Cell Membrane Structure and Function

Define cell (plasma) membrane

• lipid that helps minimize effects of temperature

• only on the outer surface of the plasma membrane and are attached to proteins or lipids; form distinctive cellular markers

• flexible boundary of a cell that separates a cell from its surroundings

• may extend partway into the plasma membrane, cross the membrane entirely, or be loosely attached to its inside or outside face

Tags

NGSS.MS-LS1-2

Which type of biological macromolecule is the main component of the plasma membrane?

• carbohydrate

• lipid

• protein

• nucleic acid

This image is an example of a phospholipid. Which part of a phospholipid is HYDROPHOBIC?

• the phosphate "head"

• the lipid "tails"

Tags

NGSS.MS-PS1-1

This image is an example of a phospholipid. Which part of a phospholipid is HYDROPHILIC?

• the phosphate "head"

• the lipid "tails"

Tags

NGSS.MS-LS1-2

NGSS.MS-PS1-1

What does "polar" mean?

• A molecule is cold

• A molecule has areas of positive and negative charge

Tags

NGSS.MS-PS1-1

What is a bilayer?

• A layer of solute molecules

• A layer of solvent molecules

• A double layer of phospholipids

• A single layer of phospholipids

Answer explanation

A bilayer is a double layer of phospholipids.

What does it mean for the cell membrane to be semi-permeable?

• It allows some materials (not all) to pass through.

• It prevents any material from entering or leaving the cell.

• It allows only water to pass through.

• It allows all materials to pass through.

Answer explanation

The cell membrane is semi-permeable, allowing some materials (not all) to pass through.

Tags

NGSS.MS-LS1-2

What is the function of the phospholipid bilayer of the cell membrane?

• allows large molecules to pass through the cell membrane

• allows small, non-polar molecules to pass through the cell membrane

• identifies the cell and allow for cell-to-cell communication

• stabilizes the fluidity of the cell membrane

What is the function of the transport and channel proteins of the cell membrane?

• allows large molecules to pass through the cell membrane

• allows small, non-polar molecules to pass through the cell membrane

• identifies the cell and allow for cell-to-cell communication

• stabilizes the fluidity of the cell membrane

What is diffusion?

• when molecules move 
• when molecules move from a high concentration to a low.
• no movement 
• molecules move everywhere

Tags

NGSS.MS-PS1-4