Chapter 7 Quiz AP Bio

Which of the following statements correctly describes the normal tonicity conditions for typical plant and animal cells?

The animal cell is in an isotonic solution and the plant cell is in a hypotonic solution

After the system reaches equilibrium what changes are observed?

The water level is higher inside A than inside B

Which component is the fiber of the extracellular matrix?

A

Which component is cholesterol?

E

Which of the following statements is correct about diffusion?

It is a passive process in which molecules move from a region of higher concentration to a region of lower concentration

Which of the following membrane activities require energy from ATP hydrolysis

Na+ ions moving out of a mammalian cell bathed in physiological saline

Proton pumps are used in various ways by members of every domain of organisms: bacteria archaea, and eukarya. What does this most probably mean?

Proton gradients across a membrane were used by cells that were the common ancestor of all three domains of life

Cell membranes are asymmetrical. Which of the following is the most likely explanation?

The two sides of a cell membrane face different environments and carry out different functions

If you examine side A after three days you should find

a decrease in the concentration of NaCl and a decrease in the water level

A protein that spans the phospholipid bilayer one or more times is

a transmembrane protein

The movement of potassium into an animal cell requires?

an energy source such as ATP

Some regions of the plasma membrane called lipid rafts have a higher concentration of cholesterol molecules. As a result these lipid rafts

are more rigid than the surrounding membrane

Several epidemic microbial diseases of earlier centuries incurred high death rates because they resulted in severe dehydration due to vomiting and diarrhea. Today they are usually not fatal because we have developed which of the following?

hydrating drinks that include high concentrations of salts and glucose

Celery stalks that are immersed in fresh water for several hours become stiff and hard. Similar stalks left in a 0.15 M salt solution become limp and soft. From this we can deduce that the cells of the celery stalks are

hypertonic to fresh water but hypotonic to the salt solution

When a membrane if freeze-fractured the bilayer splits down the middle between the two layers of phospholipids. In an electron micrograph of a freeze-fractured membrane the bumps seen on the fractured surface of the membrane are

integral proteins

Water passes quickly through cell membranes because

it moves through aquaporins in the membrane

Which of the following processes includes all others?

passive transport

White blood cells engulf bacteria through what process?

phagocytosis

What kinds of molecules pass through a cell membrane most easily?

small and hydrophobic