Sexual Reproduction in Flowering Plants — BIOLOGY STD 12 Science — Question

Name two dominant plant species of mangroves.

Mention the three zones of a biosphere reserve.

What are bioherbicides? Give any two examples.

Draw and label the parts of the only head region of a human sperm.
OR
Draw a well-labelled diagram of a sperm.

What is corpus luteum? Under what conditions does it undergo degeneration?

From what you have learnt, can you tell whether enzymes are bigger or DNA is bigger in molecular size? How did you know?

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.

Which substrates are used for biogas production?

Why the plants that inhabit a desert are not found in a mangrove? Give reasons.

What is protoplast fusion?