Human Health and Disease — BIOLOGY STD 12 Science — Question

Trace the development of female gametophyte (embryo sac) from megaspore mother cell in a flower. Give a labelled diagram of the final stage of female gametophyte.

Why is pedigree analysis done in the study of human genetics? State the conclusions that can be drawn from it.

Explain the post-transcriptional modifications, the hnRNA undergoes in eukaryotic cells.

A doctor prescribed morphine as a sedative and pain killer to your cousin who had undergone surgery. Even after recovery, he craved for the prescribed medicine. What do you conclude about his condition, had he continued with the same medication? After appraising yourself, what measures will you suggest to him to overcome this problem? Briefly explain any two.

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 ways 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.

DNA being hydrophilic, cannot pass through the cell membrane of a host cell. Explain how the recombinant DNA gets introduced into the host cellto transform the latter.

What do you understand by sertoli cells? What is their functions?

How do initiation and termination of translation processes occur in bacteria? Where are untranslated regions located in an mRNA? Mention their role.

Name the special type of tissue enabling plants like lotus and water hyacinth to survive in aquatic environment. Mention any two specific functions of this tissue?

ATGGAGTACTTCGTGTGA is the coding strand of DNA in a transcription unit.

1. Write the mRNA transcribed from this DNA segment.
2. How many amino acids does it code for? Why?