Which of the following plants is able to show rolling of leaf during the middle of the day?

Match the partial pressure of carbon dioxide in different parts involved in diffusion in comparison to the atmosphere.

Column-$I$	Column-$II$ ($mm\, Hg$ pressure)
$P$. Atmospheric air	$I$. $40$
$Q$. Tissues	$II$. $45$
$R$. Oxygenated blood	$III$. $0.3$

Which of the following plants possesses sunken stomata?

What does abdominal breathing indicate?

Arrange the given steps of the respiration mechanism in the order they occur in the human body:
$I.$ Breathing or pulmonary ventilation
$II.$ Diffusion of $O_2$ and $CO_2$ between blood and tissues
$III.$ Transport of gases by blood
$IV.$ Utilisation of $O_2$ by cells
$V.$ Diffusion of $O_2$ and $CO_2$ across the alveolar membrane
Choose the correct option.

The number of $RBCs$ in man increases if he lives at a higher altitude; this is because