When the external temperature is higher than our body temperature, we regulate it by $........$, and when it is lower than our body temperature, we regulate it by $........$.

Whales are air-breathers but can live underwater for a long time because they possess:

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.

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

Match List-$I$ with List-$II$.

List-$I$	List-$II$
$A$. Emphysema	$I$. Rapid spasms in muscle due to low $Ca^{++}$ in body fluid
$B$. Angina Pectoris	$II$. Damaged alveolar walls and decreased respiratory surface
$C$. Glomerulonephritis	$III$. Acute chest pain when not enough oxygen is reaching to heart muscle
$D$. Tetany	$IV$. Inflammation of glomeruli of kidney

Choose the correct answer from the options given below:

Mark the incorrect statement.