lipids

Question 1

what do all lipids contain ?

Answer 1

hydrocarbons

Question 2

What reaction forms a triglyceride ?

Answer 2

A condensation reaction

Question 3

What type of molecule is a triglyceride

Answer 3

A lipid

Question 4

What are fatty acids tails made of ?

Answer 4

Hydrocarbons

Question 5

What is the structure of a triglyceride ?

Answer 5

1 glycerol attached to 3 fatty acids

Question 6

What are the tails of a triglycerides (in terms of water )?

Answer 6

Hydrophobic

Question 7

What do the tails do to aide triglycerides in their function ?

Answer 7

Tails make lipids insoluble in water

Question 8

Do fatty acids all have the same structure ?

Answer 8

They all have the same basic structure but the hydrocarbon tails varies

Question 9

What is the basic structure of a fatty acid ?

Answer 9

O =C-R
HO/
Carbon atom links fatty acid to glycerol
A variable R group hydrocarbon tail
Oxygen double bonded to carbon
Hydroxide single bonded to carbon
Carbon single bonded to Variable R group

Question 10

What happens in the reaction to form a triglycerides?

Answer 10

Condensation reaction .fatty acid joins to glycerol molecule by an ester bond .An molecule of water is released .
This happens 2x times more to form a triglyceride.

Question 11

What is the structure of glycerol

Answer 11

H
|
H-C-OH
|
H-C-OH
|
H-C-OH
|
H

Question 12

Where are phospholipids found ?

Answer 12

Found in cell membranes

Question 13

What is the structure of a phospholipid ?

Answer 13

One phosphate ,one glycerol and two fatty acid .
By etser bond

Question 14

Describe the structure of a phospholipid (including the properties )

Answer 14

Phosphate group is hydrophilic
Fatty acid tail is hydrophobic

Question 15

What the long hydrocarbon tail of fatty acids contain ?

Answer 15

Lots of chemical energy

Question 16

What happens to the energy when you break down a triglyceride ?

Answer 16

It gets released

Question 17

How much energy is released when a triglyceride is broken down ?

Answer 17

2x as much as carbohydrates

Question 18

What is one feature of a triglyceride?

Answer 18

It’s soluble

Question 19

Why is a triglyceride being soluble important with cells ?

Answer 19

Because it prevents it affecting the water potential of the cell because water entering the cell by osmosis would cause it to swell

It clumps together as insoluble droplets in cells so hydrophilic acid tails face inwards and SHEILD themselves from water using glycerol heads

Question 20

what is the difference between a saturated and unsaturated fatty acid ?

Answer 20

Saturated fatty acids don’t have any double bonds between their
carbon atoms. The fatty acid is ‘saturated’ with hydrogen.

Unsaturated fatty acids do have double bonds between
carbon atoms, which cause the chain to kink.

Question 21

describe the emulsion tests for lipids ?

Answer 21

Shake the test substance with ethanol for about a minute,
then pour the solution into water.
ƒ Any lipid will show up as a milky emulsion
ƒ The more lipid there is, the more noticeable the milky colour will be.