Difference between C3, C4 and CAM Cycle

Q. Photorespiration does not occur in $C_4$ plants because

1. of enzyme RuBisCO
2. the first primary acceptor is phosphoenolpyruvate
3. they do not require $C{O}_2$
4. they have a mechanism that increases the concentration of $C{O}_2$ at the enzyme site

Q. Match Column-I with Column-II and select the correct option from the codes given below.
$$\begin{array}{cc}\text{Column - I}& \text{Column - II}\\ A.C_4\text{Plants}& \text{(i) Succulent plants}\\ B.\text{Chlorophyll b}& \text{(ii) Sorghum}\\ C.\text{PS II}& \text{(iii) P-680}\\ D.\text{CAM}& \text{(iv) Accessory photosynthetic pigment}\end{array}$$

1. A-(i), B-(ii), C-(iii), D-(iv)
2. A-(iii), B-(ii), C-(iv), D-(i)
3. A-(i), B-(iii), C-(ii), D-(iv)
4. A-(ii), B-(iv), C-(iii), D-(i)

Q. With reference to factors affecting the rate of photosynthesis, which of the following statements is incorrect?

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

Q. In addition to the $12$ molecules of $NADPH$ the energy required for the synthesis of one mole of hexose by $C_3$ and $C_4$ pathway is

1. 18 molecules of ATP
2. 30 and 18 molecules of ATP respectively
3. 30 molecules of ATP
4. 18 and 30 molecules of ATP respectively

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

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

Q. $C_4$ plants are more efficient in photosynthesis than $C_3$ plants due to:

1. Higher leaf area
2. Presence of large number of chloroplasts in the leaf cells
3. Presence of thin cuticle
4. Lower rate of photorespiration

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

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

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

Q. $C_4$- plants differ from $C_3$-plants in respect to

1. Number of $C{O}_2$ molecules used
2. Substrate, which accept the $C{O}_2$ molecules
3. The final product
4. Number of ATP formed

Q. How does CAM photosynthesis differ from C3 or C4

1. Malic acid is formed at night, stored in vacuoles in cells housing chloroplasts
2. CAM photosynthesis continues at night while C3 and C4 photosynthesis occur during the day
3. CAM photosynthesis extracts carbon from organic compounds
4. CAM plants must use large quantity of water for photosynthesis

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

Q. In $C_4$ plants photorespiration does not occur due to

1. presence of Rubisco enzyme
2. presence of high light intensity
3. increased concentration of $C{O}_2$ at enzyme site
4. presence of bundle sheath cells

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. 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