Pack 3 - Transport Across Membranes

Question 1

Explain the arrangement of phospholipids in the cell surface membrane

Answer 1

Hydrophobic tails repel water and hydrophilic heads attraced to water
It’s a bilayer

Question 2

What is the role of the disulfide bridge in forming the quaternary structure of an antibody

Answer 2

Joins 2 polypeptide chains

Question 3

Co transport

Answer 3

Carrier protein = protein has specific shape/ tertiary structure binds to ion which changes shape and allows substances to pass across membrane

Active transport = use ATP to go against concentration gradient using carrier protein

Question 4

Cell surface membrane adapted

Answer 4

Have lots of rote in carried and protein channels embedded in their membrane
Folded to to have micro villi to increase SA