Reproductive Health — BIOLOGY STD 12 Science — Question

Pigs are regarded as the most suitable animals to be bred for heart transplant.

With the help of graphical illustration only, show the changes in the levels of the pituitary hormones during a menstrual cycle.

Answer the following questions:
What are biopesticides? Give any two examples of their application.

Why is that once a person starts taking alcohol or drugs, it is difficult to get rid of this habit? Discuss it with your teacher.

What is the 'wise use concept of Ramsar Convention? Name four types of wetlands included in its mission.

1. Name the causative agent of amoebiasis and mention its symptoms.
2. Write how it spreads.

OR
A patient is down with Amoebiasis. List the symptoms that confirm this infection. Name the causative pathogen.

1. It is generally observed that the children who had suffered from chicken - pox in their childhood may not contract the same disease in their adulthood. Explain giving reasons the basis of such an immunity in an individual. Name this kind of immunity.
2. What are interferons? Mention their role.

Amazonian rain forest has the greatest biodiversity on earth. List any two hypothesis that are proposed by the biologists to account for the greater biological diversity.

Why should biodiversity be conserved? Explain giving three reasons.

Study the graph given below and answer the questions that follow:

1. What is the relationship between dissolved oxygen and biochemical oxygen demand (BOD)?
2. Mention their effect on aquatic life in the river.