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Which plasma membrane component can be either found on its surface or embedded in the membrane structure?

a. protein

b. cholesterol

c. carbohydrate

d. phospholipid

Which characteristic of a phospholipid contributes to the fluidity of the membrane?

1. its head
2. cholesterol
3. a saturated fatty acid tail
4. double bonds in the fatty acid tail

What is the primary function of carbohydrates attached to the exterior of cell membranes?

1. identification of the cell
2. flexibility of the membrane
3. strengthening the membrane
4. channels through membrane

A scientist compares the plasma membrane composition of an animal from the Mediterranean coast with one from the Mojave Desert. Which hypothesis is most likely to be correct?

1. The cells from the Mediterranean coast animal will have more fluid plasma membranes.
2. The cells from the Mojave Desert animal will have a higher cholesterol concentration in the plasma membranes.
3. The cells’ plasma membranes will be indistinguishable.
4. ‘The cells from the Mediterranean coast animal will have a higher glycoprotein content, while the cells from the Mojave Desert animal will have a higher lipoprotein content.

Water moves via osmosis_________.

1. throughout the cytoplasm
2. from an area with a high concentration of other solutes to a lower one
3. from an area with a high concentration of water to a one of lower concentration
4. from an area with a low concentration of water to higher concentration

The principal force driving movement in diffusion is the ________.

1. Temperature
2. Particle size
3. Concentration gradient
4. Membrane surface area