Cell Biology

Question 1

Are phosphoglycerides polar or neutral?

Answer 1

Polar - contain both hydrophobic region (fatty acid tails) and hydrophilic region (phosphate head)

Question 2

How is the fluidity of cell membranes affected by temperature?

Answer 2

Higher temp = fluid
Lower temp = gel-like

Question 3

How do sessile organisms maintain membrane fluidity during low temperatures?

Answer 3

Altering lipid composition. Using a desaturase enzyme to increase proportion of unsaturated fatty acids. More C=C bonds creates more kinks in the lipid chains and thus higher fluidity.