The profusion of skin colors and physical characteristics of different humans is due to .
a. the development of pure races
b. the differences in climate and other living conditions humans encountered as they populated the globe
c. biology rather than evolution
d. the emergence of dominant groups in the last three centuries

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.

answers are:

lysogenic     viral dna merges with host cell dna

lysogenic     no symptoms

lytic               viral dna takes over

lysogenic     virus does not destroy host cell

lytic               virus destroys host cell

lytic               induces symptoms of viral infection

lysogenic       cell reproduces and spreads provirus

. ph changes the ability of them he enzyme to dissolve in water.