Answer:
The answer is A they can act as agents of natural selection. Hope this helps.
Ill say B poor soil Because how would you grown vegetation with out good soil
Answer:
diploid
Explanation:
So humans have two homologous chromosome sets in each cell, meaning humans are diploid organisms.
Answer:
The gene for beta-galactosidase turns off.
Explanation:
The gene that codifies the beta-galactosidase enzyme is part of the <em>lac</em> operon, which also contains two other genes that produce enzymes involved in the metabolization of lactose.
Between glucose and lactose, the bacteria will preferentially use glucose as an energy source. On the other hand, lactose is a dimer, and thus a series of enzymes are needed to process lactose before its use as an energy source.
If there is no lactose present, the genes contained inside this operon are turned off (the operon is repressed).
