Human Health and Disease — BIOLOGY STD 12 Science — Question

Banana is a parthenocarpic fruit, whereas oranges showpolyembryony. How are they different from each other with respect to seeds?

A3' ............ 5'B
C5’ ........... 3'D.
AB and CD represent two strands of a DNA molecule. When this molecule undergoes replication, forming a replication fork between A and C in the above.

1. Name the templete strand for replication.
2. Using which strand as the templete, will there be continuous synthesis of a complementary DNA strand
3. Complementary to which strand will okazaki segments get synthesised, discontinuous synthesis occurs.
4. What are templete strands and Okazaki pieces?
5. In which direction is a new strand synthesised?

Explain any two methods of vector less gene transfer.

In an artificial hybridisations programme observed events as follows. Rearrange them in collect series as per hysridisation programme.
(a) Re bagging
(b) Choose parents
(c) Bagging
(d) spread pollen on stigma
(e) Emasculation
(f) collect pollen from male parental plant

 In which phase of menstrual cycle is corpus luteum formed?

What is sexually transmitted infection? Give simple principles to control it.

What is Ramsar Convention? How was it called previously?

AUG GAC CUG AUA UUU UGA is the base sequence in a strand of mRNA.

1. Write the base sequence of the DNA strand from which it has been transcribed.
2. Upon translation, how many amino acids will the resulting peptide have?

How many cells are present in the pollen grains at the time of their release from anther? Name the cells.