Lipids Flashcards Preview

A Level Biology: Topic 1 (Edexcel) > Lipids > Flashcards

Flashcards in Lipids Deck (19):
1

What are the functions of lipids?

Cell membranes
Energy store

2

What is the difference between lipids and carbohydrates?

Lipids have a lower proportion of oxygens and carbohydrates

3

What two types of organic chemicals make up fats and oils?

Fatty acids
Glycerol

4

What bonds link glycerol and fatty acids?

ester bonds

5

In what ways can fatty acids vary?

length of the carbon chain
Saturated or unsaturated

6

What makes a fatty acid unsaturated?

There are one or more double covelant bonds

7

What is a monoglyceride?

When a glycerol combines with one fatty acid in an ester bond

8

What is a diglyceride?

When a glycerol combines with two fatty acids in an ester bond

9

What is a triglyceride?

When a glycerol combines with three fatty acids in an ester bond

10

What is the process where an ester bond is formed?

Esterification

11

What reaction produces an ester bond?

Condensation reaction between the carboxyl group of the fatty acid and the hydroxyl group of the glycerol

12

What kind of acid is more likely to be solid at room tempreture?

Saturated fatty acid

13

Why is the hydrophobic nature of lipids important?

Waterproofing fur
Insulators
Allowing mammals to float easily
Don't change water potential of the cell

14

What is a phospholipid?

Where a phosphate group forms an ester bond with glycerol

15

What part of the phospholipid is hydrophobic?

The tail (fatty acids)

16

What part of the phospholipid is hydrophillic?

The head (glycerol and phosphate group)

17

What two structures can form if many phospholipids are put in water?

Monolayer/Bilayer
Micelles

18

How does a phospholipid monolayer form?

Between the air and water where the heads face the water and the tails face the air

19

How does a phospholipid bilayer form?

There is a water-based solution on each side with the heads pointing outwards and the tails pointing inwards