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Flashcards in Lipids Deck (11):
1

Lipids

Group of substances soluble in alcohol but not water (because non-polar substance), smaller amounts of oxygen

2

Triglyceride is made of

Glycerol and 3 fatty acids

3

What does a C=C do?

Make unsaturated
Change shape of chain
Kink push molecules apart so more fluid so lower melting point

4

Carboxyl group

-COOH

5

Carboxyl ionises into

H+ and -COO-

6

Triglyceride functions

Energy source
energy store
Insulation
Buoyancy
Protection

7

Why are triglycerides good energy stores/sources?

Less oxygen atoms so higher proportion of hydrogen atoms so release more energy
Insoluble in water so doesn't affect water potential

8

Phospholipid structure/function

Same as triglyceride but 1 fatty acid replaced by phosphate group

Selectively permeable, let's small non-polar molecules through

9

Cholesterol properties

Small hydrophobic
Steroid alcohol

10

Cholesterol structure

4 carbon based rings,
Isoprene units
Not made from glycerol or fatty acids

11

Cholesterol is small and hydrophobic so…

Can pass through hydrophobic part of membrane
Sit in bilayer to regulate fluidity of membrane