Reproductive Health — BIOLOGY STD 12 Science — Question

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.

What do you understand by co-dominance? Explain the co-dominance by taking example of blood group in human.

1. Why must bacterial cells be first made 'competent' in rDNA technology? How is the process carried out?
2. Name the methods by which an alien DNA can be made to enter:

1. A plant cell.
2. An animal cell.

Study the pedigree chart given below, showing the inheritance pattern of blood groups in a family and answer the given questions.

1. Give the possible genotypes of the individuals 1 and 2.
2. Which antigen will be present on the plasma membrane of RBCs of individuals 5 and 9?
3. Give the genotypes of the individuals 3 and 4.

When a cross is made between tall plant with yellow seeds (TtYy) and tall plant with green seeds (Ttyy), what proportions of phenotypes in the offsprings could be expected to be:
(i) tall and green
(ii) dwarf and green

The graph given below shows species-area relationship of a certain region.

a. Study the graph and explain what it represents.
b. After a while, a small area was taken for constructing a road which divided the region into two. Write the impact this construction would have on species richness of the region.

The following illustrates the linking of DNA fragments A DNA fragments:

1. Write the name of A and B.
2. Complete the palindrome, which is recognized by EcoRI.
3. Write the name of the enzyme that can link the two DNA fragments.

‘‘A very small sample of tissue or even a drop of blood can help determine paternity’’. Provide a scientific explanation to substantiate the statement.

Explain the increase in the numbers of melanic (dark winged) moths in the urban areas of post-industrialisation period in England.