P1 - 2c biological molecules and enzymes

Question 1

what does water do?

Answer 1

• hydration

- solvent

Question 2

what do lipids (fats and oils) do?

Answer 2

store and give energy

Question 3

what do proteins do?

Answer 3

recovery and repair, building tissues, part of enzymes

Question 4

what do carbohydrates do?

Answer 4

give energy

Question 5

what type of molecule is water?

Answer 5

compund

Question 6

all nutrients are…

Answer 6

organic chemicals because they contain carbon

Question 7

what are carbohydrates are made of?

Answer 7

simple sugars (monosaccharides and disaccharides)

Question 8

what are other forms of carbohydrates?

Answer 8

starch or glucose

Question 9

Proteins are made up of

Answer 9

amino acids

Question 10

lipids (oils or fats) are made up of

Answer 10

glycerol and fatty acid molecules

Question 11

what do enzymes do

Answer 11

break down substrates into products

Question 12

Monosaccharides

Answer 12

simple sugar

Question 13

Disaccharide

Answer 13

A double sugar molecule made of two monosaccharides bonded together

Question 14

Polysaccharides

Answer 14

Carbohydrates that are made up of more than two monosaccharides

Question 15

what colour does benedict’s solution turn when a reducing sugar (glucose) is present?

Answer 15

red

Question 16

what do you use to test for starch?

Answer 16

iodine solution

Question 17

what colour does iodine solution turn when sugar/starch is present?

Answer 17

dark blue

Question 18

what does the sugar, glucose make?

Answer 18

glycogen and cellulose

Question 19

how do you test for fats and oils?

Answer 19

you dissolve the sample in ethanol, add it to water and shake. the lipids will leave a layer.
- ethanol emulsion test

Question 20

Adenine (A) pairs with

Answer 20

Thymine (T)

Question 21

Cytosine (C) pairs with

Answer 21

Guanine (G)

Question 22

enzymes are

Answer 22

biological catalysts, not used up, are proteins. they also have substrates that are specific to them.
made up of chains of amino acids

Question 23

when the temp gets too hot, enzymes…

Answer 23

denature (shape changes) because the bonds will break

Question 24

enzymes also get effected by

Answer 24

pH levels, this can also denature them

- optimum pH is 7 but not always

Question 25

Carbohydrases break down…

Answer 25

carbohydrates into simple sugars

Question 26

proteases break down

Answer 26

Proteins into amino acids

Question 27

lipases break down

Answer 27

lipids into fatty acids and glycerol

Question 28

what are metabolic reactions?

Answer 28

all of the chemical reactions that happen in a cell or an organism to keep it alive
- when enzymes seep up useful chemical reactions in the body without having to raise the temperature

Question 29

what is the place the substrate fits into the enzyme called?

Answer 29

active site

Question 30

how do you test for glucose?

Answer 30

Benedict’s solution

Question 31

how do you test for proteins?

Answer 31

biuret, turns purple colour is protein is present

Question 32

how does temperature affect enzymes?

Answer 32

when it is very cold they work very slowly
when its normal body temp (37C) they work at optimum level
when its very hot they become denatured and the active site will loose the shape needed

Question 33

what is the result of the ethanol emulsion test?

Answer 33

cloudy emulsion, layer of lipids

Question 34

why are enzymes necessary?

Answer 34

maintain reaction speed of all metabolic reactions at a rate that can sustain life

Question 35

how does pH affect enzymes?

Answer 35

if it is too high or low the bonds can be destroyed or disrupted (shape change)
- optimum pH level is 7 for most enzymes

Question 36

why does the optimum pH level of enzymes differ?

Answer 36

it depends on wether they were produced in acidic (stomach) or alkaline conditions

• acidic would have lower optimum pH levels
• alkaline has higher ones

Question 37

how do you investigate the effect of temperature on the activity on an enzyme, amylase?

Answer 37

1. heat starch solution to temperature being investigated
2. add a drop of iodine to each of the wells in the spotting tile
3. add amylase to starch solution
4. start the timer for a min straight away
5. every minute add a drop of solution to iodine in wells.
6. there will be a change in colour throughout the drops bc the temp will be rising

Question 38

how do you investigate the effect of pH on the activity on an enzyme, amylase?

Answer 38

1. add iodine to spotting tile
2. add amylase and buffer solution to a test tube, mix then add starch solution
3. every 10 seconds add a droplet of solution to a well
4. repeat until there is no change in colour
5. record time taken for experiment to be completed

Question 39

what is the buffer solution?

Answer 39

has diff pH levels