Answer:
In immunology, an antigen is a molecule or molecular structure, such as may be present on the outside of a pathogen, that can be bound by an antigen-specific antibody or B-cell antigen receptor. The presence of antigens in the body normally triggers an immune response.
Answer:
For regulating activities of cell.
Explanation:
Ad nucleus consists of genetic materials like DNA,RNA which is responsible for controlling and directing all the activities of cell.
Cord? Or maybe vein. But I strongly believe it’s cord
25% is the probability of a homozygous recessive offspring if both parents are heterozygous.
Answer:
The Correct Option of the Given Scenario is "Binds Divalent Metal Cations That Constrain the PCR Reaction"
Explanation:
The part that Chelex show in the segregation of genomic DNA is normally that the Chelex Formulate the PCR. The sightless Restraints like 
Get involved to the DNA there by mortifying and make it unbalanced for PCR
