Human Reproduction — BIOLOGY STD 12 Science — Question

"Post-industrialization, the population of melanised moth increased in England at the expense of white-winged moths." Provide explanations.

Illustrate the chart of replication of retrovirus.

Write a short note on Double fertilisation.

How do antibiotic-resistance genes function as selectable markers? Explain with the help of E.coli cloning vector pBR 322.

Draw a schematic transverse section of a mature anther of an angiosperm. Label its epidermis, middle layers, tapetum, endothecium, sporogenous tissue and the connective.

The rate of decomposition of detritus is affected by the abiotic factors like availability of oxygen, pH of the soil substratum, temperature etc. Discuss.

Plasmodium falciparum is the causative agent of the most severe form of malaria. It is distributed throughout the tropics. Explain why malaria is restricted to the tropics?

Reproductive and Child Healthcare (RCH) programmes are currently in operation. One of the major tasks of these programmes is to create awareness amongst people about the wide range of reproduction related aspects. As this is important and essential for building a reproductively healthy society.

1. 'Providing sex education in schools is one of the way to meet this goal'. Give four points in support of your opinion regarding this statement.
2. List any two 'indicators' that indicate a reproductively healthy society.

Mention the prevention and control efforts by the population to prevent and control several infectious diseases? How can prevention and control of infectious diseases be done?

Make a list of any three outbreeding devices that flowering plants have developed and explain how they help to encourage cross-pollination.