Microbes in Human Welfare — BIOLOGY STD 12 Science — Question

What is common about Eichhornia, Lantana and Parthenium with reference to threat to our biodiversity?

The chances of conception are nil during lactational amennorrhea method. Why?

The meiocyte of rice has 24 chromosomes. Write the number of chromosomes in its endosperm.

Cows and dogs are eurythermal animals. Why are polar bears categorised as stenothermal animals? Give one reason.

Give a schematic representation of oogenesis in humans, Mention the number of chromosomes at each stage. Correlate the life phases of the individual with the stage of the process.

Mark the odd one in give each of the following groups.
Lamarckism, Darwinism, Branching descent, Natural selection.

Under what conditions would a particular stage in the process of succession revert back to an earlier stage?

Name the causative organism of influenza.

Name an example of a rod-shaped virus.

Mention the role of restriction enzymes in recombinant DNA technology.