Enzyme molecules react with reactants to produce substrates. true false

False.

Explanation:

Enzymes are proteins produced by all living organisms. They selectively accelerate chemical reactions as part of the essential process of life such as digestion, breathing, metabolism, and maintenance of tissues. Enzymes can increase the speed of a reaction by a factor of up to 10^17 times more than the uncatalyzed reaction. An enzyme combines with its substrate to form an enzyme-substrate complex as an essential step in enzymatic catalysis.

Substrate binding occurs only in a specific and small region of the enzyme. This region to which the substrate binds is called the ACTIVE CENTER or Active Site of the enzyme. A molecule to be accepted as a substrate must have the appropriate spatial shape to fit into the active center and chemical groups capable of establishing precise bonds with the active center radicals.

stimulus is a change in the environment that causes an organism to react. the response is the reaction to the stimulus. some examples of stimuli for zebras are drought, to many predators, and bad feeding grounds such as dead grass or plants. zebras respond to stimuli just like all other living organisms

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