Topic 9 - Plant nutrition and transport

Question 1

What is the definition of photosynthesis?

Answer 1

Chemical reaction that absorbs light energy and converts it to chemical energy in the form of glucose/starch in the presence of light and chlorophyll.

Question 2

What is the word equation for photosynthesis?

Answer 2

Carbon dioxide + Water –> Glucose + Oxygen

Question 3

What is the chemical equation for photosythesis?

Answer 3

6CO2 + 6H2O –> C6H12O6 + 6O2

Question 4

What are the 3 things that affect the rate of photosynthesis? (3)

Answer 4

1. Varying the carbon dioxide concentration
2. Light intensity
3. Temperature

Question 5

Why do plants require mineral ions?

Answer 5

For growth

Question 6

Why do plants require magnesium ions?

Answer 6

For chlorophyll

Question 7

Why do plants require nitrate ions?

Answer 7

For amino acid

Question 8

What does a lack of magnesium do to a plant?

Answer 8

A lack of magnesium ions leads to chlorosis as their isn’t enough magnesium required to make chlorophyll so this causes a leaf to turn lighter

Question 9

What does a lack of nitrate do to a plant?

Answer 9

A lack of nitrate ions causes stunted growth of the leaf and discolouration

Question 10

Describe the test for starch in a leaf? (9)

Answer 10

(1) Half fill a 250 cm3 beaker with warm water and place it on a tripod over a Bunsen burner. Heat the water till it boils and then turn down the Bunsen flame sufficiently to keep the water at boiling point.

(2) Place the leaf (from a destarched plant) into the boiling water for at least 5 minute. This will kill the cells, stop all chemical reactions and make the leaf permeable to alcohol and iodine solution later on.

(3) TURN OFF THE BUNSEN BURNER

(4) With the forceps, push the leaf carefully to the bottom of a test-tube and cover it with ethanol.

(5) Place the test-tube in the hot water and leave it for 5 minutes. The alcohol will boil and dissolve out the chlorophyll in the leaf.

(6) Use a test-tube holder to remove the test-tube from the water bath and tip the green alcoholic solution into the beaker for waste alcohol but take care not to tip the leaf out as well. Your leaf should be white or very pale green.

(7) Fill the test-tube with cold water and the leaf will should float to the top.

(8) Use forceps to spread the leaf flat in a petri dish. Use a dropping pipette cover the leaf with iodine solution for one minute.

(9) Take the leaf to the sink and holding it on the petri dish, wash away the iodine solution with some cold water.

Question 11

How is the waxy cuticle adapted for photosynthesis?

Answer 11

A protective layer that allows light to enter the leaf. It is waterproof in order to prevent water loss by evaporation.

Question 12

How is the Epidermis adapted for photosynthesis?

Answer 12

transparent, physical defence layer that does not contain chloroplasts. It allows light into the leaf.

Question 13

How is the Palisade mesophyll layer adapted for photosynthesis?

Answer 13

Regularly shaped allowing many to pack together closely at the top of the leaf. These cells also have many chloroplasts in order to trap as much light as possible.

Question 14

What is the Palisade mesophyll layer?

Answer 14

Plant tissue containing closely packed cells in the upper layer of a leaf.

Question 15

How is the spongy mesophyll layer adapted for photosynthesis?

Answer 15

have very few chloroplasts and a large surface area to increase the diffusion of carbon dioxide and oxygen.

Question 16

What is the spongy mesophyll layer?

Answer 16

The plant tissue in a leaf which has loosely packed cells and air spaces between them to allow gas exchange.

Question 17

How is the Stomata layer adapted for photosynthesis?

Answer 17

allow carbon dioxide and oxygen to enter and leave the leaf.

Question 18

What is the Stomata?

Answer 18

Small pores usually found on the lower surface of the leaf

Question 19

What is the stomata surrounded with?

Answer 19

Each stoma is surrounded by two guard cells that control its opening and closing. Stomata are usually open during the day and closed at night.

