Lipids

Question 1

Lipids are made from

Answer 1

A variety of different components but they all contain hydrocarbons

Question 2

The components lipids are made from relates to

Answer 2

The lipid’s function

Question 3

Triglycerides have

Answer 3

One molecule of glycerol with three fatty acids attached to it

Question 4

Fatty acids have long tails made of

Answer 4

Hydrocarbons

Question 5

Are fatty acid tails hydrophobic or hydrophillic

Answer 5

Hydrophobic

Question 6

What makes lipids insoluble in water

Answer 6

Fatty acid tails

Question 7

There are two kinds of fatty acid tails

Answer 7

Unsaturated and saturated

Question 8

Saturated fatty acids don’t have any

Answer 8

Double bonds between their carbon atoms, the fatty acid is saturated with hydrogen

Question 9

Unsaturated fatty acids have

Answer 9

Double bonds between carbon atoms, which cause the chains to kink

Question 10

Triglycerides are formed by

Answer 10

Condensation reactions

Question 11

In a triglyceride where does an ester bond form

Answer 11

Between the glycerol molecule and a fatty acid molecule

Question 12

Lipids found in cell membranes are called

Answer 12

Phospholipids

Question 13

A phospholipid has

Answer 13

a glycerol molecule, 2 fatty acids and a phosphate group

Question 14

The phosphate group in phospholipids is hydrophobic or hydrophilic

Answer 14

Hydrophilic

Question 15

Triglycerides are mainly used as

Answer 15

Energy storage molecules

Question 16

Why are triglycerides a good energy storage molecule

Answer 16

Due to the long hydrocarbon tails containing lot’s of chemical energy

Question 17

Triglycerides are a good storage molecule due to the fact they’re insoluble in water which means

Answer 17

That they don’t affect the water potential of the cell and cause water to enter the cells by osmosis which would make them swell

Question 18

The triglycerides bundle together as insoluble droplets in cells because

Answer 18

he fatty acid tails are hydrophobic, the tails face inwards shielding themselves from water with their glycerol heads

Question 19

Phospholipids make up the

Answer 19

Bilayer of cell membranes

Question 20

Phospholipids form a double layer due to

Answer 20

Their heads facing out towards the water on either side and the centre of the bilayer is hydrophobic

Question 21

Why is the centre of phospholipid bilayer hydrophobic

Answer 21

So water soluble substances can’t pass through easily

Question 22

What test is used for lipids

Answer 22

The emulsion test

Question 23

What is added to the sample during the emulsion test

Answer 23

Ethanol

Question 24

What is the positive result for lipids

Answer 24

A milky emulsion, the stronger the sample the milkier the colour