Improvement in Food Resources — Science STD 9 — Question

Differentiate between acute and chronic diseases.

A man wearing a bullet-proof vest stands still on roller skates. The total mass is 80kg. A bullet of mass 20 grams is fired at 400m/s. It is stopped by the vest and falls to the ground. What is then the velocity of the man?

It was diagnosed that the body of a patient has lost its power of fighting any infection. Name the disease he is suffering from. What type of microbe is responsible for this disease and how does it spread from one person to the other.

1. Atomic number.
2. Mass number.
3. Valency.

Name any three water pollutants.

Name the following:

1. Smallest cell organelle.
2. Largest cell organelle.
3. ER studded with ribosomes.
4. Functional segments of the DNA molecule.