1. when a person does strenuous exercise, small blood vessels (capillaries) near the surface of the skin increase in diameter. this change allows the body to be cooled. which of the following best illustrates these statements?

1points
a
excretion

b
homeostasis

c
locomotion

d
synthesis

2. which two statements below correctly describe one similarity and one difference between cellular respiration and photosynthesis?

cellular respiration and photosynthesis both involve water.
cellular respiration uses sugar and photosynthesis produces sugar.
cellular respiration and photosynthesis both use light to produce energy.
cellular respiration requires light energy and photosynthesis requires chemical energy.
1points
a
statements 1 and 2

b
statements 1 and 4

c
statements 2 and 3

d
statements 3 and 4

3. materials are able to move across a cell membrane through one of two methods: active transport or passive transport. what is the difference between the two?

1points
a
active transport requires the cell to form vesicles, while passive transport requires the use of membrane pumps.

b
active transport requires the cell to expend energy, while passive transport does not.

c
active transport is the only form of transport that requires the use of protein carriers.

d
passive transport is the only form of transport that requires the use of protein carriers.

4. a trait in cows is determined by two alleles of a single gene: allele r is dominant, and allele r is recessive. what is the probability of the dominant trait being expressed in the offspring of a cross between one rr parent and one rr parent?

1points
a
25 percent

b
50 percent

c
75 percent

d
100 percent

5. overuse of antibiotics has caused antibiotic resistance in some bacteria in a population. which statement describes the most likely impact of natural selection on the bacterial population?

1points
a
beneficial mutations have decreased, resulting in a larger population than normal.

b
only the genes for antibiotic resistance are now expressed, eliminating other genes.

c
more antibiotic-resistant bacteria have survived, resulting in more offspring with this trait.

d
the bacteria have become genetically isolated, resulting in decreased reproductive rates.