Question 20

Describe what is happening in a part A of a rate of photosynthesis and light graph?

Answer 20

Part A: As light intensity increases the rate of photosynthesis also increases, light is the limiting factor here

Question 21

Describe what is happening in a part B of a rate of photosynthesis and light graph?

Answer 21

Part B: The line patios out because there is an other factor of photosynthesis that has a shortage meaning the photosynthesis will stop in till the factor with a shortage isn’t in a shortage anymore

Question 22

Describe what is happening in a part A of a rate of photosynthesis and carbon dioxide concentration graph?

Answer 22

Part A: As carbon dioxide concentration increases the rate of photosynthesis also will increases, carbon dioxide is the limiting factor here

Question 23

Describe what is happening in a part B of a rate of photosynthesis and carbon dioxide concentration graph?

Answer 23

Part B: The graph will level out at the point when another limiting factor prevents any further increase in the rate of photosynthesis.

Question 24

Describe what is happening in a part A of a rate of photosynthesis and temperature graph?

Answer 24

Part A: The rate of photosynthesis will increase as temperature increases until the optimum temperature is reached, temperature is the limiting factor here

Question 25

Describe what is happening in a part B of a rate of photosynthesis and temperature graph?

Answer 25

Part B: The rate will then decrease as the temperature increases further. This is because the enzymes involved will become denatured, meaning their active site will start to change shape

Question 26

Describe the experiment for the pond weed investigation? (5)

Answer 26

1. Set up a boiling tube containing 45 cmof sodium hydrogencarbonate solution (1%). Allow the tube to stand for a few minutes and shake to disperse any air bubbles that might form.
2. Cut a piece of the pondweed,Cabomba. The pondweed should be 8 cm long.
3. Use forceps to place the pondweed in the boiling tube carefully. Make sure that you don’t damage the pondweed, or cause the liquid to overflow.
4. Position the boiling tube so that the pondweed is 10 cm away from the light source. Allow the boiling tube to stand for five minutes. Count the number of bubbles emerging from the cut end of the stems in one minute. Repeat the count five times and record your results.
5. Calculate the average number of bubbles produced per minute. Repeat the experiment at different distances away from the light source.

Question 27

Molecules it transports in the xylem tissue?

Answer 27

Water and minerals

Question 28

Name of process of transporting the xylem tissues?

Answer 28

Transpiration (travels up through the stem to the lead then diffuses out of the stomata) (creates low water potential in roots and high outside, so osmosis occurs)

Question 29

What are the xylem tissues cell wall made of?

Answer 29

Cellulose

Question 30

Are the xylem tissues dead or live cells?

Answer 30

Dead cells (traps the water and brings it up the stem, doesn’t absorb it into the cell)

Question 31

What is the direction of flow in the xylem tissues?

Answer 31

Upwards from roots to leaves (one way)

Question 32

Key features of the xylem tissues? (5)

Answer 32

1. Supplies water for the leaf cells to carry out photosynthesis
2. Carries minerals ions dissolved in the water
3. Provides water to keep the plant cells turgid
4. Allows evaporation from the leaf structure, which cools the leaf, in a similar way to swear cooling the human skin
5. Lignin - woody material (push the water away so the water doesn’t stick to it)

Question 33

Key features of the phloem tissues? (4)

Answer 33

1. Growing parts of the plant for immediate use
2. Storage organs such as bulbs and tubers
3. Developing seeds
4. Plate - gives it support and structure

Question 34

What is the direction of flow in the phloem tissues?

Answer 34

Both up and down the stem

Question 35

Are the phloem tissues dead or live cells?

Answer 35

Living cells

Question 36

What are the phloem tissues cell wall made of?

Answer 36

Cellulose

Question 37

Name of process of transporting the phloem tissues?

Answer 37

Translocation (moving things)

Question 38

Molecules it transports in the phloem tissue?

Answer 38

Glucose