Photosynthesis - Limiting Factors

Question 1

Minerals needed by photosynthesis

Answer 1

Nitrogen, magnesium, phosphate

Question 2

Magnesium Mg^2+

Answer 2

Function:
Main component in chlorophyll molecular formation
-if none chlorophyll become deactivated

Signs of deficiency:
Chlorosis- yellowing of leaves

Question 3

Nitrate NO3^-

Answer 3

Function:
Component in amino acid (protein synthesis)

Signs of deficiency:
Chlorosis, stunted growth

Question 4

Phosphate PO4^3-

Answer 4

Function:
ATP synthesis, products in light independent reaction (RuBP)

Signs of deficiency:
Dark green leaves, red purple edges

Question 5

How compare plants using positive + negative control

Answer 5

Positive - plant with all needed ions
Negative - no ions
Compare with plants lacking with one type of ions

Question 6

Law of limiting factor

Answer 6

When there are 2 or more limiting factors affect the rate of a reaction, the factors that is nearest to minimum value limits the rate of reaction, and rate only increase if this factor increases

Question 7

Other limiting factors of photosynthesis

Answer 7

Light intensity, CO2 concentration, temperature

Question 8

How light affect photosynthesis

Answer 8

-As light increase, rate of photosynthesis increase (from light dependent reaction)
-more electrons excited = more ATP + NADPH
(On graph it is a straight line increase)

-Further increase reach plateau (CO2 or temp limiting factor)
-if too high, chlorophyll damaged = rate drops

Question 9

How CO2 concentration affect photosynthesis

Answer 9

-CO2 increase = increase light independent rate (more things for RuBP)
-low conc in air (0.04%), so small change = rapid rise
-limited by max rate of fixation (RuBP or rubisco) or other factors

Question 10

How temperature affect photosynthesis

Answer 10

Affect light independent
-more temp = enzyme move faster (rubisco)

Temp to high cause denature = rapid drop in rate

Question 11

Comparing limiting factors

Answer 11

-If light intensity high, co2 + temp limiter
-if co2 high, light + temp limiter
-if light + temp high, co2 limiter

-at low light intensity, increasing temp does not increase rate, but if high light it does increase (shows light dependent reaction is before independent)

-if co2 + temp increasing and light intensity is high, co2 matter more in increase

Question 12

Diagram for comparison

Answer 12

https://microbenotes.com/wp-content/uploads/2022/05/Factor-Affecting-Rate-Of-Photosynthesis-Limiting-Factors.jpeg

Question 13

Diagram of increasing temp under high and low light intensity

Answer 13

https://resource.download.wjec.co.uk/vtc/2020-21/el20-21_1-14/downloads/image_4.png

Question 14

Diagram of comparing co2 + temp

Answer 14

https://resource.download.wjec.co.uk/vtc/2020-21/el20-21_1-14/downloads/image_5.png