Reproduction in Lower and Higher Animals — BIOLOGY STD 12 Science — Question

If a father and son are both defective in red-green colour vision, is it likely that the son inherited the trait from his father? Comment.

Sketch and label the dorsal (posterior) view of human heart.

Draw and label the parts of the head region only of a human sperm.

Name the type of curve that characterises most population growing in favourable environment. Also define carrying capacity.

A set of terms are given below (box) followed by few statements in a box.

Outbreeding, Inbreeding, Out-crossing, Cross-breeding, Interspecific hybridisation.

Pick the correct term and write it against the appropriate statement.

1. Male and female animals of two different related species are mated.
2. Superior males of one breed are mated with superior females of another breed.
3. Mating of animals within the same breed, but having no common ancestors on the either side of their pedigree up to 4-6 generations.
4. Mating of more closely related individuals within the same breed for 4-6 generations.

A sperm has just fertilised a human egg in the fallopian tube. Trace the events that the fertilised egg will undergo up to the implantation of the blastocyst in the uterus.

Give any four possible ill effects of contraceptives.

Draw a labelled diagram of t-RNA carrying Glutamic acid.

Nuclein was called as nucleic acid.

Regulation of lac operon can be visualised as regulation of enzyme synthesis by its substrate. Explain the statement.