Topic 1 A

Question 1

What are Polymers?

Answer 1

Long chains of monomers joined together by a condensation reaction

Question 2

What is a condensation reaction?

Answer 2

Forming a chemical bond between two molecules, releasing a molecule of water

Question 3

What is a hydrolysis reaction?

Answer 3

breaking a chemical bond between molecules using a water molecule

Question 4

What are the monomers carbohydrates made from?

Answer 4

Monosacharides

Question 5

What are the monosaccharides?

Answer 5

Glucose, fructose and galactose

Question 6

What is a disaccharide?

Answer 6

Two monosaccharides joined together by a condensation reaction (glycosidic bond)

Question 7

What is sucrose made from?

Answer 7

alpha glucose and fructose

Question 8

What is maltose made from?

Answer 8

Two alpha glucose

Question 9

What is lactose made from?

Answer 9

beta glucose and galactose

Question 10

What is the test for sugars?

Answer 10

Benedict test

Question 11

How to test for reducing sugars?

Answer 11

Heat sample with benedict’s reagent, positive result will be green, yellow orange and brick red

Question 12

How to test for non reducing sugars?

Answer 12

If reducing sugar test is negative, heat with HCL then add sodium hydrogencarbonate to neutralise. Reheat with benedicts, positive, green yellow, orange and brick red

Question 13

What is a polysaccharide?

Answer 13

More than two monosaccharides joined together via condensation reactions (glycosidic bond)

Question 14

What is starch made from?

Answer 14

Alpha glucose

Question 15

Starch shape to function

Answer 15

Insoluble- doesnt affect water potential
Branched- break down easily
Compact- good for storage

Question 16

What is glycogen made from?

Answer 16

Alpha glucose

Question 17

Glycogen shape to function

Answer 17

Branched- easily broken down
Compact- good for storage
Acts as energy store

Question 18

What is cellulose made from?

Answer 18

Beta glucose

Question 19

Cellulose shape to function

Answer 19

Microfibrils- strong for support
Long straight chains- for support

Question 20

What is the test for starch?

Answer 20

Iodine

Question 21

How do you do the iodine test?

Answer 21

Add iodine dissolved in potassium iodide solution to sample. If it turns blue black, starch is present

Question 22

What is the structure of a triglyceride?

Answer 22

One glycerol molecule and three fatty acid tails that are hydrocarbon

Question 23

What is the difference between a saturated and unsaturated fatty acid?

Answer 23

Unsaturated have double carbon bonds

Question 24

How is a triglyceride made?

Answer 24

A condensation reaction between the glycerol and fatty acid tails, forming an ester bond

Question 25

What is the structure of a phospholipid?

Answer 25

Phosphate group, glycerol and two fatty acid tails

Question 26

What are the properties of a triglyceride?

Answer 26

Used as energy storage, insoluble so don't affect water potential, hydrophobic tails, hydrophilic glycerol heads

Question 27

What are the properties of a phospholipid?

Answer 27

Make up bilayer of cell membrane, hydrophobic tails, hydrophilic phospholipid heads, prevents water soluble substances from passing through easily

Question 28

What is the test for lipids?

Answer 28

Milky emulsion

Question 29

How do you carry out the milky emulsion test?

Answer 29

Shake the sample with ethanol for a minute then pour into water. A milky emulsion should form on the top

Question 30

What are proteins made from?

Answer 30

Amino acids

Question 31

What is the structure of an amino acid?

Answer 31

Amine group, carboxyl group, r group and a hydrogen molecule attached to a carbon molecule.

Question 32

What is a dipeptide?

Answer 32

Two amino acids joined together (peptide bond)

Question 33

What is a polypeptide?

Answer 33

More than two amino acids joined together

Question 34

What is the bond formed between amino acids?

Answer 34

Peptide bond

Question 35

What is the primary structure of a protein?

Answer 35

Sequence of amino acids

Question 36

What is the secondary structure of a protein?

Answer 36

Hydrogen bonds form and the chain coils into an alpha helix or folds into beta pleated sheets

Question 37

What is the tertiary structure of a protein?

Answer 37

Coiled and folded further, ionic bonds, disulfide bridges and hydrogen bonds are formed. For most this is the final 3D structure

Question 38

What is the quaternary structure of a protein?

Answer 38

More than one polypeptide chain held together

Question 39

What is the test for proteins?

Answer 39

Biuret

Question 40

How is the biuret test carried out?

Answer 40

Add sodium hydroxide to make alkaline, then add copper sulfate solution. Positive=lilac

Question 41

What are enzymes?

Answer 41

Biological catalysts that speed up the rate ofreactions

Question 42

What is the activation energy?

Answer 42

The amount of energy that needs to be supplied to the chemicals before the reaction starts

Question 43

How do enzymes speed up reactions?

Answer 43

Lower activation energy

Question 44

What is the lock and key model?

Answer 44

The substrate perfectly fits the active site of an enzyme

Question 45

What is the induced fit model?

Answer 45

The active site changes shape to fit the substrate.

Question 46

What are properties of an enzyme?

Answer 46

Specific

Question 47

What factors affect enzyme activity?

Answer 47

Temperature, pH, Conc of substrate and conc of enzyme

Question 48

What is the optimum temperature for an enzyme in the human body?

Answer 48

37c

Question 49

What is the optimum pH for an enzyme in the body?

Answer 49

7

Question 50

How does temp affect enzymes?

Answer 50

Kinetic energy, more collisions, more ES complexes. Too high, breaks bonds, changes shape, cannot fit substrate

Question 51

How does pH effect enzymes?

Answer 51

H+ and OH- ions can disrupt the ionic and hydrogen bonds causing a shape change.

Question 52

What is a competitive inhibitor?

Answer 52

Competes with substrate for active site

Question 53

What is a non competitive inhibitor?

Answer 53

Binds somewhere else on the enzyme (allosteric site), cause a change in the tertiary structure, no longer complementary.