topic 1

Question 1

what elements is a carbohydrate made of?

Answer 1

carbon, hydrogen, oxygen

Question 2

what is a monomer?

Answer 2

repeating unit from which larger molecules are made

Question 3

what is the structure of starch?

Answer 3

alpha glucose, amylose and amylopectin, insoluble

Question 4

what is the structure of glycogen?

Answer 4

side branches, compact, alpha glucose

Question 5

what is the structure of cellulose?

Answer 5

long, unbranched, beta glucose, microfibrils

Question 6

what is the difference between alpha glucose and beta glucose?

Answer 6

h and oh are the opposite way round on the right hand side

Question 7

what is condensation?

Answer 7

two molecules are joined which releases water

Question 8

what is hydrolysis?

Answer 8

breaks the polymer using water

Question 9

what is maltose made of?

Answer 9

2 alpha glucose

Question 10

what is sucrose made of?

Answer 10

glucose and fructose

Question 11

what is lactose made of?

Answer 11

glucose and galactose

Question 12

what is a lipid made of?

Answer 12

glycerol and 3 fatty acids

Question 13

what bonds are present in lipids?

Answer 13

ester bond

Question 14

what bonds are present in carbohydrates?

Answer 14

glycosidic bond

Question 15

what bonds are present in proteins?

Answer 15

peptide bonds

Question 16

what is a saturated fatty acid?

Answer 16

no double bonds

Question 17

what is an unsaturated fatty acid?

Answer 17

at least one carbon double bond=kinked chain

Question 18

what is a phospholipid?

Answer 18

one fatty acid replaced by a phosphate group, makes up a bilayer

Question 19

what is a triglyceride?

Answer 19

energy storage, long, insoluble

Question 20

what is the primary structure of a protein?

Answer 20

sequence of amino acids

Question 21

what is the secondary structure of a protein?

Answer 21

hydrogen bond, coil to form an alpha helix or fold to form a beta pleated sheet

Question 22

what is the tertiary structure of a protein?

Answer 22

hydrogen and ionic bonds, disulphide bridges, 3D structure

Question 23

what is the quaternary structure of a protein?

Answer 23

when several polypeptides join together

Question 24

what are enzymes?

Answer 24

biological catalysts, proteins

Question 25

what is the job of an enzyme?

Answer 25

to lower the activation energy of a reaction

Question 26

what are the two models for enzymes?

Answer 26

lock and key hypothesis, induced fit model

Question 27

how does temperature affect enzyme activity?

Answer 27

increases up to a certain point, then denatures

Question 28

how does enzyme activity affect pH?

Answer 28

increases up to a certain point, then denatures

Question 29

how does substrate concentration affect enzyme activity?

Answer 29

increases up to saturation point, then levels off

Question 30

what is competitive inhibition?

Answer 30

when it competes to block the active site

Question 31

what is non competitive inhibition?

Answer 31

when it causes the enzyme to bind away from its active site

Question 32

what is the full name for DNA?

Answer 32

deoxyribonucleic acid

Question 33

what is the full name for RNA?

Answer 33

ribonucleic acid

Question 34

what is the job of DNA?

Answer 34

to store genetic information

Question 35

what is the job of RNA?

Answer 35

to transfer genetic information from DNA to ribosomes

Question 36

what is a nucleotide made of?

Answer 36

phosphate group, pentose sugar, nitrogen containing base

Question 37

what bases does DNA contain?

Answer 37

adenine, cytosine, thymine, uracil

Question 38

what bases does RNA contain?

Answer 38

adenine, uracil, cytosine, guanine

Question 39

what bonds are formed to join nucleotides?

Answer 39

phosphodiester bonds

Question 40

what is the structure of a DNA strand?

Answer 40

2 polynucleotide strands, antiparallel, double helix

Question 41

who proposed the structure of the DNA double helix?

Answer 41

Watson and Crick

Question 42

how does semi conservative replication work?

Answer 42

1) DNA helicase breaks hydrogen bonds between bases on polynucleotide strands 2) DNA helix unwinds to form 2 strands 3) original strand acts as a template 4) complementary base pairing occurs- free nucleotides are attracted to their exposed bases 5) condensation reaction joins nucleotides which is catalysed by DNA polymerase

Question 43

what direction is the new strand of DNA made in?

Answer 43

5' to 3' direction, active site of polymerase complements the 3' end, moves into the 3' to 5' direction

Question 44

who proposed evidence for semi conservative replication?

Answer 44

Meselson and Stahl

Question 45

how did scientists propose the evidence for semi conservative replication?

Answer 45

heavy nitrogen replicates in the light broth, combination of heavy and light strands suggests semi conservative replication

Question 46

what charges are present in a water molecule?

Answer 46

``` hydrogen= slightly positive, oxygen= slightly negative ```

Question 47

why is it good for water to have a high latent heat of vaporisation?

Answer 47

can get cool without losing too much water

Question 48

why is it good for water to have a high specific heat capacity?

Answer 48

no rapid temperature changes, can act as a buffer

Question 49

what is ATP made of?

Answer 49

adenine, ribose, phosphate

Question 50

how many phosphate groups does ATP have?

Answer 50

3

Question 51

what does ATP do?

Answer 51

diffuses to the part of cell that needs energy

Question 52

why is ATP important?

Answer 52

cells cannot get their energy directly from glucose

Question 53

how does ATP turn into ADP and Pi?

Answer 53

hydrolysis reaction, catalysed by ATP hydrolase

Question 54

how does ADP and Pi change into ATP?

Answer 54

condensation reaction, catalysed by ATP synthase

Question 55

what is an ion?

Answer 55

molecule with an electric charge

Question 56

what is a positive ion?

Answer 56

cation

Question 57

what is a negative ion?

Answer 57

anion

Question 58

what does an inorganic ion not contain?

Answer 58

carbon

Question 59

what is the role of an iron ion?

Answer 59

part of haemoglobin

Question 60

what is the role of a hydrogen ion?

Answer 60

determines pH, more ions=lower pH

Question 61

what is the role of a sodium ion?

Answer 61

transports glucose and amino acids across the membrane

Question 62

what is the role of a phosphate ion?

Answer 62

part of ATP and DNA