Photosynthesis

Question 1

What is photosynthesis and where does it take place?

Answer 1

Uses energy to change carbon dioxide and water into glucose and oxygen.
Takes place in chloroplasts, which contain chlorophyll which absorbs light for photosynthesis.

Question 2

What type of reaction in photosynthesis?

Answer 2

Endothermic, this means energy is transferred from the environment.

Question 3

Word equation for photosynthesis?

Answer 3

Carbon dioxide + water (arrow) glucose + oxygen

Question 4

Symbol equation for photosynthesis

Answer 4

6CO2+6H20(arrow)C6H12O6+6O2

Question 5

Plants use of glucose

Answer 5

1. For respiration
   2.making cellulose - glucose converted to cellulose for making strong cell walls.
2. Making amino acids
3. Stored as oils or fats
4. Stored as starch

Question 6

Limiting factors of photosynthesis

Answer 6

-light
-temperature
-carbon dioxide concentration
-amount of chlorophyll

Question 7

How doers light effect the rate of photosynthesis

Answer 7

• light provides energy for photosynthesis
• as the light level is raised rate of photosynthesis increases steadily, but only up to certain point after that light wont make any difference.

Question 8

How does carbon dioxide concentration affect the rate of photosynthesis?

Answer 8

• co2 is one of the reactant for photosynthesis
• as concentration of co2 rises so will rate of photosynthesis but only up to certain point

Question 9

How does temperature affect rate of photosynthesis?

Answer 9

• temp affects rate of photosynthesis because it affects its enzymes involved.
• as temp increase so will rate of photosynthesis, but if temp gets too high then enzymes needed for photosynthesis will start to denature (normally at about 45 degrees)
  -rate of photosynthesis will start to decrease

Question 10

Give examples of leaf adaptations to maximise photosynthesis

Answer 10

• broad leaves = maximises surface area
• thin leaves = short diffusion path
• veins = transport water to leaves via xyelm, remove photosynthesis products via phloem.
• guard cells = controls opening of stomata for gaseous exchange and prevent water loss.

Question 11

how does amount of chlorophyll affect rate of photosynthesis

Answer 11

decreasing amount of chlorophyll (e.g due to lack of magnesium) decreases rate of photosynthesis because chlorphyll is required to absorb light energy.

Question 12

what is a limiting factor

Answer 12

an environmental factor that can restrict the rate of photosynthesis

Question 13

how can farmers use their knowledge of limiting factors to increase their profits

Answer 13

they can control temp, light intensity and co2 concerntration to acheive the fastest rate of photosynthesis leading to a greater yield

Question 14

state 5 uses of glucose produced from photoshynthesis

Answer 14

-respiration
- starch for storage
- cellulose for strength
- amino acid and protien synthesis (combined with nitrates)
- lipids for energy storage in seeds