Hari is fond of watching the fish in an aquarium. So, he set up an aquarium in his house. Along with a number of fresh water fish, he also placed a clown fish which is a salt water fish. After few hours, the clown fish was found dead and floating on water. This was due to:

1. Endosmosis
2. Exosmosis
3. Osmoregulation
4. Excretion

The solvent used for dissolving chlorophyll while testing a leaf for starch is:

1. Sodium hydroxide
2. Lime water
3. Water
4. Ethyl alcohol

A sequence of DNA has 200 nitrogenous base pairs, of which 100 are Thymine-Adenine pairs. What is the number of Cytosine-Guanine pairs in this sequence:

1. 50
2. 200
3. 100
4. 25

The stress hormone in plants which functions during a drought is:

1. Auxins
2. Abscisic acid
3. Ethylene
4. Cytokinins