Difference between C3, C4 and CAM Cycle

Q.

Some photosynthetic organisms contain chloroplasts that lack photosystem II, yet are able to survive. The best way to detect the lack of photosystem II in these organisms would be

1. to determine if they have thylakoids in the chloroplasts.

2. to test for liberation of O2 in the light.

3. to test for CO2 fixation in the dark.

4. to do experiments to generate an action spectrum

Q.

Consider the following statements regarding photosynthesis:

A. ATP formation during photosynthesis is termed photophosphorylation.

B. Kranz anatomy pertains to leaf.

C. Reduction of NADP⁺ to NADPH occurs during the Calvin cycle.

D. In a chlorophyll molecule, magnesium is present in the phytol tail

Of the above statements,

1. A and B are correct.

2. C and D are correct.

3. A and C are correct.

4. B and C are correct.

5. A and D are correct.

Q.

The immediate products of C3 and C4 photosynthesis are, respectfully:

1. ribulose 1, 5-bisphosphate; malic acid

2. malate; carbon dioxide

3. glyceraldehyde 3-phosphate; phospho-enol-pyruvate (PEP)

4. 3-phosphoglycerate; oxaloacetic acid

Q. What is the difference between c2 cycle and photorespiration?

Q. The most important difference between $C_3$ and $C_4$ plants is ___________.

1. respiration
2. photorespiration
3. Calvin cycle
4. glycolysis cycle

Q. A process that makes important difference between $C_3$ and $C_4$ plants is

1. Photosynthesis
2. Photorespiration
3. Transpiration
4. Glycolysis

Q. C₄ plants are more efficient in photosynthesis than C₃ plants due to

1. Higher leaf area
2. Presence of larger number of chloroplasts
3. Presence of cuticle
4. Lower rate of photorespiration

Q.

How many ATP molecules are formed during Krebs cycle?

Q. In comparison to the $C_3$ plant, which of the following is true for ${\mathrm{CO}}_2$ compensation point of $C_4$?

1. $C_4$ plants will have a lower ${\mathrm{CO}}_2$ compensation point
2. $C_4$ plants will have a higher ${\mathrm{CO}}_2$ compensation point
3. $C_4$ plants require higher ${\mathrm{CO}}_2$ concentration to reach the compensation point
4. $C_3$ plants require lower ${\mathrm{CO}}_2$ concentration to reach the compensation point

Q.

By looking at which internal structure of a plant can we tell whether a plant is C3 or C4?

Q. At low $C{O}_2$ concentration, photorespiration in $C_3$ and $C_4$ plants respectively is

1. high, high
2. low, medium
3. high, negligible
4. negligible, high

Q. A plant in your garden avoids photorespiratory losses, has improved water use efficiency, shows high rates of photosynthesis during daytime and has improved efficiency of nitrogen utilization. In which of the following physiological groups would you assign this plant?

1. $C_3$
2. $C_4$
3. Both $C_3$ and $C_4$
4. $Nitrogenfixer$

Q. With reference to factors affecting the rate of photosynthesis, which of the following statement is not correct?

1. Increasing atmospheric${\mathrm{CO}}_2$ concentration up to 0.05% can enhance ${\mathrm{CO}}_2$ fixation rate
2. $C_3$ plants respond to higher temperature with enhanced photosynthesis while $C_4$ plants have much lower optimum temperature
3. Tomato is a greenhouse crop which can be grown in ${\mathrm{CO}}_2$- enriched atmosphere for higher yield
4. Light saturation for ${\mathrm{CO}}_2$ fixation occurs at 10% of full sunlight

Q. Which one is the same between a $C_4$ and a $\mathrm{CAM}$ plant?
I. Leaf anatomy
II. Enzyme catalyzing reaction that fixes ${\mathrm{CO}}_2$
III. Presence of Calvin cycle
IV. Location of $\mathrm{PEP}\mathrm{carboxylase}$ and $\mathrm{RuBisCO}$ in the leaf

1. Only II
2. Only II and III
3. I and II
4. III and IV

Q.

photosynthesis because it

1. Is degraded very rapidly

2. Also acts as an oxygenase

3. Catalyses a reversible reaction

4. Is a very slow-acting enzyme

Q. Match the column-I with column-II.
$\begin{array}{cccc}& \text{Column-I}& & \text{Column-II}\\ \text{(a)}& C_4\text{Cycle}& \left(1\right)& \text{Photorespiration}\\ \text{(b)}& C_3\text{Cycle}& \left(2\right)& \text{Kreb's Cycle}\\ \text{(c)}& C_2\text{Cycle}& \left(3\right)& \text{Hatch and Slack pathway}\\ \text{(d)}& \text{TCA Cycle}& \left(4\right)& \text{Calvin and Benson pathway}\end{array}$

1. a - (4); b - (2); c - (1); d - (3)
2. a - (1); b - (2); c - (3); d - (4)
3. a - (3); b - (2); c - (1); d - (4)
4. a - (3); b - (4); c - (1); d - (2)

Q.

photorespirations is same as calvin cycle??

Q.

Why is thecolour of a leaf kept in the dark frequently yellow, or pale green?Which pigment do you think is more stable?