Page 105 - Science Class 07

Aim : To count pulse rate of a newly born baby, a child and an adult.
Method : Place your index finger of your right hand on the inner side of the le hand wrist of
baby and count the pulse for a minute. Note it down and do the same ac vity with a child and
adult. Now, try to find the difference in pulse rate of these three persons.

Pulse rate of the infant = _____________________________

Pulse rate of the child = _____________________________
Pulse rate of the adult = _____________________________

1. What is the circulatory medium in human body?
2. What does blood of human beings contain?
3. Where WBC are produced in our body?

4. What is atrium?
5. What is the func on of veins?
6. What is pulmonary circula on of blood?

CIRCULATORY SYSTEM IN OTHER ANIMALS In small and simple mul cellular organisms like
As you know circula on is the process by which sponges, jelly fish, hydra, etc., water circulates
nutrients, respiratory gases and waste products from surrounding medium through certain
are transported inside the body of all kinds of channels in their bodies. Cell in contact with
living organisms. the water take up food and oxygen directly
from it.
In unicellular organisms like amoeba, simple
diffusion across the cell membrane is sufficient
to transport oxygen and carbon dioxide. A
streaming movement of the cell substance
(cytoplasm), called cyclosis, is sufficient to
conduct large molecules like sugar, fats and
proteins to different parts of the cell.

Jelly Fish Hydra

Earthworms have a well-developed circulatory
system. It consists of a network of blood vessel
which is in contact with almost all cells of the
body. Blood is also present inside the tubes in

earthworms consists of mainly water with
dissolved substances and a pigment called

Science-7 105