Plant nutrition

Question 1

photosynthesis word eq

Answer 1

carbon dixoxide + water —> glucose +oxygen

Question 2

photosynthesis symbol eq

Answer 2

6co2 + 6H20 —-> c6H1206 +602

Question 3

photosyntheiss

Answer 3

photosyntheiss produces glucose using sunlight (plants make their own food)

Question 4

where does photosynthies occur

Answer 4

in the leaves inside the chloroplasts

Question 5

what does chlorophuyll do during photosyntheis

Answer 5

absorbs sunlight and uses its energy to convert carbon dioxide and water into glucose

Question 6

why is photosyntheiss important

Answer 6

becaude it converts light energy to chemical energy, which is stored in the glucose. The chemical eneergy is released when glucose is broken down during respiration

Question 7

how are leaves adapted for efficient photosynthesis

Answer 7

• leaves are broad so theres a large surface area exposed to light
• the waxy cuticle helps to reduce water loss by evaportation and protects the leaf without blocking out light
• the paliside layer (where most chloroplats are found) is at the top of the leaf to absorb more light
• spongy layer- Air spaces allow carbon dioxide to diffuse through the leaf, and increase the surface area

Question 8

what is plants rate of photosyntheiss effected by

Answer 8

• light
• co2
• temp of surroundings

Question 9

what is a limiting factor

Answer 9

something which stops photosyntheis from happening any faster. Temp, co2 and light can all be this, and it depends on enviornmental conditions

Question 10

Light on the rate of photosyntheis

Answer 10

not enough light slows down the rate of photosynthesis

chlorophyll uses light energy to perform photosyntheis, it can only do it as quickly as the light energy is arriving

Question 11

what happens if you increase light energy in photosyntheis

Answer 11

the rate of photosynthesis will increase steadily, but only up to a certain point, then it will stop

Question 12

carbon dioxide on the rate of photosyntheis

Answer 12

too little carbon dioxide slows it down.

Question 13

what happens when u increase the co2 in photosynthesis

Answer 13

it only increases the rate up to a certain point

Question 14

temperature in photosynthesis

Answer 14

as the temp increases, so does the rate of photosyntheis, until it reaches its optinum point. After this point, the plants enzymes become denatured, so the rate of photosynthesis will rapidly decrease

Question 15

all about mineral ions for growth

Answer 15

plants need certain elements so that they can produce important compounds

they get these elements from mineral ions in the soil

Question 16

what happens if there are not enough mineral ions in the soil

Answer 16

plants suffer deficiency symptons

Question 17

nitrates

Answer 17

contain nitrogen for making amino acids and protieins

Question 18

what are nitrates needed for

Answer 18

cell growth

Question 19

what happens if plants can’t get enough nitrates

Answer 19

they will be stunted and will have yellow older leaves

Question 20

phosphates

Answer 20

contain phosphorus for making DNA and cell membrances and are needed for respiration and growth

Question 21

what happens if plants dont have enough phosphates

Answer 21

they have poor root growth and purple older leaves

Question 22

potassium

Answer 22

to help enzymes needed for photosyntheis and respirtaiotn

Question 23

what happens if theres not enough potassium in the soil

Answer 23

plants have poor flower and fruit growth and discoloured leaves

Question 24

magnesium

Answer 24

needed in small amounts

neded for making chlorophyll for photosyntheis

Question 25

plants without magnesium

Answer 25

have yellow leaves

Question 26

how to test a leaf for starch

Answer 26

• first the leaf needs to be killed, by dunking it in boiling water, this stops any chemical reactions from happening inside the leaf
• next put the leaf in a boiling tube with some ethanol and heat the tube in a water bath. this gets rid of any chlorophyll inside the leaf. The leaf should end up a pale white ish colour.
• finally rinse the leaf in cold water, add a few drops of idoine and it shoukd go blue/black

Question 27

if a plant cant photosyntheise…

Answer 27

it can’t make starch

Question 28

how to show chlorophyll is needed for photosyntheis

Answer 28

using variegated (green and white) leaves. Only the green parts contain chlorophyll

1) take a variegated lead from a plant that has been exposed to light for a while. record which bits are green and which bits arent
2) test the leaf for starch, only the green parts turn blue/black
3) this shows only parts of the leaf which contain chlorophyll are able to photosyntheise and produce starch

Question 29

how to show co2 is needed for photosyntheis

Answer 29

1) get a plant and place it along with some soda lime inside a sealed bell jar, with a lamp shining onto the plant
2) the soda lime will absorb co2 out of the air in the jar
3) if you leave the plant in the jar for a while and then test the leaf for starch, it wont turn blue/black
4) this shows that no strarch has been made in the leaf, showing that c02 is needed for photosyntheis

Question 30

how to show that light is needed for photosynthesis

Answer 30

you will need to take a plant that has been grown without any light e.g. in a cupboard

cut a leaf from the plant and test it for starch

the leaf wont turn blue/black which shows that light is needed for photosyntheiss

Question 31

oxygen production shows the rate of photosyntheis

Answer 31

canadian pondweed can be used to measure the effect of light intesnity on the rate of photosynthesis. The rate at which the pondweed porduces oxygen corresponds ro rhe rate at which its photosynthesising - the faster the rate of oxygen production, the faster the rate of photosynthesis

Question 32

experiment fo oxygen showin the rate of photosyntheis

Answer 32

Place pondweed in a test tube with sodium hydrogen carbonate solution

1) A source of white light is placed at a specific distance from the pondweed.
2) The pondweed is left to photosyntheisse for a set amount of time. As it photosyntheisses, the plant will produce bubbles
3) count the amount of bubbles produced per min, then repeat the experiment using different distances of light

Question 33

problems with oxygen exp

Answer 33

bubbles too fast to count

some bubbles are bigger than others

Question 34

how to solve the problems with the oxygen experiment

Answer 34

use a measuring cylinder and funnel to measure the volume of gas produced