Membrane Structure Part One: Six Functions Of Membrane Proteins

Question 1

The plasma membrane

Answer 1

Boundary that separates living cell from surroundings
Semi permeable
Lipids and proteins

Question 2

Cellular membrane consists of

Answer 2

Lipids and proteins!
>Phospholipids are
The most abundant lipid in plasma membrane
Contain hydrophilic and hydrophobic regions - phospho lipid bilayer

Question 3

Fluidity of membranes

Answer 3

Phospholipids can move within the bilayer

Membrane proteins are dispersed and individually inserted into the phospholipid bilayer

Question 4

A cell membrane

Answer 4

A cell membrane is a collage of different proteins embedded in the fluid matrix of the lipid bilayer

Question 5

Six major functions of membrane proteins

Answer 5

Attachment to the cytoskeleton and extracellular matrix
Intercellular joining
Signal transduction
Enzymatic activity
Cell-cell recognition
Transport

Question 6

1. Attachment to cytoskeleton and extracellular matrix

Answer 6

Maintains cell shape and stabilizes cytoskeleton

Question 7

2. Intercellular joining

Answer 7

Proteins on adjacent cells hook together, briefly, for cell interaction/sharing

Question 8

3. Signal transduction

Answer 8

Transmission of molecular signals from a cell’s exterior to its interior

Question 9

4. Enzymatic activity

Answer 9

When a protein built into the membrane may be an enzyme with its active site exposed to substances in the adjacent solution

Question 10

5. Cell-cell recognition

Answer 10

Cell’s ability to distinguish one type of cell from another
When some glycoproteins (proteins bonded to short chains of sugars) serve as identification tags that are specifically recognized by other cells

Question 11

6. Transport

Answer 11

Transport proteins are used in various ways to move substances back and forth across the cell membrane