Lipids 3: cell membranes

Question 1

What are the 3 main types of membrane lipids and their functions

Answer 1

Phospholipids: build cell membranes
Glycolipids: involved in cell signalling
Cholesterol: increase fluidity of the membrane

Question 2

Compare the structure of the phospholipid to glycolipids

Answer 2

Phospholipids are made of 2 fatty acid tails attached to a glycerol or 1 attached to sphingosine platform + phosphate and alcohol group which determines specific properties.

Conversely: Glycolipids always use sphingosine platform, and in stead of the phosphoryl and alcohol group it just has a sugar.

Question 3

Where are sphingolipids/ ceramides found and what roles do they place

Answer 3

Found in plasma membranes of all eukaryotic cells. Highest conc in the CNS.
Participate in variety of cell signalling pathways regulating cell differentiation, proliferation and apoptosis.

Question 4

What are the two main components that make phosphatidate (precursor for phospholipids) and where do they come from.

Answer 4

Glycerol backbone and phosphate group (G3P) from gluconeogenesis and fatty acid chains from Fatty acid metabolism.