When a snapdragon plant bearing pink colour flower was selfed, it was found that, 69 plants were having red coloured flowers. What would be the number of plants bearing pink flower and white flower? Show with the help of Punnett square. Identity the principle of inheritance involved in this experiment.

Give reason:

(a) A liverwort plant is unable to complete its life cycle in a dry environment.

(b) Number of male gametes produced is much more than the female gametes produced.

(c) Organisms exhibiting external fertilization show great synchrony between the sexes and release a large number of gametes into surrounding medium.

(a) Name the different gases contained in the flask used as an experimental setup by S.L. Miller.

(b) On the basis of composition of gases in this experiment, what was the condition in the flask?

(c) Write the conclusion drawn from this experiment.

Refer to the figure given below and answer the questions that follow:

(a) Explain the process by which Tasmanian wolf evolved.

(b) Name the process that has resulted in evolution of wolf and Tasmanian wolf.

(c) Compare and contrast the two animals shown?

Your classmate complains of headache and cough. On the basis of certain symptoms, the doctor confirms that he is suffering from Pneumonia and not common cold. List these symptoms. Mention any two precautions to be followed to prevent the spread of this disease.