Physiology Module 1 (Section 2)

Membrane physiology functions (3)

1. ensures cell survival

2. maintains homeostasis

3. works with surrounding cells

Function of phospholipids

have polar heads (hydrophobic) and non-polar fatty acid tails (hydrophilic) that allow transfer of molecules and separation between environments.

What is the function of cholesterol

found between the phospholipids

prevents fatty acid chains from packing and makes the structure rigid.

keeps the membrane fluid

Membrane proteins structure and function

Embedded into the phospholipid membrane to maintain structure, transport and signalling.

Ion channels structure and function

Specialized membrane proteins that permit entry and exit of ions.

Carbohydrate chains structure and function

Attached to proteins or bilayer.

Forms glycoproteins and glycolipids

These stabilize the structure and help with transport

Cystic fibrosis and its impact on the plasma membrane

Defect in chloride ion channels resulting in uncontrolled amounts of fluid and mucus entering the lungs.

Alzheimer’s disease and its impact on the plasma membrane

Oxidative stress that causes the phospholipids to alternate and degrade over time.

What makes the membrane fluid?

Viscus bilayer where individual phospholipids can move.

What makes the membrane mosaic?

Embedded proteins and other molecules.

Ex: glycoproteins and glycolipids