Ecosystems — BIOLOGY STD 12 Science — Question

Study the given flow chart and answer:

1. Name the defence mechanism used.
2. In which plant it has been done?
3. Name the pathogen.
4. Name the vector used in this technique.

What are antibiotics? Name the classes of organisms that produce antibiotics

Name the embryonic stage that gets implanted in the uterine wall of a human female.

Study the graphical representation of Species richness - Area relationship given below and answer the questions that follow:

a. What do S, C, Z and A represent in the given graph?
b. What will be the range value of Z line if we analyse the species-area relationship among very large areas like entire continent?

A non biology person is quite shocked to know that apple is a false fruit, mango is a true fruit and banana is a seedless fruit. As a biology student how would you satisfy this person.

1. Give one example each of albuminous and non albuminous seeds.
2. Name the parts of the ovule and the embryo sac of an angiosperm that develop into.

1. Perisperm.
2. Seed coat.
3. Endosperm, and.
4. Embryonal axis.

Name the stage ofthe Plasmodium thall is trrnsmitted to human body by the vector. Describe the life cycle of the plrasite in humans.

OR

Trace the life cycle of Plasmodium in humans from the stage of entry, until it is picked up by the female Anopheles.

Explain : PCR

Mention the name of the causal organism, symptoms and the mode of transmission of the disease Amoebiasis.

Observe the diagram for genetic mapping of human DNA and answer the following questions:

i. Explain DNA polymorphism as the basis of genetic mapping of the human genome.
ii. State the role of VNTR in DNA fingerprinting.