Lipids

Question 1

What is the function of lipids?

Answer 1

Cell membranes

Energy storage

Question 2

What are the differentiations of lipids?

Answer 2

Fats and oils

Question 3

What are lipids made up of?

Answer 3

Fatty acids and glycerol

Question 4

What is the bond between lipids?

Answer 4

Ester bonds is

Question 5

What is the characteristic functional group at the end of a lipid molecule?

Answer 5

Carboxyl group (-COOH)

Question 6

What is the displayed formula of glycerol?

Answer 6

H          
              I           
H    -     C   -     OH 
              I            
H    -     C   -     OH
              I
H    -     C   -     OH 
              I
             H

Question 7

How can fatty acid chains differ?

Answer 7

Length of carbon chain

May be saturated or unsaturated

Question 8

What is a saturated fatty acid?

Answer 8

Only contains single covalent bonds (C-C)

Question 9

Give an example of a saturated fatty acid.

Answer 9

Stearic acid

Question 10

What is an unsaturated fatty acid?

Answer 10

The carbon chains have one or more double bonds (C=C)

Question 11

Give an example of a polyunsaturated fatty acid.

Answer 11

Linoleic acid

Question 12

How is the ester bond formed between fatty acids?

Answer 12

Condensation reaction

Question 13

Where does the condensation reaction occur (functional groups) between fatty acids?

Answer 13

• COOH (fatty acid)

- OH (glycerol)

Question 14

What is the name of the condensation reaction?

Answer 14

Esterification

Question 15

What is the chemical composition of lipid molecules?

Answer 15

Many C-H bonds

Little O

Question 16

What happens to lipids in respiration?

Answer 16

They are oxidised

Question 17

What happens as a result of lipid oxidation?

Answer 17

Bonds are broken

CO2 and H2O are ultimate products

Question 18

What is the function of oxidising lipids in respiration?

Answer 18

Used to drive the production of ATP

Question 19

What is the nature of lipids?

Answer 19

Hydrophobic

Question 20

What is the importance of lipids for organisms?

Answer 20

Oils waterproof fur and feathers of mammals and birds
Insects and plants use waxing for waterproofing outer surface
Good insulators
Low density - helps mammals float
Dissolve in organic solvents
Insoluble in water - don’t affect water based reactions in cells

Question 21

What is present in the cytoplasm of every cell?

Answer 21

Inorganic phosphate ions

Question 22

How is a phospholipid formed?

Answer 22

Esterification between phosphate group and hydroxyl group of glycerol

Question 23

What are the properties of fatty acid chains in a phospholipid?

Answer 23

Neutral

Insoluble in water

Question 24

What charge does the phosphate group of a phospholipid hold?

Answer 24

Small negative charge

Polar - hydrophilic

Question 25

Which part of the phospholipid is hydrophilic?

Answer 25

Phosphate head

Question 26

Which part of the phospholipid is hydrophobic?

Answer 26

Fatty acid tail

Question 27

What do phospholipids form in water?

Answer 27

A no player (heads in water tails away from water) | Micelles (head points outward, tail points inwards)

Question 28

What is the structure of phospholipids in a cell membrane?

Answer 28

Bilayer

Question 29

What is the definition of a fatty acid?

Answer 29

An organic acid with a long hydrocarbon tail

Question 30

What is the chemical name of glycerol?

Answer 30

Propane - 1,2,3 - triol

Question 31

What is the definition of a monounsaturated fatty acid?

Answer 31

A fatty acid with only one double bond between C atoms

Question 32

What is a unit membrane?

Answer 32

A bilayer structure formed by phospholipids in an aqueous environment

Question 33

What is a hydrophobic molecule?

Answer 33

A molecule which will not dissolve in water

Question 34

What is a hydrophilic molecule?

Answer 34

A molecule which will dissolve readily in water

Question 35

What is a micelle?

Answer 35

A spherical aggregate of molecules in water with hydrophobic areas in the middle and hydrophilic areas outside