Q. State Gause's Competitive Exclusion Principle.

Q. Name the vegetative propagates in the following.
(a) Bryophyllum (b) Agave

Q. Name the part of the flower which the tassels of the corn-cob represent.

Q. Describe the mutual relationship between fig tree and wasp and comment on the phenomenon that operates in their relationship.

Q. How have transgenic animals proved to be beneficial in the following application of transgenic?
(a) Production of biological products
(b) Chemical safety testing

Q.

Q. Why are the human testes located outside the abdominal cavity? Name the pouch in which they are present.

Q. Write the scientific name of the fruit-fly. Why did Morgan prefer to work with fruit-flies for his experiments? State any three reasons.

Q. Explain the significant role of the gene nucleopolyhedrovirus in an ecological sensitive area.

Q. Why are analogous structures a result of convergent evolution?

Q. Why is Gambusia introduced into drains and ponds?

Q. Name and describe the technique that helps in separating the DNA fragments formed by the use of restriction endonuclease.

Q. Name the type of association that the genus Glomus exhibits with higher plants.

Q. With advancements in genetics, molecular biology and tissue culture, new traits have been incorporated into crop plants. Explain the main steps in breeding a new genetic variety of a crop.

Q. Since the origin of life on earth, there were five episodes of mass extinction of species.
(i) How is the 'sixth extinction', presently in progress, different from the previous episodes?
(ii) Who is mainly responsible for the 'sixth extinction'?
(iii) List any four points that can help to overcome this disaster.

Q. Construct an age pyramid which reflects an expanding growth status of human population.

Q. How does a restriction nucleases function? Explain.

Q. State the role of C peptide in human insulin.

Q. Why is it not possible for an alien DNA to become part of a chromosome anywhere along its length and replicate normally?

Q. (a) Describe the various steps of Griffith's experiment that led to the conclusion of the 'Transforming Principle'.
(b) How did the chemical nature of the 'Transforming Principle' get established?

Q. The following graph shows the species -area relationship. Answer the following questions as directed.
(a) Name the naturalist who studied the kind of relationship shown in the graph. Write the observations made by him.
(b) Write the situations as discovered by the ecologists when the value of '$Z$' (slope of the line) lies between (i) $0.1$ and $0.2$ (ii) $0.6$ and $1.2$. What does '$Z$' stands for?
(c) When would the slope of the line '$b$' become steeper?

Q. In Snapdragon, a cross between true-breeding red flowered (RR) plants and true-breeding white flowered (rr) plants showed a progeny of plants with all pink flowers.
(a) The appearance of pink flowers is not known as blending. Why?
(b) What is this phenomenon known as?

Q. Why is pedigree analysis done in the study of human genetics? State the conclusions that can be drawn from it.

Q. (a) Where does fertilization occur in humans? Explain the events that occur during this process.
(b) A couple where both husband and wife are producing functional gametes, but the wife is still unable to conceive, is seeking medical aid. Describe any one method that you can suggest to this couple to become happy parents.

Q. Identify 'a', 'b', 'c', 'd', 'e', and 'f' in the table given below:

Q. Make a list of any three out breeding devices that flowering plants have developed and explain how they help to encourage cross-pollination?

Q. State the function of a reservoir in a nutrient cycle. Explain the simplified model of carbon cycle in nature.

Q. Community service department of your school plans a visit to a slum area near the school with an objective to educate the slum dwellers with respect to health and hygiene.
(a) Why is there a need to organise such visits?
(b) Write the steps you will highlight, as a member of this department, in your interaction with them to enable them to lead a healthy life.

Q. List the symptoms of ascariasis. How does a healthy person acquire this infection?

Q. With the help of one example, explain the phenomenon of co-dominance and multiple allelism in human population.