Suppose that a DNA segment has the following nucleotide sequence:
CTC–ATA–CGA–TTC–AAG–TTA.
Which nucleotide sequences would a complementary mRNA strand have?
(a) GAG–UAU–GAU–AAC–UUG–AAU
(b) GAG–TAT–GCT–AAG–TTC–AAT
(c) GAG–UAU–GCU–AAG–UUC–AAU
(d) GUG–UAU–GGA–UUG–AAC–GGU

Diffusion is important in body fluids, because it tends to

(a) Increase local concentration gradients

(b) Eliminate local concentration gradients

(c) Move substances against concentration gradients

(d) Create concentration gradients

How many amino acids are coded in the DNA segment:

CTC–ATA–CGA–TTC–AAG–TTA?

(a) 18

(b) 9

(c) 6

(d) 3

If a cell lacked ribosomes, it would not be able to

(a) Move

(b) Synthesize proteins

(c) Produce DNA

(d) Metabolize sugar

(e) Divide

When a cell is placed in a(n)___solution, the cell will lose water through osmosis. This process results in the___ of red blood cells

(a) hypotonic; crenation

(b) hypertonic; crenation

(c) isotonic; hemolysis

(d) hypotonic; hemolysis

The sodium–potassium exchange pump

(a) Is an example of facilitated diffusion

(b) Does not require the input of cellular energy in the form of ATP

(c) Moves the sodium and potassium ions along their concentration gradients

(d) Is composed of a carrier protein located in the plasma membrane

(e) Is not necessary for the maintenance of homeostasis

Microvilli are found

(a) Mostly in muscle cells

(b) On the inside of plasma membranes

(c) In large numbers on cells that secrete hormones

(d) In cells that are actively engaged in absorption

(e) Only on cells lining the reproductive tract