Cell Membrane FA F24

What characteristic of phospholipids causes semipermeability of the cell membrane?

• They have hydrophobic tails and hydrophilic heads

• They are fully hydrophobic

• They are polar molecules

• They are fully hydrophillic

What is the cell membrane made of?

• Carbohydrates and Lipids only

• Lipids only

• Lipids, Proteins, and Carbohydrates

• Lipids and Proteins only

In the phospholipid bilayer, which region is hydrophilic?

• A Only

• B Only

• Both A and B

• Neither A or B

Part A of the cell membrane is composed of which of the following?

• Both the heads and the tails of the phospholipid molecules, arranged randomly

• Proteins attached to the heads of the phospholipid molecules

• The hydrophilic heads of the phospholipid molecules

• The hydrophobic tails of the phospholipid molecules

What best describes region B in the pictured phospholipid bilayer?

• Nonpolar

• Hydrophobic

• Amphipathic

• Hydrophilic

Which of the following is true of the structures labeled A in the Cell Membrane?

• They are membrane proteins

• They are phospholipids

• They are carbohydrates

• They are entirely hydrophobic

Which of the following is true of the structures labeled D in the Cell Membrane?

• They are membrane proteins

• They are hydrophilic

• They are carbohydrates

• They are hydrophobic

Which of the following is true of the structures labeled C in the Cell Membrane?

• They are nonpolar

• They are hydrophilic

• They are carbohydrates

• They are hydrophobic

The cell membrane is made up of several components, each with their own function. The main part is the ​ (a)   , which allows small or non-polar molecules (such as ​ (b)   or steroid hormones) to pass through the membrane. Larger and polar molecules (such as ​ (c)   and sugars) are too big to pass through the phospholipid bilayers so they use the ​ (d)   to travel in or out of the cell. ​ (e)   helps make the cell membrane more rigid or loose to control what goes in and out of the cell.

• phospholipid bilayer
• oxygen gas
• water
• channel or transport proteins
• Cholesterol
• Carbohydrate
• Glycerol
• fatty acids

True or False: Oxygen and carbon dioxide can pass through the cell membrane easily.

• True

• False