Microbes in Human Welfare — BIOLOGY STD 12 Science — Question

Give functions : Functions of hormones secreted by the thyroid gland.

1. Write your observations on the variations seen in the Darwin’s finches shown above.
2. How did Darwin explain the existence of different varieties of finches on Galapagos Islands?

Describe the structure of the heart wall.

All animals are called consumers.

How does the transmission of each of the following diseases take place?
(a) Amoebiasis:
(b) Malaria:
(c) Ascariasis:
(d) Pneumonia:

Study a part of the life cycle of malarial parasite given below. Answer the questions that follow:

1. Mention the roles of ‘A’ in the life cycle of the malarial parasite.
2. Name the event ‘C and the organ where this event occurs.
3. Identify the organ ‘B’ and name the cells being released from it.

What is test cross?

Why are farmers and gardeners advised to buy new F1 hybrid seeds every year?

Refer to the diagram given below and answer the questions that follow.

1. The parasite reproduces in human host by which method?
2. The sexual stages of parasite are referred to as?
3. Where does the fertilisation and development of parasite takes place in mosquito body?
4. What are sporozoites?
5. What is the cause of cycles of fever during malaria?

Given below is the representation of amino acid composition of the relevant translated portion of b-chain of haemoglobin, related to the shape of human red blood cells.
Who are likely to suffer more from the defect related to the gene represented the males, the females or both males and females equally? And why?