unit 1, lipids

Question 1

what makes up glycerol

Answer 1

3 carbons, 8 hydrogens, 3 oxygens

Question 2

what’s the difference between hydrophilic and hydrophobic

Answer 2

hydrophilic attracts water and hydrophobic repels water

Question 3

what makes up triglycerides

Answer 3

1 gylcerol molecule, 3 fatty acids

Question 4

what is the bond in triglycerides

Answer 4

it is an ester bond , formed by a condensation reaction by the three OH groups on the glycerol and the OH group of each fatty acid

Question 5

what is the diagram of a triglyceride?

Answer 5

the branches of the fatty acids attached to one glycerol molecule

Question 6

what are the properties of triglycerides

Answer 6

-the fatty acids are hydrophobic making it insoluble. The tails face inwards and the glycerol heads shield them from the water.
-They can be either saturated or unsaturated
-the hydrogen to oxygen ratio is larger so can release water
-high ratio of energy storage that weighs little which is good as it reduces mass animals have to carry around

Question 7

what makes up a phospholipid

Answer 7

1 glycerol molecule , 1 phosphate group, 2 fatty acid chains

Question 8

what is the bond in phospholipids

Answer 8

it is an ester bond formed by a condensation reaction between two OH groups of the glycerol and the OH group of each fatty acid chain

Question 9

what is the diagram of a phospholipid

Answer 9

2 branches of the fatty acids , 1 head of glycerol , inside the glycerols there is 1 phosphate

Question 10

what are the properties of phospholipids

Answer 10

the phosphate is hydrophilic and the fatty acid is hydrophobic, this forms a bilayer which makes up membranes around the cell

Question 11

example of phospholipids

Answer 11

hormones , eg) testosterone

Question 12

example of a triglyceride

Answer 12

energy store

Question 13

what’s the difference between saturated and unsaturated fatty acids

Answer 13

• saturated don’t have double bonds between their carbons , unsaturated do
•in unsaturated the chain bends or kinks due to the double bond
•saturated can contain many double carbon bonds

Question 14

how is phospholipids bilayer formed

Answer 14

the phosphate heads are hydrophilic and their fatty acid tails are hydrophobic, therefore forming a double layer with the heads facing outwards

Question 15

how is the barrier formed in the phospholipid bilayer

Answer 15

the centre of the bilayer is hydrophobic therefore water substances cannot easily pass through, this forms a barrier and separates the solution and creates different conditions on either side of the membrane

Question 16

what are the roles of lipids

Answer 16

Source of energy, waterproofing, insulation, protection

Question 17

how many water molecules are needed when breaking down triglyceride

Answer 17

3 , due to the three water molecules needed to attach the three fatty acids to the glycerol