Answer:
ai) P= Red blood cell Q= Alveoli
ii)1. It gives the lungs a large surface area to volume ratio.
2. It is moist and thin.
b) P has a disc or biconcave shape which allows the O2 to bind to it with the help of a protein called haemoglobin for it to be transferred to various parts of the body.
c) Carbon monoxide will bind to the haemoglobin to form carboxyhaemoglobin causing oxygen disruption
Answer:
They tend to move away from any stimulus be it light or mechanical.
Explanation:
The earthworm, upon encountering a stimulus that is mechanical in nature will turn its anterior end slightly away from the stimulus. Persistence of the stimulus may cause the worm to contract the longitudinal muscles of the opposite side to move the body around taking a new direction. And they also have the behaviour of tending to move away from any light stimulus.
Answer:
They are classified into three orders: frogs and toads, salamanders and newts, and caecilians.
Answer:
The living organisms in the environment consists of all the organisms on planet Earth and the areas where they live. Population. Consists of organisms of the same species that live in the same area and interact with one another.