biological molecules

Question 1

What is a hydrolysis reaction?

Answer 1

a reaction that breaks a chemical bond between 2 molecules and involves the use of a water molecules

Question 2

What is a condensation reaction?

Answer 2

a reaction that joins two molecules together with the formation of a chemical bond and involves the elimination of a molecule of water

Question 3

Examples of disaccharides

Answer 3

• maltose
• lactose
• sucrose

Question 4

Examples of polysaccharides

Answer 4

• cellulose
• starch
• glycogen

Question 5

Examples of monosaccharides

Answer 5

• glucose
• fructose
• galactose

Question 6

What are monomers?

Answer 6

small units which combine to make large chains (polymers)

Question 7

Examples of monomers

Answer 7

• monosaccharides
• nucleotides
• amino acids

Question 8

What are polymers?

Answer 8

long chains of monomers

Question 9

Examples of polymers

Answer 9

• DNA
• starch
• proteins

Question 10

What are the two major classes of lipids?

Answer 10

triglycerides and phospholipids

Question 11

What are the components of triglycerides?

Answer 11

• 3 fatty acids
• glycerol

Question 12

What are the components of a phospholipid?

Answer 12

• 2 fatty acids
• glycerol
• phosphate group

Question 13

What are the uses/functions of lipids?

Answer 13

• protection
• insulation
• plasma membrane
• waterproofing
• storage of energy

Question 14

Which part of a phospholipid is polar and hydrophilic?

Answer 14

the phosphate group

Question 15

Which part of a triglyceride is non-polar and hydrophobic?

Answer 15

the whole molecule is non-polar and hydrophobic

Question 16

Which part of a phospholipid is non-polar and hydrophobic?

Answer 16

the fatty acids

Question 17

What type of bond joins the glycerol and fatty acids?

Answer 17

ester bond

Question 18

What is the test and results for lipids?

Answer 18

ethanol & distilled water
cloudy-white

Question 19

Describe the tests for lipids

Answer 19

1. take dry and grease-free test tube
2. to 2cm^3 of sample being tested, add 5cm^3 of ethanol
3. shake thoroughly to dissolve and lipids present in the sample
4. add 5cm^3 of water and shake gently
5. a cloudy-white colour indicates the presence of a liquid

Question 20

What is a saturated fatty acid?

Answer 20

a fatty acid that has no double bonds between carbons

Question 21

What is an unsaturated fatty acid?

Answer 21

a fatty acid that has double bonds between carbons

Question 22

What are the functions of proteins?

Answer 22

• enzymes
• transport
• movement
• cell recognition
• channels

Question 23

What are the bases in DNA?

Answer 23

A, T, C, G

Question 24

What are the bases in RNA?

Answer 24

A, U, C, G

Question 25

What are the purine bases?

Answer 25

adenine and guanine

Question 26

What are the pyrimidine bases?

Answer 26

thymine, cytosine, uracil (for RNA)

Question 27

What type of bond forms between a phosphate and a sugar?

Answer 27

phosphodiester

Question 28

How many bonds are between C and G?

Answer 28

3

Question 29

How many bonds are between A and T

Answer 29

2

Question 30

What type of bond forms between 2 nucleotides?

Answer 30

hydrogen

Question 31

What is ATP made out of?

Answer 31

- 3 phosphates - ribose sugar - adenine

Question 32

What are nucleotides made out of (DNA)?

Answer 32

- phosphate group - deoxyribose sugar - nitrogenous base

Question 33

Describe the structure of a DNA molecule

Answer 33

- double helix with two polynucleotide chains - held together by hydrogen bonds between specific complementary base pairs -

Question 34

What are the three types of RNA

Answer 34

- Messenger RNA (mRNA) - Transfer RNA (tRNA) - Ribosomal RNA (rRNA)

Question 35

Why are phosphate ions important in the structure of DNA?

Answer 35

- they create a super strong sugar-phosphate backbone along with the deoxyribose sugar - the phosphate acts as a binding agent

Question 36

Why is DNA replication called semi-conservative?

Answer 36

- each new DNA molecule contains one of the original (parental) DNA strands, and one new (daughter) strand.

Question 37

What is ADP made out of?

Answer 37

- adenine - ribose sugar - 2 phosphates

Question 38

Describe and explain the induced fit model

Answer 38

- substrate enters an enzyme's binding - enzyme alters its shape slightly (conformational change) to the substrate - ensures an ideal binding arrangement - so it maximises the ability of the enzyme to catalyse the substance.

Question 39

Explain the lock and key hypothesis

Answer 39

- enzymes are globular and therefore have a very specific tertiary structure. - this means that they have a very specific active site which specific substrates bond to, being catalysed. - both enzyme and substrate are rigid structures.

Question 40

Which from the model/hypothesis is used today?

Answer 40

induced fit

Question 41

What are the two types of enzyme inhibiton?

Answer 41

- competitive - non-competitive

Question 42

What is competitive enzyme inhibition?

Question 43

What is non-competitive enzyme inhibition?