Which of the following two changes occur in humans when they move to high altitudes (above $3,500 \ m$)?
$(1)$ Increase in red blood cell size
$(2)$ Increase in red blood cell production
$(3)$ Increase in breathing rate
$(4)$ Increase in thrombocyte count

In most of the thin-leaf mesophytes,the leaf stomata open during the day and close during the night. This pattern is known as:

Select the correct option:
$(1)$ The respiratory rhythm center for breathing regulation is located in the medulla oblongata of the brain.
$(2)$ Each hemoglobin molecule can carry a maximum of $4$ molecules of $O_2$. (Note: The original question mentioned $CO_2$,which is incorrect; hemoglobin primarily transports $O_2$.)

Assertion: In mammals,a complex respiratory system has developed.
Reason: Mammalian skin is impermeable to gases.

What is the respiratory rate in a rabbit?

Find out the false statement.