Human Reproduction — BIOLOGY STD 12 Science — Question

Explain the law of segregation with any one example.

Name the enzyme produced by Streptococcus bacterium. Explain its importance in medical sciences.

Collect 5 examples of palindromic DNA sequences by consulting your teacher. Better try to create a palindromic sequence by following base-pair rules.

Explain what happens in frameshift mutation. Name one disease caused by the disorder.

Enumerate the symptoms of common cold. Name the category of the organism causing it.

Draw a labelled diagram of sperm.

Two independent monohybrid crosses were carried out involving a tall pea plant with a dwarf pea plant. In the first cross, the offspring population had equal number of tall and dwarf plants, whereas in the second cross it was different. Work out the crosses, and explain giving reasons for the difference in the offspring populations.

OR

Work out a cross to find the genotype of a tall pea plant. Name the type of cross.

Both haemophilia and thalassemia are blood related disorders in humans. Write their causes and the difference between the two. Name the category of genetic disorder they both come under.

Mention the factors on which the nature/ type of pioneer species of a secondary succession depend.

Name two hormones that are constituents of contraceptive pills. Why do they have high and effective contraceptive value? Name a commonly prescribed non-steroidal oral pill.