Lipids (Biochemistry) Flashcards
What are lipids?
fats, oils and waxes
What elements do they contain?
CArbon, Hydrogen and oxygen
Compare oxygen count in carbs to lipids
oxygen content is much lower than in carbohydrates
What is the polarity of lipids?
non-polar
What is the solubility of lipids?
insoluble in water, soluble in organic solvents (acetone and ether (also non polar)
What are the roles of lipids?
Thermal insulation
Energy Store
Buoyancy
Protection
Waterproofing
reducing water loss
source of metabolic water
Why do lipids provide thermal insulation?
fat tissue has fewer capillaries
How much energy per 1g is stored by lipids?
34KJ energy per 1g
Why does fat provide buoyancy?
it is less dense than either muscle or bone
how does fat provide protection?
fat can absorb shocks/impacts, protects organs against physical damage
Why is lipids good for waterproofing?
lipid is hydrophobic so repels water
How does lipid reduce water loss?
prevents desiccation/ drying out
Why are lipids a source of metabolic water?
3 water molecules given off per one triglyceride formed
How does an elephant seal use lipids?
as thermal insulation, buoyancy and a food store
How does a dormouse use lipids?
energy store for hibernation
how do seeds use lipids?
energy sore for germination/growth
how do kidneys use lipids?
protection against physical damage