Exam 5: Lifes Border: The Plasma Membrane

Amino acids move into the cell via facilitated diffusion. Knowing this, you also know that:

For substances to move passively through the cell membrane, there must be:

Endocytosis:

Which of the following is the function of cholesterol in the cell membrane?

Recognition substances in the plasma membrane are composed of integral proteins.

Yeast cells take up glucose (a sugar) to use as their primary source of energy. Typically, glucose concentrations outside yeast cells are far lower than glucose concentrations inside the cells. Therefore, for yeast to take up glucose, they must:

A phospholipid has ________ fatty acids attached to it.

The "backbone of the plasma membrane is the phospholipid bilayer.

It seems that bacteria and molds should grow well in jam. It's extremely high in sugar, a substance cells typically use for energy, and contains enough other nutrients to support cell growth. Yet jam can be left unrefrigerated for a very long time without contamination by microorganisms. How can this be?

The cytoskeleton is attached to cholesterol.

The 1985 Nobel Prize in Physiology or Medicine was awarded to Michael Brown and Joseph Goldstein for their work on cholesterol metabolism. Brown and Goldstein investigated the cause of remarkably high levels of circulating cholesterol found in certain families. Just as remarkable was the high incidence of heart disease in these families. What they found was not what might be expected-these individuals did not make too much cholesterol. Instead, most of these people had defects in receptor-mediated endocytosis (RME). What could possibly link high cholesterol levels in the blood and defective RME in these patients?

The area of the cell membrane where two layers of fatty acid tails face each other is called the:

You have isolated a cell that is unable to produce cholesterol for its cell membranes. Which of the following defects is this cell most likely to have?