Question

Qus: 7) Explain given points with the context of respiration and transportation: [2]
a) What type of arrangement exists in the bodies of large animals to meet their oxygen
requirement adequately?
b) How do the guard cells regulate opening and closing of stomatal pores?​

Answer 1

The explanation follows:

Explanation:

1. The bodies of large mammals have a well evolved and highly complex organ for respiration i.e. lungs. Through nostrils air is taken in and provided passage through bronchus to lungs .The lungs continuously expand and contract through movement of the diaphragm. This air is then goes to bronchi from where it goes inside alveoli .Alveoli are air sacs that are attached to a good network of veins which are filled with blood .The hemoglobin present in blood picks up oxygen from air and circulates it inside the body and carbon dioxide is passed to alveoli which then allows upward movement of this gas and when we exhale this byproduct gets out of our system.
2. Guard cells control opening and closing of stomata through water movement. Whenever water flows inside ,they swell up and curved surfaces cause opening of stomata and when they lose water these shrink and opening is closed.