Consider the structures of the three cyclic carbon compounds A, B and C given below and select the correct option from the following:

1. A and C are isomers of hexane and B is benzene.
2. A is an isomer of hexane, B is benzene and C is an isomer of hexene.
3. A is a saturated cyclic hydrocarbon and B and C are unsaturated cyclic hydrocarbons.
4. A is cyclohexane and B and C are the isomers of benzene.

The statement that correctly describes the characteristic(s) of a gene is :

1. In individuals of a given species, a specific gene is located on a particular chromosome.
2. A gene is not the information source for making proteins in the cell.
3. Each chromosome has only one gene located all along its length.
4. All the inherited traits in human beings are not controlled by genes.

Consider the following statements about small intestine and select the one which is NOT correct :

1. The length of the small intestine in animals differs as it depends on the type of food they eat.
2. The small intestine is the site of complete digestion of food.
3. The small intestine receives secretions from liver and pancreas.
4. The villi of the small intestine absorbs water from the unabsorbed food before it gets removed from the body via the anus.

Select washing soda from the following :

1. NaHCO₃
2. Na₂CO₃.5H₂O
3. Na₂CO₃.10H₂O
4. NaOH