Photosynthesis

Question 1

Word equation for photosynthesis

Answer 1

Carbon dioxide + water —> oxygen + glucose

Question 2

Symbol equation for photosynthesis

Answer 2

6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

Question 3

What 5 main ways do plants use glucose

-for r…
—>can … the rest of … into other s…
-making c…
—>s… plant …
-making a… a…
—>… is combined with … ions to make them
-s… as o… or f…
—>glucose is turned into l… for storing in …
-s… as s…
—>turned into starch and stored in the r…, … and …
—>ready for use in …
—>starch is … so better for storing than …
—>a cell storing lots of … would d… lots of … and … up

Answer 3

-for respiration
—>can convert the rest of glucose into other substances
-making cellulose
—>strengthening plant walls
-making amino acids
—>glucose is combined with nitrate ions to make them
-stored as oils or fats
—>glucose is turned into lipids for storing in seeds
-stored as starch
—>turned into starch and stored in the roots, stem and leaves
—>ready for use in photosynthesis
—>starch is insoluble so better for storing than glucose
—>a cell storing lots of glucose would draw lots of water and swell up

Question 4

What is the rate of photosynthesis affected by

Answer 4

-light intensity
-concentration of CO2
-temperature
-chlorophyll

Question 5

When is light, CO2, chlorophyll and temperature a limiting factor

Answer 5

Light- when it is dark
CO2- when it is warm bright enough
Chlorophyll- affected by disease
Temp- in cool climates

Question 6

Photosynthesis practical

1. Equipment list: l…, r…, c…, t… t…, p…, w…, s…, c… t…
2. The lamp is placed at a specific … from the …
3. The pond weed is left to … for a … amount of …, the c… tube collects …
4. At the end the … is used to draw the … bubble in the … along a r…, where the length of the … is measured, this is … to the … of CO2 …
5. Control variables: t…, t…, p…
6. The experiment is … with the … at different … from the pondweed

Answer 6

1. Equipment list: lamp, ruler, clamp, test tube, pondweed, water, syringe, capillary tube
2. The lamp is placed at a specific distance from the pondweed
3. The pond weed is left to photosynthesise for a set amount of time, the capillary tube collects oxygen
4. At the end the syringe is used to draw the gas bubble in the tube along a ruler, where the length of the bubble is measured, this is proportional to the volume of CO2 produced
5. Control variables: time, temperature, pondweed
6. The experiment is repeated with the lamp at different distances from the pondweed

Question 7

What is the inverse square law

Answer 7

Light intensity ∝ 1/distance ²

Question 8

As distance increase what happens to light intensity in the rate of photosynthesis practical

Answer 8

Light intesity decreases, inversely proportional

Question 9

Way to artificially create the ideal environment for plants to grow

Answer 9

Greenhouse

Question 10

How do greenhouses work

-they help t… heat so the t… isn’t l…
—>in … heaters are used
—>in … if it’s too hot v… is used
-a… light is supplied at …
—>increase … time
-increase level of … by using a … heater
—>this increases the … and also increases …
-keeping plants e… protects them from p… and d…
-this is e…, but creeps are made f… and are more d… so can be h… more often

Answer 10

-they help trap heat so the temp isn’t limiting
—>in winter heaters are used
—>in summer if it’s too hot ventilation is used
-artificial light is supplied at night
—>increase photosynthesis time
-increase level of CO2 by using a paraffin heater
—>this increases the temp and also increases CO2
-keeping plants enclosed protects them from pests and diseases
-this is expensive, but creeps are made faster and are more decent so can be harvested more often