Blood

Gametocytes of Plasmodium enter the mosquito’s gut with the blood meal. In the gut, gametocytes develop into gametes, fuse to form zygotes, and subsequently develop into sporozoites. \item The sporozoites migrate to the mosquito’s salivary glands, preparing it to infect another host.

Step 1: Match Bioactive Substances to Their Actions.
Statin: Lowers blood cholesterol (III).
Cyclosporin A: Acts as an immunosuppressive agent (IV).
Streptokinase: Removes clots from blood vessels (II).
Lipase: Removes oil stains (I).
Final Answer: A - III, B - IV, C - II, D - I.

After six generations in a medium with heavy nitrogen ( ), most DNA will incorporate , resulting in heavy DNA.
- The ratio of hybrid to heavy DNA will be 1:31 after centrifugation.
- After six generations in a medium with heavy nitrogen ( ), most DNA will incorporate , resulting in heavy DNA.
- The ratio of hybrid to heavy DNA will be 1:31 after centrifugation.

(a) There are three alleles involved in human ABO blood grouping.

These alleles are:

• I^A – codes for A antigen
• I^B – codes for B antigen
• i – codes for no antigen (O type)

This is an example of multiple alleles, where more than two alleles exist for a genetic trait, but only two are present in an individual at a time.

(b) The inheritance type is called Co-dominance.

In co-dominance, both alleles in a heterozygous individual are fully expressed. In the case of blood group AB:

• The person inherits I^A from one parent and I^B from the other.
• Both A and B antigens are expressed on the surface of red blood cells.

(c) Yes, it is possible for them to have a child with 'O' blood group, depending on their genotypes.

Explanation:

Blood group A can have genotype: I^AI^A or I^Ai
Blood group B can have genotype: I^BI^B or I^Bi

If the man is I^Ai and the woman is I^Bi, the possible cross is:

Conclusion: If both parents are heterozygous (I^Ai and I^Bi), there is a 25% chance that the child may inherit i from both parents and have blood group O (genotype: ii).