Strategies for Enhancement in Food Reproduction — BIOLOGY STD 12 Science — Question

Which main technique and instrument is used to isolate DNA from any plant cell?

Khorana and his colleagues synthesized an RNA molecule with repeating sequence of AG nitrogenous bases (AG AG AG AG AG AG). It produced a tetrapeptide with alternating sequence of valine and tyrosine. It proves that codon for valine and tyrosine are?

If the surgeon forgets to tide the vas deferens of right side while performing the tubectomy what will be its effect on sterilization?

Name the causative organism of following diseases:

1. Typhoid.
2. Pneumonia.
3. Cold.
4. Ringworm.

What are fossils?

How many pollen grains and ovules are likely to be formed in the anther and the ovary of an angiosperm bearing 25 microspore mother cells and 25 megaspore mother cells respectively?

In Drosophila with 2n = 8, how many linkage groups are present in it?

What is the significance of the zygote formed as a result of sexual reproduction?

Sperms have a tail whereas egg does not, why?