in the living species, monitoring the rate at which chemical reactions advances without itself getting changed in the entire process is known as an enzyme. The enzyme works by enhancing the rate of a chemical reaction. The biological procedures that take place inside the living species are the chemical reactions, and the majority of these are monitored by enzymes. In the absence of enzymes, several of these reactions would not occur at the desired rate.

the answers are as following:

1. c. double helix, nucleosome, coil, supercoil, chromosome

2. b. g2 phase, preparation for mitosis

3. d. interphase consists of the g1, s, and g2 phases

4. c. metaphase

5. a. chromosomes are duplicated before cell division so that each new daughter cell has a complete set