Write any two limitations of using a Ganong's Potometer to demonstrate the uptake of water.

A teacher drew the diagram of heart on the blackboard and told the students to copy it in their notebooks. Mahesh couldn’t see the diagram clearly as it appeared blurred to him.

(a) Name the defect of the eye Mahesh is suffering from.

(b) Where is the image formed in this defect?

(c) Mahesh consults an eye doctor and is prescribed suitable lenses to correct the defect. Which type of lens do his spectacles have?

Name the mineral elements required for:

(a) Clotting of blood

(b) Synthesis of thyroxine

Mention two harmful effects of noise pollution.