Biotechnology: Principles and Processes — BIOLOGY STD 12 Science — Question

How is a nitrogen base attached to the pentose sugar in a nucleoside?

What makes the Nucleopolyhedrovirus a desirable biological control agent?

OR

 What is the significance of Nucleopolyhedrovirus in pest management?

Name the property of DNA that governs transcription.

What is lactational amenorrhea ?

Spermatids possess haploid chromosome number. Explain.

How is a primary spermatocyte different from a secondary spermatocyte?

In the pie chart (A) and (B) drawn below to show the global animal diversity, which group of animals would you name and write on the areas shaded back in (A) and (B). In which kind of habitat would you find these groups of animals?

When a tall pea plant was self-pollinated, one-fourth of the progeny were dwarf. Give the genotype of the parent and the dwarf progenies.

Name the interaction that exists between Cuscula and shoe-flower plant.

OR

State the type of interaction that exists between ticks and dogs.

Crystals of Bt toxin produced by some bacteria do not kill the bacteria themselves because –

1. Bacteria are resistant to the toxin.
2. Toxin is immature.
3. Toxin is inactive.
4. Bacteria encloses toxin in a special sac.