The Student Room Group
You could start with it's structure and the atoms included...
Reply 2
yes i understand about the structure and atoms but i need to talk mainly about

1) energy store 2) protection 3) buoyancy 4)thermal insulation 5) waterproofing

this essay is to do with the functions mainly.
Reply 3
i would have thought thats pretty simple.

lipids = fats = energy store
build up of fats = dampener
whales use fat as buoyancy and insulation (large people float more)
and i cant be bothered to explain the last bit as that needs a bit of work, but its god damn easy.
Reply 4
yes i know its simple. but i can't find no information.

i looked in textbooks. there isn't enough information to write 2 A4 sides
Lipids are high energy molecules, which can release twice as much energy as an equal mass of carbohydrates, by oxidation.
The lipids are stored as oils in many seeds (sunflower, groundnut) and fruits (palm, olive).
In animals they are stored as fats in adipose tissue, below the skin and around vital organs. These can be used in respiration, when carbohydrates are scarce/during starvation/dieting.

Since lipids are insoluble in water they serve the purpose of water proofing. Waxes are specially useful for this purpose.
Examples;
Waxy cuticle on leaves reduces evaporation,
Sebum from sebaceous glands of skin in mammals makes skin waterproof,
Oils in feathers of aquatic birds, etc.

Fats/adipose tissue is present around vital organs like liver and kidneys act as shock absorbers, preventing physical damage to these organs.

Adipose tissue below the skin is a good thermal insulator. This helps to preserve body heat and reduce heat loss. This is very useful to organisms living in very cold climate, ( Example: polar bears, walruses ).
The fats can also be used to provide energy when food is scarce.

Buoyancy: fats are less dense than water. This enables large aquatic mammals, like whales, seals, etc. to float on water

Perhaps you could expand on these points a little :smile:
Reply 6
yeh i will have to expand on these points. but i got a lot of expanding to do.

regards
Reply 7
also have a look at this
Reply 8
i guess that the site has ok explanations but most explanations i have found are all failer short. and its becoming hard for me to expand on them.

but i will do futher research maybe into how some animals manage to float because of buoyancy. and how lipids are found in cells. how the waxy cuticle is waterproofed by lipids. similarily how ducks have oil spread over their feature so they don't soak water up.

i got alot of writing to do. :rolleyes: