biogenetics revision

Question 1

define photosynthesis

Answer 1

plants making use of the sun’s energy to make food.

Question 2

Plants make glucose from what?

Answer 2

CO2 and water, using energy from light.

Question 3

Photosynthesis is [endothermic/exothermic] (pick one)

Answer 3

Endothermic

Question 4

Why is photosynthesis an endothermic reaction?

Answer 4

Because photosynthesis needs an input of energy from the environment

Question 5

What is the word equation for photosynthesis?

Answer 5

carbon dioxide + water —(light)—-> glucose + oxygen

Question 6

What is the symbol equation for photosynthesis?

Answer 6

CO2 + H2O —–> C6H12O6 + O2

Question 7

summarise an investigation for the effect of light intensity on the rate of photosynthesis:

Answer 7

1. cut a piece of pond weed and place it in a boiling tube filled with sodium hydrogen carbonate solution
2. set up an LED light and 10cm from the tube, leave to settle
3. start the stopwatch and count the no. of bubbles in 1 minute.
4. repeat and calculate the mean
5. repeat, altering the lamp’s distance

Question 8

Why do we fill the boiling tube with sodium hydrogen carbonate solution in a light intensity investigation?

Answer 8

Makes sure that CO2 is not a limiting factor in the experiment.

Question 9

Why do we use specifically LED lamps in a light intensity investigation?

Answer 9

LED lamps produce less heat, which makes the experiment more fair because it reduces the effect of temperature on the experiment.

Question 10

The rate of photosynthesis [increases/decreases] with higher concentrations of CO2, up to a point.

Answer 10

The rate of photosynthesis increases with higher concentrations of CO2, up to a point.

Question 11

Name 3 limiting factors of photosynthesis.

Answer 11

light intensity, temperature, amount of chlorophyll.

Question 12

photosynthesis is an __________ controlled reaction.

Answer 12

photosynthesis is an [enzyme] controlled reaction.

Question 13

Because photosynthesis is an enzyme controlled reaction, if the temperature increases too much, the enzymes will become ____________ and the _____ of photosynthesis will __________ and ______.

Answer 13

Because photosynthesis is an enzyme controlled reaction, if the temperature increases too much, the enzymes will become [denatured] and the [rate] of photosynthesis will [decrease] and [stop].

Question 14

the rate of photosynthesis [increases/decreases] with light intensity [to a point/forever].

Answer 14

the rate of photosynthesis [increases] with light intensity [to a point].

Question 15

uses of glucose 1: to produce ________ which strengthens cell walls.

Answer 15

uses of glucose 1: to produce [cellulose] which strengthens cell walls.

Question 16

uses of glucose 2: to be converted into ______ ______ for protein synthesis.

Answer 16

uses of glucose 2: to be converted into [amino acids] for protein synthesis.

Question 17

uses of glucose 3: to produce ______ or _____ for storage.

Answer 17

uses of glucose 3: to produce [fat] or [oil] for storage.

Question 18

uses of glucose 4: to be converted into insoluble ________ for storage inside cells or special areas like ______ or _______.

Answer 18

uses of glucose 4: to be converted into insoluble [starch] for storage inside cells or special areas like [roots] or [bulbs].

Question 19

Light intensity obeys the inverse ______ law. This means if you _______ the distance between the plant and the light source, you ______ the light intensity.

Answer 19

Light intensity obeys the inverse [square] law. This means if you [double] the distance between the plant and the light source, you [quarter] the light intensity.

Question 20

High light intensities might affect the rate of photosynthesis, this is caused by:
- saturation of the ______ sites in the enzymes __________ the reaction.
- bleaching of ___________.

Answer 20

High light intensities might affect the rate of photosynthesis, this is caused by:
- saturation of the [active] sites in the enzymes [cataclysing] the reaction.
- bleaching of [chlorophyll].

Question 21

what is the equation for light intensity?

Answer 21

light intensity = 1 / distance squared

Question 22

What will happen if there is a reduction in chlorophyll available in the plant?

Answer 22

If there is a reduction of chlorophyll available in the plant, then the amount of glucose produced will reduce and the plant won’t grow as well.

Question 23

Why is aerobic respiration also called cellular respiration?

Answer 23

Aerobic respiration is also called cellular respiration because the reactions for respiration occur inside the cell.

Question 24

Is respiration endothermic or exothermic?

Answer 24

respiration is exothermic.

Question 25

Why is respiration an exothermic reaction?

Answer 25

Respiration is an exothermic reaction because energy is transferred to the environment rather than from it.

Question 26

Give 3 reasons for why living organisms need energy:

Answer 26

3 reasons why living organisms need energy: - movement- enables muscles to contract - keeping a steady body temperature in a cold environment - chemical reactions

Question 27

what is the word equation for respiration?

Answer 27

glucose + oxygen -----> carbon dioxide + water

Question 28

Where does aerobic respiration happen?

Answer 28

Aerobic respiration occurs inside mitochondria

Question 29

Respiration can transfer energy in cells without oxygen. What is this called?

Answer 29

Anaerobic respiration is when respiration transfers energy in cells without oxygen.

Question 30

What is the end product of anaerobic respiration in animal cells?

Answer 30

The end product of anaerobic respiration in animal cells is lactic acid.

Question 31

What is the end product of anaerobic respiration in plant and yeast cells?

Answer 31

The end product of anaerobic respiration in plant and yeast cells is carbon dioxide and ethanol.

Question 32

What is anaerobic respiration called in yeast cells?

Answer 32

anaerobic respiration called in yeast cells is called fermentation. note- this process is economically important in the process of making alcoholic drinks and bread.

Question 33

What is metabolism?

Answer 33

Metabolism is the sum of all reactions in a cell or body.

Question 34

Name 3 or more metabolic reactions:

Answer 34

Metabolic reaction examples: - glucose to glycogen (animal cells - for storage) - glucose to cellulose (in plants) - formation of lipids - breakdown of proteins - respiration

Question 35

note whether the oxidisation of glucose is complete or incomplete in each of these: - aerobic respiration - anaerobic respiration (animal cells) - anaerobic respiration (plant cells)

Answer 35

note whether the oxidisation of glucose is complete or incomplete in each of these: - aerobic respiration complete - anaerobic respiration (animal cells) incomplete - anaerobic respiration (plant cells) incomplete

Question 36

state some things that happen in the body during anaerobic respiration.

Answer 36

- increase in heart rate - increase in breathing rate - increase in breath volume