LIPIDS

Question 1

What are lipids?

Answer 1

Contain C,H,O

Macro molecules

Question 2

Are lipids polar?

Answer 2

Non polar- the electrons in outer orbitals forming bonds are distributed evenly , meaning they’re INSOLUBLE in water

Question 3

Functions of lipids?

Answer 3

Membrane formation and creation of hydrophobic barriers 
Hromone production 
Electrical insulation 
Waterproofing
Source of metabolic water

Question 4

Functions of Tricylerides

Answer 4

Thermal insulation
Mechanical insulation
Cushioning
buoyancy aid

Question 5

What are tricylcerides ?

Answer 5

Combining of 1 glycerol molecle and 3 fatty acids

Question 6

What is a glycerol and a fatty acid?

Answer 6

Glycerol- type of alchohol

Fatty acid- type of carboxylic acid that contains a carboxyl group with a hydrocarbon chain

Question 7

Saturated tricylcerides

Answer 7

No double bonds 
Each carbon atom within the chain has 2 hydrogens attatched 
Saturated with hydrogen 
HC backbone is straight 
Solid- fats

Question 8

Unsaturated triclycerides

Answer 8

1 or more double bonds
Carbon atoms only have 1 hydrogen atom attatched
Double bond results in a KINK in the backbone, menaing that they cannot pack as closely together- liquid at room temperature(oils)

Question 9

1 double bond in unsaturated tricylceride?

Answer 9

MONO unsaturated

Question 10

2 or more double bond in unstaturated tricylceride?

Answer 10

POLY unsaturated

Question 11

How is the glyerol and fatty acid joined in tricyclerides?

Answer 11

ESTER BOND

The hydroxyl groups interact with the Hydrogen on glycerol, forming 3 hydrogens and esterbonds

Question 12

What is esterification

Answer 12

Process of forming a ester bond, condensation reaction

Question 13

What are Phospholipids?

Answer 13

Modified tricylceride

Contain P,C,H and O

Question 14

Are phospholipids soluble in water

Answer 14

YES

The inorganic phospahte ion are negatively charged

Question 15

What is the phosphate vs fatty acid like in a phospholipid

Answer 15

Phosphate head is polar - HYDROPHILLIC

Fatty acid tail is NON polar- HYDROPHOBIC

Question 16

Phospholipid+ water?

Answer 16

Mono layer
Bilayer
Micelle

Question 17

What is a monolayer?

Answer 17

PHOSPHOLIPID HEADS dissolve in water and the tails point out of the water
Called surface active agents or surfacants

Question 18

What is a bilayer?

Answer 18

2 layered sheet

All the hydrophobic tails pointing towards teh centre of teh sheet, protected from the water by the hydrophillic heads

Question 19

Saturated phospholipids- phospholipid bilayer

Answer 19

No kink
Pack CLOSELY together and from hydrophobic interavtions between individual fatty acid tails
Membrane is less fluid and doesnt break apart so easily at higher temps

Question 20

Unsaturated phospholipid bilayer

Answer 20

KINK
Cant pack as closely together
Less energy required ti break bonds holding fatty acids together
Membrane remains flod at lower temeratures and breaks apart more easily at higher temperatures

Question 21

What are sterols?

Answer 21

Type of lipid
Complex alachohol molecule based on 4 carbon ring structure with a OH group at one end
Hydoxyl group - hydrophillic and polar, rest of moelcule is hydrophobic

Question 22

Are sterols narrow or thick?

Answer 22

NARROW, allowing them to fit between cell membranes

Question 23

Cholesterol

Answer 23

Type of sterol

Manufactured in liver and intestines

Question 24

Importance of cholesterol

Answer 24

Prevents leackage of ions through membranes(mylein sheath)
Regulates fluidity and strength in membrane and mechanical stablity, positioned between phospholipids with teh OH group at the periphery of the membrane
and ensures its not too fluid or solid