Asubstance that enters earth's cycles and does harm to living things is
a. hydrogen.
b. a pollutant.
c. freshwater.
d. oxygen.

Agene with the original sequence of atgtt—tact underwent substitution mutation to form atatt—tact after a few generations. tact is a part of a muscle protein encoding region, and atgtt codes for a digestive enzyme. what will be the effect of this mutation? a. the production of muscle protein will be affected. b. the production of digestive enzymes will be affected. c. the production of both the protein and the enzyme will be affected. d. the production of neither the protein nor the enzyme will be affected.

The cluster of developing cells from conception until birth is called an

What material did the moon come from?