Hiccups can be best described as

Choose the correct option:
$(1)$ The volume of gases involved in breathing movements is measured by $Sphygmomanometer / Spirometer$.
$(2)$ Inspiration is initiated by the $relaxation / contraction$ of the diaphragm.

During respiration,if the volume of the thoracic cavity of a rabbit is maximum,then:

What is the cause of altitude sickness?

Expiration occurs only when.....

Select the correct process that occurs during inspiration (inhalation):
$(a)$ Contraction of the diaphragm
$(b)$ Contraction of external intercostal muscles
$(c)$ Decrease in pulmonary volume
$(d)$ Increase in intra-pulmonary pressure