Cell Membrane 3.3

Question 0

is a molecule composed of three basic parts:

Answer 0

phospholipid

Question 1

or the plasma membrane, forms a boundary between a cell and the outside environment and controls the passage of materials into and out of a cell

Answer 1

Cell membrane

Question 2

What are the 3 basic part of the phospholipid?

Answer 2

a charged phosphate group • glycerol
• two fatty acid chains

Question 3

which describes the arrangement of the molecules that make up a cell membrane

Answer 3

fluid mosaic model,

Question 4

which means it allows some, but not all, materials to cross.

Answer 4

selective permeability

Question 5

is a protein that detects a signal molecule and performs an action in response.

Answer 5

Receptor

Question 6

What are the two kinds of receptors?

Answer 6

Intracellular rector and membrane receptor

Question 7

A molecule may cross the cell membrane and bind to an intracellular receptor, as shown in Figure 3.3. Intracellular means “within, or inside, a cell.” Molecules that cross the membrane are generally nonpolar and may be relatively small.

Answer 7

Intracellular receptor

Question 8

A molecule that cannot cross the membrane may bind to a receptor in the cell membrane, as shown in Figure 3.4. The receptor then sends the message to the cell interior. Although the receptor binds to a signal molecule outside the cell, the entire receptor changes shape—even the part inside the cell.

Answer 8

Membrane receptor