Regents Biology

Lipids Concentrated energy molecules

Regents Biology 2003-2004

Lipids

§ Examples u fats u oils u waxes u steroids

w Cholesterol w Sex hormones

u  lipid soluble vitamins w Vitamin A, E, D, K

Regents Biology 2003-2004

Lipids

§  Function: u energy storage

§  very concentrated §  twice the energy as carbohydrates! §  broken down by lipases

u cushions organs u protects cells

§ Cell membranes are lipid u  insulates body

§  think whale blubber!

Regents Biology 2003-2004

Structure of Fat So much hydrogen and carbon together= hydrocarbons

Regents Biology 2003-2004

Saturated fats § Most animal fats

u solid at room temperature

§  Limit the amount in your diet u contributes to

heart disease u deposits in

arteries

Regents Biology 2003-2004

Unsaturated fats § Plant, vegetable & fish fats

u  liquid at room temperature §  the fat molecules

don’t stack tightly together

§ Better choice in your diet

Regents Biology 2003-2004

Saturated vs. unsaturated saturated unsaturated

ü

Regents Biology 2003-2004

Wax: waterproof and forms protective layers

u The shiny covering on leaves is called the cuticle that protects the leaf

u A Wax and oils on feathers

- wax repels water and helps to insulate

Regents Biology

Birds will dye if covered with petroleum oil because this oil tangles their feathers and prevents their natural oils from working. They are no longer insulated and die from the cold OR toxins in they ingest while trying to clean the oil off of themselves.

2003-2004

Regents Biology

If feather are not cleaned, the birds will die… After an oil spill in Australia, volunteers knitted penguin sweaters to prevent the birds from grooming themselves and swallowing toxic oil while waiting to be cleaned!

2003-2004

Regents Biology 2003-2004

Fats are critical for your cells! § Cell membranes are made out of fats.

u  phospholipids u  Phosphate containing hydrophillic heads are on

the outside touching water u  Fatty acid tails are hydrophobic and on the

inside away from water u  forms a barrier between the cell & the outside

Regents Biology

The cell membrane is a phospholipid bilayer. Bilayer because it has 2 layers of lipid sheets that create a barrier. .