Absorption by Roots — Biology STD 10 — Question

A potted plant was taken in order to prove a factor necessary for photosynthesis. The potted plant was kept in the dark for 24 hours. One of the leaves was covered with black paper in the centre. The potted plant was then placed in sunlight for a few hours.
Why was the plant placed in the dark before beginning the experiment?

Name the Following
Number of chambers present in the human heart.

What factors govern the growth of population.

Give Technical Terms: The technical term used for the difference between birth rate and death rate in population.

Write down the functional activity of the following parts,
Henle's loop ………………

The source of oxygen during photosynthesis

Mention the contribution of the scientist given below in the study of chromosome:
Sutton and Boveri

Explain the Terms: Death rate

Name the Following :
A specific part of chromosome that determines hereditary characteristics.

Name the Following
The fine blood vessels in the tissues through which exchange of materials occurs