lipids

Question 1

4 uses of lipids

Answer 1

insulation (thermal and electrical)
energy source + store
protection
steroid hormones from cholesterol

Question 2

what steroid hormones from cholesterol are there

Answer 2

testosterone
oestrogen
progestrone

Question 3

how do elements in lipids compare to elements in carbs

Answer 3

the same except less oxygen

Question 4

describe the structure of a phospholipid

Answer 4

polar, hydrophilic head
hydrophobic tails

Question 5

define hydrophilic

Answer 5

attracted to water

Question 5

define hydrophobic

Answer 5

repels water

Question 6

monoglycaride

Answer 6

1 fatty acid + 1 glycerol molecule

Question 7

triglycaride

Answer 7

3 fatty acids + 1 glycerol molecule

Question 8

2 features of triglycerides

Answer 8

insoluble - hydrophobic tails
not polar - evenly distributed charges

Question 8

how is a triglyceride formed

Answer 8

glycerol + fatty acid in a condensation reaction forming 3 ester bonds

Question 9

when are fatty acids solid + examples

Answer 9

longer chain
animal fats butters

Question 10

when are fatty acids liquids + examples

Answer 10

shorter chain
contain doble c=c bonds
oils in plants
unsaturated

Question 11

can the R group of a fatty acid be saturated or unsaturated

Answer 11

both

Question 12

describe the structure, properties and examples of saturated fatty acids

Answer 12

Structure: Have no double bonds between carbon atoms in the R group, resulting in a straight chain.
Properties: Can pack closely together, leading to solid forms at room temperature (e.g., butter).
Examples: Commonly found in animal fats.

Question 13

describe structure, properties and examples of unsaturated fatty acids

Answer 13

Structure: Have one or more double bonds in the R group, causing a kink in the chain.
Properties: Cannot pack as closely together, resulting in liquid forms at room temperature (e.g., oils).
Examples: Found in plant oils and fish.

Question 14

difference between phospholipids and triglyceride

Answer 14

in phospholipids, one of the fatty acids of a triglyceride is substituted by a phosphate-containing group

Question 15

features of triglycerides

Answer 15

store energy
waterproofing
insulation
buoyancy

Question 16

what are triglycerides good at storing energy

Answer 16

many C-H bonds making them good for energy storage
releases a lo of energy when oxidised

Question 17

why are triglycerides good for waterproofing

Answer 17

hydrophobic nature
fatty acid chains are non-polar + repel water

Question 18

why are triglycerides good insulators

Answer 18

non polar - dont conduct electricity or heat well
= thermal and electrical insulation

Question 19

why are triglycerides good at being buoyant

Answer 19

low density helps animal s to float

Question 20

features of phospholipids

Answer 20

hydrophobic
bilayer
selective permeability

Question 21

why are phospholipids hydrophilic

Answer 21

water attracting phosphate heads
and hydrophobic fatty acid tails
forming phospholipid bilayer

Question 22

how is phospholipid bilayer selectively permeable

Answer 22

allowing certain molecules to pass while keeping others out