Write the names of the parts labeled as A, B, C, D in the diagram given below:

(a) State two main reasons for carbon forming a very large number of compounds.

(b) Give a reason why carbon forms compound

(i) Namely by Covalent bonding

(ii) Having low melting and boiling points

(c) What happens when (Write chemical equations of the reactions)

(i) A piece of sodium metal is added to ethanol.

(ii) Ethanoic acid reacts with sodium hydroxide.

Draw a longitudinal section of a flower and label the following parts –

(a) Part that develops into a fruit

(b) Part that produces pollen grain

(c) Part that transfers male gametes

(d) Part that is sticky to trap.

(a) How does speciation take place?

(b) Define the term GENE.

(c) The gene for red hair is recessive to the gene for black hair. What will be the hair colour of a child if he inherits a gene for red colour from his mother and a gene for black hair from his father? Express with the help of flow chart.

Explain the formation of rainbow in the sky with the help of a diagram. List the three phenomena of light involved. Which colour – violet or red appears at top of the rainbow?