L2: The Molecules of Life

Question 1

List 4 monomers

Answer 1

Sugars, fatty acids, amino acids, nucleotides

Question 2

Polymer of sugars

Answer 2

Polysaccharides

Question 3

Polymer of fatty acids

Answer 3

Fats

Question 4

Polymer of amino acids

Answer 4

Protein

Question 5

Polymer of nucleic acids

Answer 5

Nucleotides

Question 6

General formula for monosaccharides

Answer 6

n(CH₂O)

Question 7

2 functional groups of monosaccharides

Answer 7

Carbonyl (C=O) & Hydroxyl (-OH)

Question 8

Difference between aldoses & ketoses

Answer 8

Aldoses contain a aldehyde group & ketoses contain a ketone group

Question 9

What is the most naturally occuring isomer?

Answer 9

D-isomers

Question 10

Is D-glucose or L-glucose recognised by enzymes?

Answer 10

D-glucose

Question 11

What are optical isomers?

Answer 11

2 compounds which contain the same number of atoms, and different spatial arrangements of atoms

Question 12

Which isomer has the hydroxyl group attached to the LEFT side of carbon?

Answer 12

L-isomer

Question 13

Which isomer has the hydroxyl group attached to the RIGHT side of carbon?

Answer 13

D-glucose

Question 14

What are epimers?

Answer 14

Stereoisomers that differ in configuration at a single asymmetric carbon

Question 15

How are complex carbohydrates formed?

Answer 15

By glycosidic bonds by a condensation reaction

Question 16

What are lipids?

Answer 16

Molecules in cells that are insoluble in water

Question 17

What are fatty acids?

Answer 17

Monomeric building blocks of triacylglycerols & glycerophospholipids

Question 18

What are aliphatic chains?

Answer 18

Straight chain made of only carbon & hydrogen bonds

Question 19

What effect does unsaturated fatty acids have on cell membranes?

Answer 19

Increase fluidity

Question 20

How are triacylglycerols formed?

Answer 20

Ester linkages between fatty acids & glycerol

Question 21

Structure of glycerophospholipids?

Answer 21

Glycerol backbone, but 1 fatty acid is replaced by a phosphate group

Question 22

What does it mean when glycerophospholipids are amphiphatic?

Answer 22

Have hydrophilic & hydrophobic regions

Question 23

Why are amphiphatic molecules important?

Answer 23

Forms biological membranes & micelles

Question 24

What are the non polar regions of a lipid?

Answer 24

Hydrophobic end

Question 25

What are the polar regions of a lipid?

Answer 25

Hydrophilic end

Question 26

Why is cholesterol important?

Answer 26

Necessary component for animal cell membranes

Question 27

Building blocks of RNA & DNA

Answer 27

Pentose sugar, nitrogenous base, phosphate

Question 28

What are the pyrimidines?

Answer 28

Cytosine, Thymine and Uracil

Question 29

What are the purines?

Answer 29

Adenine, Guanine

Question 30

What bonds are nucleotides joined together by?

Answer 30

Phosphodiester Bonds

Question 31

What bonds does ATP carry energy by?

Answer 31

Phosphoanhydride Bonds

Question 32

What does ‘polar’ mean?

Answer 32

A molecule where one end is slightly positive, and the other is slightly negative

Question 33

Are side chains involved in peptide bonding?

Answer 33

NO

Question 34

How is the folding of proteins determined?

Answer 34

Interactions of side chains

Question 35

Why is the shape of a protein important?

Answer 35

Determines its function

Question 36

Basic structure of a amino acid?

Answer 36

1. Carboxyl group
2. Amino group
3. Side chain