B8-photosynthesis

Question 1

how is energy transferred from the environment to the chloroplasts

Answer 1

light

Question 2

what is an endothermic reaction

Answer 2

a reaction that needs input from the environment

Question 3

what is the word equation for photosynthesis

Answer 3

light

carbon dioxide + water –> glucose + oxygen

Question 4

what are the products of photosynthesis

Answer 4

glucose and oxygen

Question 5

how do you know a plant is photosynthesizing

Answer 5

you test if its producing oxygen

Question 6

how do you test if a plant is producing oxygen

Answer 6

put pondweed in a test tube full of co2 water and turn the lamp on. If bubbles are produced, oxygen is present.

Question 7

how are leaves adapted for photosynthesis

Answer 7

• they have a large surface area to maximise the amount of light falls on it
• leaves are thin, shortening diffusion distances
• they have veins which gives them water from the xylem
• there guard ells regulate gas exchange
• they have air spaces for oxygen and carbon dioxide to diffuse in and out of the cell easily

Question 8

what do chlorophyll do

Answer 8

they absorb light

Question 9

how are algae adapted to photosynthesize

Answer 9

they have a large surface area and absorb C02 that is dissolved in the waterhow

Question 10

what are limiting factors

Answer 10

factors that can limit the amount of photosythesis

Question 11

how does light affect photosynthesis

Answer 11

in most cases, the brighter the light the faster the rate of photosynthesis

Question 12

how does temperature affect photosynthesis

Answer 12

the higher the temperature the faster the rate of photosynthesis, however photosynthesis is controlled by enzymes and at 40-50 degrees the enzymes can denature meaning the rate of photosynthesis will fall

Question 13

how is carbon dioxide a limiting factor

Answer 13

the higher the concentration of carbon dioxide, the higher the rate of photosynthesis. As there is only a small amount in the atmosphere it is a limiting factor, so people use greenhouses to overcome this

Question 14

how does light intensity influence the rate of photosynthesis

Answer 14

put pond weed in a test tube full of co2 water and turn the lamp on 10 cm away from the plant. Time a minute and count the bubbles produced. Move the plant 20,30 and 40 cm away and repeat. Record results and plot a graph.

Question 15

How is the amount of chlorophyll a limiting factor

Answer 15

If a plant has less chlorophyll it photosynthesises less. This could cause the plant to die

Question 16

how is light intensity and distance linked

Answer 16

light intensity is inversely proportional to the square of distance

Question 17

how often do plants respire

Answer 17

they respire all the time

Question 18

what is the word equation for respiration

Answer 18

glucose + oxygen–> carbon dioxide + water

Question 19

what is the immediate thing glucose is used for

Answer 19

respiration

Question 20

what is glucose used for

Answer 20

starch for storage
fats and oils for storage
amino acids for protein
cellulose for making cell walls
respiration

Question 21

Is starch soluble in water

Answer 21

no

Question 22

how do you test for starch

Answer 22

use the iodine test, if it turns blue/black, starch is present

Question 23

can plants live in areas like bogs with low amounts of nitrate ions

Answer 23

no as there are very few nutrients in the soil

Question 24

how are plants like the venus fly trap adapted to live in ares with low amounts of minerals

Answer 24

they collect their nutrients from insects they eat.

Question 25

what do plants need to make amino acids

Answer 25

nitrate ions from soil or water

Question 26

what are lipids used for in plants

Answer 26

strengthening cell walls or providing an energy store for seeds

Question 27

is glucose soluble in water

Answer 27

yes

Question 28

why do farmers want plants to photosynthesise a lot

Answer 28

so they get more produce and make more money

Question 29

how do farmers maximise photosynthesis in plants in their fields

Answer 29

they use huge plastic poly tunnels which act similar to how a greenhouse would

Question 30

how do greenhouses make plants grow more

Answer 30

the temperature is warmer and there is more carbon dioxide in them

Question 31

how are commercial greenhouses taking advantage of limiting factors

Answer 31

they make sure there is the perfect temperature, light and co2 levels. They sometimes use hydroponics, where they grow plants in water to give them the perfect balance of all the nutrients

Question 32

what are the benefits to the huge greenhouses

Answer 32

plants are bigger, the turnover is fast, meaning the profit is higher. The crops are also cleaner

Question 33

what are the costs of the hydroponic greenhouses

Answer 33

it takes a lot of electricity and gas as well as a lot of planning and expensive computers and monitoring equipment

Question 34

why do farmers need to look at the economics of hydroponics

Answer 34

it costs a lot of money to set up and maintain but the crops grow faster