lipids

Lipids are made from…

c, h and smaller amounts of o

Examples of lipids:

fats, oils, cholesterol, steroids, waxes

Animals tend to produce…

fats, solid at room temp

Plants tend to produce…

oils, liquid at room temp

Lipids are big, so they're

insoluble, non polar, no charge, not attracted to water

What're lipids soluble in?

alcohol, macromolecules

Triglycerides are…

3 fatty acid chains joined to 1 glycerol by ester bonds, condensation, carboxyl and hydroxyl group involved

Functions of triglycerides:

energy source, store, insulator, buoyant, protection

Properties of triglycerides:

compact, high energy, insoluble, good shock absorbers

Triglyceride structure -> function link:
many… means lots of… when.. low.. good for…

many hydrogen atoms means lots of energy released when oxidised, low density good for buoyancy

Fatty acids can be saturated if…

carbon atoms bond to many hydrogen atoms

Fatty acids can be unsaturated if…

one or more fatty acid chains contain carbon atoms which form a double bond with another carbon

What does it mean if a double carbon bond is formed?

can't bond with as many hydrogens, forms a kink in the chain

Phospholipids are made up of…

1 glycerol, 2 fatty acids, 1 replaced by phosphate group, hydrophilic phosphate heads, hydrophobic fatty acid tails

How are phospholipids amphipathic?

they have both hydrophobic and hydrophilic parts

What do phospholipids form?

bilayers, making up cell membranes

Phospholipid structure -> function link:
Bilayer helps form…

bilayer helps form micelles, heads out, tails in, selectively permeable, amphipathic

Phospholipids can form balls called… structured with the…

micelles, heads outside, tails tucked in

Phospholipids are free to move, but wont move where tails are…

exposed to water, gives stability

Phospholipid bilayer is selectively permeable, so only…

small, non polar molecules can move thru tails, controls entry and exit

Cholesterol is made of… and is…

4 carbon rings, small, hydrophobic

Cholesterol is a… and helps…

a steroid alcohol, helps maintain fluidity of cell membranes,

What can cholesterol be used to make?

steroids, hormones like testosterone, oestrogen

Cholesterol structure -> function link:
small size…molecules sit in…parts in membrane. regulates…

small size, molecules sit in hydrophobic parts in membrane, regulates fluidity and stability