Cell Membrane Structures and Functions

Cell Membrane:

• The protective outer layer that controls what enters and leaves the cell.
  
• Stores information on DNA molecules / Directs and controls the activities of the cell.
  
• A folded membrane that moves materials around inside cells / Also acts as the site of manufacturing materials needed by the cell.
  
• The smallest organelle with a huge job / Makes proteins, which are the building blocks of the body.
  

What characteristic does the phospholipid bilayer have that allows smaller molecules to pass through the cell membrane.

• The phospholipid bilayer can easily move around (is fluid) allowing small molecules to pass through.

• The phospholipid bilayer can not easily move around (is static), therefore is can not allow any molecules to pass through.

• The phospholipid bilayer has the ability to open and close like a draw bridge.

• The phospholipid bilayer will only allow large particles to pass through.

Select ALL that describe the cell membrane.

• Selectively Permeable

• Fluid Mosaic

• Embedded Proteins

• Phospholipid Bilayer

These proteins are only found on the outside or inside surface of the cell membrane.

• Integral Proteins

• Peripheral Protein

• Glycoprotein

• Phosphate Protein

Hydrophobic region of the cell membrane?

• E
• B
• C
• A 

The sodium-potassium pumps requires energy to move ions across the cell membrane against their concentration gradient so it is a type of

• active transport
• osmosis
• diffusion
• facilitated diffusion

Which of the following functions as a recognition site for interactions between cells?

• Phospholipids
• Cholesterol 
• Fatty acids
• Glycolipids

What is the primary function of the plasma membrane?

• To produce food and energy for the cell.
• To protect the cell from it's surrounding.
• The cell using energy to move an amount of substances to another location where this substane is 
• Help transfer proteins to help the cell body to stay strong.

In biological membranes, the phospholipids are arranged in a _______, with the_______.

• bilayer; fatty acids pointing toward each other
• bilayer; fatty acids facing outward
• single layer; fatty acids facing the interior of the cell
• single layer; phosphorus-containing region facing the interior of the cell

The hydrophilic regions of a membrane protein are most likely

• present only in muscle cells
• associated with the fatty acid region of the lipids
• either on the surface or inserted into the interior of the membrane
• exposed on the surface of the membrane