31.

Explain the C₄ cycle of photosynthesis.

(a) Differentiate between apes and man with respect to the following characteristics: (i) Posture (ii) Cranium (iii) Brow ridges (iv) Locomotion

b) Define:

(i) Vestigeal organs

(ii) Variations

(iii) Neo–Darwinism

(a) State four characteristics of the Cromagnon man.

(b) Explain the basic postulates of Darwinism.

(c) Archaeopteryx is a connecting link between reptiles and birds. Justify the statement by giving two characteristics of each group.

(a) Persons suffering from G6PD deficiency are resistant to malaria. Explain.

(b) Define:

(i) Genetic Erosion    (ii) Bioinsecticides (iii) Antigen (iv) Psychosis

(c) Define Biofortification.

(a) List the activities of Community Health Services.

(b) Give three early diagnostic symptoms of cancer.

(c) Define: (i) Carrying capacity (ii) Implant (iii) Carcinoma

(a) Give four differences between root apex and shoot apex.

(b) Explain the development of the different types of endosperms in angiosperms.

(c) Explain briefly: (i) Capillary water (ii) Osmosis (iii) Aeroponics

(a) Mention one role and one deficiency symptom of the following elements in plant nutrition:

(i) Phosphorus (ii) Iron (iii) Chlorine

State the advantages and disadvantages of vegetative reproduction.

(a) What are tropic hormones ? Describe the feedback control of tropic hormones with an example.

(b) Explain the conduction of nerve impulse through a nerve fibre.

(c) Draw a labelled diagram of the T.S. of bone.