Human Health and Disease — BIOLOGY STD 12 Science — Question

Explain the components of Ecosystem.###What do you understand by an ecosystem? Describe the structure and components of an ecosystem.

Can you list 10 recombinant proteins which are used in medical practice? Find out where they are used as therapeutics (use the internet).

Describe the molecular structure of DNA by making a labelled diagram.

During the course of evolution why DNA was chosen over RNA as genetic material? Give reasons by first discussing the desired criteria in a molecule that can act as genetic material and in the light of biochemical differences between DNA and RNA.

The biology teacher asked her students to verify the experiment on transformation principle in bacteria to establish DNA as genetic material. The class was divided into two groups. The teacher asked them to submit the reports. Group 2 did not use mouse and did not repeat Griffith's experiment. The teacher praised them.

1. Which experiment did they perform?
2. Explain the experiment in brief.
3. Who and when performed the transformation principle experiment?
4. What values did students of group 2 exhibit?

Draw a labelled diagram of the sectional view of a mature pollen grain in angiosperms. Explain the functions of its different parts.

Draw a diagrammatic sketch of the sectional view of a typical anatropous ovule.

OR

Draw a labelled diagram of the sectional view of a typical anatropous ovule.

Restriction enzymes are found in bacteria (and other prokaryotes). They recognize and bind to specific sequences of DNA, called restriction sites. Each restriction enzyme recognizes just one or a few restriction sites.
When it finds its target sequence, a restriction enzyme will make a double-stranded cut in the DNA molecule.
i. Write the palindromic nucleotide sequence for the following DNA segment.
5'-GAATTC-3'
ii. Name the restriction endonuclease that recognises this sequence.
iii. How are sticky ends produced? Mention their role.

Write the sequence of steps involved in the sequencing of genome of an organism.

How are DNA molecule replicate? Describe it.###Describe the process of DNA replication.