Ribulose 5 phosphate is a five carbon compound which accepts atmospheric $\mathrm{CO}_2$ in presence of RuBisCo and form 2 molecules of 3PGA, a ${ }^{30}$ carbon compound. It uses 3 ÃTP and 2 NADPH to fix one molecule of $\mathrm{CO}_2$ per cycle of Calvin.
So, to fix $6 \mathrm{CO}_2$ molecules to form 6 carbon compound glucose 6 cycles are required as mentioned below.
| In | Out |
|---|---|
| $\mathrm{Six} \mathrm{CO}_2$ | One glucose molecule $\left(\mathrm{C}_6 \mathrm{H}_{12} \mathrm{O}_6\right)$ |
| 18 ATP | 18 ADP |
| 12 NADPH | 12 NADP |
Complete the flow chart for cyclic photophosphorylation of the photosystem-I.
The following flow chart show cyclic photophosphorylation and the missing part of this flow chart are
Kranz anatomy refers to the dimorphism in the chloroplast structure. It is found in $\mathrm{C}_4$ plants. The cells of leaves have two types of chloroplast in them.
Granal Chloroplast It is found in the mesophyll cells of leaves. Chloroplast have well developed grana in them. These chloroplast effectively fix $\mathrm{CO}_2$ even if it is present in lower concentrations. PEP carboxylase is present which fix $\mathrm{CO}_2$ and to form oxaloacetic acid (4 carbon compound).
Agranal Chloroplast Present in bundle sheath cells of the leaves. $\mathrm{C}_3$ cycle occurs in these cells with the presence of RuBisCo enzyme.
The $\mathrm{C}_4$ plants are well adapted to high $\mathrm{O}_2$ concentrations and high temperature.
$\mathrm{C}_4$ plants can absorb $\mathrm{CO}_2$ even when $\mathrm{CO}_2$ concentration in much low thus $\mathrm{C}_4$ plants can perform high rate of photosynthesis even the stomata are closed or there is the shortage of water thus, they can conserve water.
Since, PEP-carboxylase is insensitive to $\mathrm{O}_2$ thus excess $\mathrm{O}_2$ has us inhibitory effect in $\mathrm{C}_4$ pathway and there is no photosynthesis in $\mathrm{C}_4$ plant.
Thus, $\mathrm{C}_4$ plants are better adapted to tropical and desert (hot acid habitats) areas than the plants, that lack this anatomy.
A process is occurring throughout the day, in ' $X$ ' organism. Cells are participating in this process. During this process ATP, $\mathrm{CO}_2$ and water are evolved. It is not a light dependent process.
(a) Name the process.
(b) Is it a catabolic or an anabolic process?
(c) What could be the raw material of this process?
(a) The name of the process is cellular respiration.
(b) It is a catabolic process which involves break down of glucose molecule.
$$\underset{\text { Carbohydrate + oxygen }}{\mathrm{C}_6 \mathrm{H}_{12} \mathrm{O}_6}+6 \mathrm{O}_2 \longrightarrow \underset{\text { carbon dioxide + water + (ATP) }}{6 \mathrm{CO}_2+6 \mathrm{H}_2 \mathrm{O}+\text { Energy }}$$
(c) Raw material for this process is glucose molecule and oxygen, which are products of photosynthesis, occurring in plants.