Carbohydrates and Lipids

Question 1

What do all macromolecules contain?

Answer 1

Carbon

Question 2

What is the function of Nucleic acids (DNA & RNA)?

Answer 2

Information storage and transmission

Question 3

List 6 functions of proteins.

Answer 3

1. Enzymatic catalysis
2. Antibodies
3. Hormonal signalling
4. Structural proteins
5. Contractile proteins
6. Gas transport

Question 4

What is the function of carbohydrates?

Answer 4

Energy source

Question 5

List 3 functions of lipids (fats)?

Answer 5

1. Energy source
2. Membrane components
3. Hormonal signalling

Question 6

What is the general molecular formula of carbohydrates?

Answer 6

[C(H2O)] n

Question 7

Carbohydrates are classified according to what?

Answer 7

The number of monomers.

Question 8

List 4 forms of carbohydrates and how many monomeric units they contain.

Answer 8

1. Monosaccharides (1 monomeric unit)
2. Disaccharides (2 monomeric units)
3. Oligosaccharides (3-10 monomeric units)
4. Polysaccharides (>10 monomeric units)

Question 9

What are isomers?

Answer 9

Compounds which contain the same atoms but are bonded to form different 3D arrangements.

Question 10

Give 2 isomers of glucose. How many carbon atoms do these contain?

Answer 10

Fructose and Galactose. All contain 6 carbon atoms.

Question 11

When a disaccharide is formed, what is eliminated and what kind of bond is formed?

Answer 11

Water is eliminated. A glycosidic bond is formed.

Question 12

Which 2 monosaccharides join together to form sucrose?

Answer 12

Glucose and fructose.

Question 13

Which 2 monosaccharides join together to form lactose?

Answer 13

Glucose and galactose.

Question 14

Which 2 monosaccharides join together to form maltose?

Answer 14

Glucose and glucose.

Question 15

What are the components of starch?

Answer 15

75% amylopectin
25% amylose

Question 16

What kind of polymer of glucose is amylopectin and what kind of glycosidic bonds form it?

Answer 16

Branched chain polymer of glucose.

Formed by a-1,4 and a-1,6 glycosidic bonds.

Question 17

What kind of polymer of glucose is amylose and what kind of glycosidic bonds form it?

Answer 17

Linear polymer of glucose.

Formed by a-1,4 glycosidic bonds only.

Question 18

Where is cellulose obtained from and what kind of polymer of glucose is it?

Answer 18

Plant sources.

Linear polymer of glucose.

Question 19

Where is glycogen obtained from and what kind of polymer of glucose is it?

Answer 19

Animal sources.

Extensively branched polymer of glucose.

Question 20

What is dextrin and what kind of oligomer of glucose is it?

Answer 20

The breakdown of starch and glycogen.

Branched oligomer of glucose.

Question 21

What are the 4 main types of important lipids?

Answer 21

1. Fatty acids
2. Triglycerides
3. Cholesterol
4. Cholesterol esters

Question 22

Unsaturated fatty acids have at least one what?

Answer 22

C=C double bond.

Question 23

What 2 things are joined together to form triglycerides?

Answer 23

Fatty acids and glycerol.

Question 24

What are ketone bodies?

Answer 24

Small (4-carbon), water-soluble fatty acids formed by the liver during fasting, when they become important energy substrates for the brain.

Question 25

What are the 3 main ketone bodies?

Answer 25

1. Acetoacetic acid 2. B-hydroxybutyric acid 3. Acetone

Question 26

Which type of reaction allows energy to be released from organic molecules?

Answer 26

Oxidation reactions.

Question 27

What is oxidation?

Answer 27

The loss of electrons.

Question 28

How are lipids transported through aqueous environments?

Answer 28

As lipoproteins.

Question 29

What does the hydrophobic core of lipoproteins contain?

Answer 29

Triglycerides and cholesterol esters.

Question 30

What does the hydrophilic surface of lipoproteins contain?

Answer 30

Phospholipids, free cholesterol, and apolipoproteins.

Question 31

List the lipoproteins from least to most dense.

Answer 31

1. Chylomicrons 2. VLDLs 3. LDLs 4. HDLs

Question 32

What is the main function of chylomicrons?

Answer 32

To deliver dietary (exogenous) TAG to the peripheral tissues.

Question 33

What is the main function of VLDLs?

Answer 33

To deliver endogenous TAG to the peripheral tissues.

Question 34

What is the main function of LDLs?

Answer 34

To deliver cholesterol to the peripheral tissues and liver.

Question 35

What is the main function of HDLs?

Answer 35

To deliver cholesterol from the peripheral tissues to the liver for elimination.