Photosynthesis

Question 1

Word Equation

Answer 1

Carbon dioxide + water –>(light above) glucose + oxygen

Question 2

Symbol Equation

Answer 2

6CO₂ + 6H₂O –>(light above) C₆H₁₂O₆ + 6O₂

Question 3

Reactants (2)

Answer 3

Carbon Dioxide / Water

Question 4

Products (2)

Answer 4

Oxygen / Glucose

Question 5

Structure of a Leaf

Answer 5

Waxy cuticle, Upper epidermis, Palisade mesophyll, Spongy mesophyll, Lower epidermis, Guard cells, Stoma(ta), Xylem, Phloem

Question 6

Waxy Cuticle

Answer 6

Transparent to allow sunlight in. Prevents water loss

Question 7

Upper Epidermis

Answer 7

Houses waxy cuticle, transparent to allow sunlight in

Question 8

Palisade Mesophyll

Answer 8

Houses cells specialized for photosynthesis and contain chlorophyll. Tightly packed to hold more cells.

Question 9

Spongy Mesophyll

Answer 9

Houses more photosynthetic cells, xylem, and phloem cells, air pockets, lets CO₂ in and O₂ out

Question 10

Lower Epidermis

Answer 10

Houses guard cells and stoma(ta)

Question 11

Guard Cells

Answer 11

Open(flaccid) and close(turgid) during day and night, “protects” the stoma(ta)

Question 12

Stoma(ta)

Answer 12

The gap between guard cells that lets CO₂ in and O₂ + H₂O out

Question 13

Xylem

Answer 13

Transports water + dissolved minerals to leaves

Question 14

Phloem

Answer 14

Transports sugars made in photosynthesis to other parts of the plant

Question 15

Adaptations of a Leaf

Answer 15

1. Broad + Large surface area 2. Chloroplasts found in Palisade layer 3. Upper Epidermis is transparent for light 4. Leaves have vascular bundles for delivery (vein)
2. Waxy Cuticle reduces water loss by evaporation + transparent for light 6. Stoma(ta) allow CO₂ in to diffuse directly into leaf

Question 16

Starch to test for Glucose

Answer 16

1. Grow 2 leaves, 1 in dark place, 1 in a light place
2. Take the leaf out to test after a certain amount of time
3. Put leaf into boiling water to stop chemical reactions
4. Put leaf into a boiling tube with ethanol and heat in a water bath until it boils
5. Rinse in cold water and add iodine solution
6. If leaf turns blue/black starch is present, it stays yellow starch isn’t present

Question 17

Limiting Factor Definition

Answer 17

Something that is needed for something to happen so if it is not present then that something won’t happen

Question 18

Limiting Factors of Photosynthesis

Answer 18

Light, Temperature, and CO₂

Question 19

Light

Answer 19

Needed to split the water into Hydrogen and Oxygen molecules for H to react with CO₂ - Glucose

Question 20

Temperature

Answer 20

Needed because each plant has an optimum temperature so the enzymes can work faster at photosynthesizing

Question 21

CO₂

Answer 21

Needed to react with the H molecules - Glucose

Question 22

Role of Chlorophyll

Answer 22

Traps light energy from the sun used to combine CO₂ and H₂O into sugars

Question 23

Organs of a Plant

Answer 23

Root System + Shoot System(Vegetative and Reproductive)

Question 24

Root System

Answer 24

Supports the plant, absorbs water and minerals, usually underground

Question 25

Shoot System

Answer 25

Vegetative (non-reproductive) includes leaves and stems, Reproductive parts include flowers and fruits, generally grows above ground and absorbs light for photosynthesis

Question 26

Difference between Xylem and Phloem

Answer 26

Xylem transports water and nutrients in a unidirectional way, Phloem transports sugars in a bidirectional way

Question 27

Investigating Photosynthesis with varying Light Intensity

Answer 27

1. Set up the experiment 2. Make sure the syringe is empty 3. Add a small amount of sodium hydrogen carbonate to the boiling tube with pondweed to add carbon dioxide 4. You can control the temperature by placing the boiling tube with the plant in a water bath
2. Place the light at the set distance you are measuring first 6. Leave the plant to photosynthesize for the set amount of time 7. The oxygen produced will collect in the capillary tube 8. Use the gas syringe to draw up the gas bubble alongside the ruler and measure the length of it (proportional to the volume of O₂ produced) 9. Repeat this at different distances to measure the effect of sunlight

Question 28

Investigating Photosynthesis with Hydrogen Carbonate Indicator

Answer 28

1. Pour some hydrogen carbonate indicator into 4 tubes
2. Put a leaf in 2 of the 4 tubes, the 4th is your control
3. Wrap the 2nd tube in foil and the 3rd in gauze 4. Leave them to photosynthesize/respirate for your set amount of time 5. Unwrap the 2nd and 3rd tubes and compare the first 3 tubes with the 4th one

Question 29

What results would you expect to see?

Answer 29

The 1st tube would be purple because there is a decrease in CO₂ as the plant was photosynthesizing more than respiring. The 2nd tube would be yellow because there is an increase in CO₂ as the plant was respiring because there was no light for it to photosynthesize. The 3rd tube would still be red because there was light but not enough to photosynthesize more than respire, the rate of respiration and photosynthesis was the same.

Question 30

What does it do during day + night

Answer 30

Photosynthesis + Respiration during the day but less of the latter than the former. Respiration during the night

Question 31

Magnesium ions

Answer 31

Magnesium is needed for the chlorophyll to capture the sunlight energy to photosynthesize. This gives the plant its green color.

Question 32

Nitrate ions

Answer 32

Nitrates are needed to produce amino acids that produce proteins. This is needed for healthy growth.