BIOLOGY 3 Marks Question

A = +
B = +
C = Competition
D = +
E = -
F Commensalism

i. Endemism: These are the species which are confined to a particular geographical region and they are not found anywhere else. Such species are called endemic species.
ii. Four regions in and around our country that are considered hot-spots are
a. Western Ghats
b. Himalaya
c. Indo-Burma
d. Sri Lank

a. Gene therapy can be used for the treatment of the child with ADA deficiency. In this method, the lymphocytes from the blood of the patient are grown in a culture outside the body. A functional ADA CDNA is introduced into these lymphocytes using a retroviral vector. These lymphocytes are then returned to the patient. If the gene isolated from marrow cells producing ADA is introduced into cells at early embryonic stage, then it can be a permanent cure.
b. Other possible methods for curing ADA deficiency disease Bone marrow transplantation and enzyme replacement therapy (giving the functional enzyme to the patient by injection).

Charles Darwin formulated the theory of natural selection.
Differential reproduction means that some members of a population have traits that enable them to grow up and reproduce at a higher rate and leave more surviving offspring in the next generation than others. If it continues for many generations genes of the individuals, which produce more offspring will become more predominant in the gene pool of population.

In enzyme replacement therapy, the patient is given functional ADA (Adenosine Desaminase) by injection.
Hereditary disease can be corrected by gene therapy. It is a collection of methods that allows correction or replacement of defective genes. The first gene therapy was given in 1990 to a 4 years old girl with Adenosine Deaminase (ADA) deficiency. It is caused due to the deletion of gene for adenosine deaminase.
Disadvantage
i. The patient does not completely recover from the disease.
ii. It needs periodic injections of the enzyme to the patients.

I. Transcription unit

Pea is a annual plant which gives result within a year. Large number of seeds are produced by pea plant in one generation. Pea plant has short life cycle. A large number of true breeding varieties with observable alternative forms for a trait were available.

In situ conservation - conservation and protection of whole ecosystem and its biodiversity at all levels in their natural habitat.
Whereas Ex situ conservation involves taking out the threatened animals and plants from their natural habitat and placed in special settings where they can be protected and given special care.