Triglycerides and Phospholids

Question 1

What are triglycerides?

Answer 1

They are a type of lipid that are mainly used as energy storage molecules

Question 2

How are lipids formed?

Answer 2

By the condensation reaction of one molecule of glycerol and three molecules of fatty acid

Question 3

What are the monomers of lipids?

Answer 3

Glycerol and fatty acids

Question 4

What type of bonds are formed between glycerol and fatty acid chains?

Answer 4

Ester bonds

Question 5

What is released per ester bond?

Answer 5

One water molecule

Question 6

How many molecules of water are released per triglyceride formed?

Answer 6

3 molecules of water

Question 7

Do fatty acids have long or short ‘tails’?

Answer 7

They have long ‘tails’

Question 8

What are the tails of fatty acids made of?

Answer 8

A chain of hydrocarbons

Question 9

Are fatty acids saturated or unsaturated?

Answer 9

They can be either

Question 10

What is palmitate? Saturated or unsaturated?

Answer 10

Saturated

Question 11

Where is chemical energy stored in fatty acids?

Answer 11

The hydrocarbon tails

Question 12

How does chemical energy being stored in the hydrocarbon tails help?

Answer 12

Lots of energy can be released when triglycerides are broken down

Question 13

Why are triglycerides insoluble in water?

Answer 13

The fatty acid tails are hydrophobic

Question 14

Which part of a phospholipid is hydrophobic?

Answer 14

Fatty acid tails

Question 15

Why is it important that triglycerides repel water (are insoluble in water)?

Answer 15

Because if they didn’t repel water, the water would enter the cell through osmosis. This would make the cells swell up.

Question 16

Why do the insoluble triglycerides crowd together as droplets?

Answer 16

Because the hydrophobic fatty acid tails face inwards

Question 17

What are phospholipids?

Answer 17

A type of lipid that forms a bilayer

Question 18

What are phospholipids the main component of in cells and their responsibility?

Answer 18

They are the main component of cell membranes and are responsible for controlling what goes into and out of the cells

Question 19

How are phospholipids and triglycerides similar in structure?

Answer 19

They are both composed of fatty acid chains attached to glycerol

Question 20

What is the main difference in structure between phospholipids and triglycerides?

Answer 20

Instead of the 3 hydrophobic fatty acid tails like in the triglycerides the phospholipids have 2 and one hydrophilic phosphate group

Question 21

How many fatty acid chains do phospholipids have?

Answer 21

They have 2

Question 22

In membranes where do the hydrophobic fatty acids face?

Answer 22

Where there is no water

Question 23

Which part of the phospholipid is hydrophilic?

Answer 23

Phosphate head

Question 24

In membranes where does the hydrophilic phosphate group face?

Answer 24

Attracted towards the water

Question 25

What is the difference between saturated and unsaturated lipids?

Answer 25

Unsaturated lipids have double bonds whereas saturated do not

Question 26

What is a hydrocarbon chain?

Answer 26

It is a chain of carbon atoms bonded to each other and to hydrogen atoms formed by covalent bonds

Question 27

What are saturated lipids usually at room temperature?

Answer 27

Mainly animal fats / solid

Question 28

What is it called when a lipid has one double bond?

Answer 28

It is mono-unsaturated

Question 29

What is it called when a lipid has more than one double bond?

Answer 29

A polyunsaturated fat

Question 30

What do double bonds cause in a chain?

Answer 30

A kink

Question 31

What does the kink caused by double bonds prevent?

Answer 31

Chains packing too closely together

Question 32

What state are unsaturated lipids at room temp?

Answer 32

Liquids i.e. oils

Question 33

How do you get saturated fatty acids?

Answer 33

If there are only single bonds between carbon atoms in the hydrocarbon chain

Question 34

What type of bonds do carbon atoms have in saturated fatty acids?

Answer 34

Single

Question 35

What state are saturated fats at room temperature?

Answer 35

Solid

Question 36

Where do saturated fats usually originate from?

Answer 36

Animals

Question 37

What type of disease are linked to saturated fats in humans?

Answer 37

Cardiovascular disease

Question 38

Examples of foods with a high proportion of saturated fat are:

Answer 38

Cream, cheese, butter, other whole milk dairy products and fatty meals

Question 39

How do you get unsaturated fats?

Answer 39

When the hydrocarbon chain contains at least one double bond between carbon atoms, then it is unsaturated

Question 40

What is the main difference between saturated and unsaturated fatty acids?

Answer 40

Their hydrocarbon tails

Question 41

What is an example of unsaturated fatty acids?

Answer 41

Cooking oils

Question 42

What state are unsaturated fats at room temperature?

Answer 42

Liquid

Question 43

Why are unsaturated fatty acids liquid at room temperature?

Answer 43

Double bonds kink the carbon chain so unsaturated fats cannot pack together tightly

Question 44

What fat has double bonds in their hydrocarbon tail?

Answer 44

Unsaturated fats

Question 45

What type of atoms are saturated atoms ‘saturated’ with?

Answer 45

Hydrogen