Molecular Basis of Inheritance — BIOLOGY STD 12 Science — Question

Using Punnett square demonstrate the law of independent assortment in a dihybrid cross involving two heterozygous parents.

1. Differentiate between: Autogamy, Geitonogamy and Xenogamy.
2. Explain the events that occur during pollen-pistil interaction.

What could be the connecting points between the GFC and DFC?

Smita was working in a garage with the doors closed and automobiles engine running. After some time she felt breathless and fainted. What would be the reason? How can she be treated
OR
While working with the car engine in a closed garage, John suddenly felt dizzy and fainted what is the possible reason?

Write about laboratory diagnosis and treatment of AIDS.

Study the flow chart given below. Name the hormones involved at each stage and explain their role.

Write the names of hormones and the glands secreting them for the regulation of following functions
(a) Growth of thyroid and secretion of thyroxine.
(b) Helps in relaxing pubic ligaments to facilitate easy birth of young ones.
(c) Stimulate intestinal glands to secrete intestinal juice.
(d) Controls calcium level in the blood.
(e) Controls tubular absorption of water in kidneys.
(f) Urinary elimination of water.
(g) Sodium and potassium ion metabolism.
(h) Basal Metabolic rate.
(I) Uterine contraction.
(j) Heartbeat and blood pressure.
(k) Secretion of growth hormone.
(l) Maturation of Graafian follicle.

What are the various ways in which mosquitoes can be eradicated from any area?

1. Draw the pyramids of biomass in a pond and in a forest. Explain giving reasons why the two pyramids are different.
2. Pyramid of energy is always upright. Explain.

What is cancer? Differentiate between benign tumour and malignant tumour. The main five types of cancer