DNA is considered the molecule of life because it contains the instructions that ensure the continuity of life. Employment of DNA to code for protein is the basis of all life on earth.
In all living things, inherited DNA is used to code for amino acids which when joined or linked together in a deliberate specific manner form polypeptides which make up proteins. These proteins are responsible for structure and function of cells.
For example DNA provides information to make four polypeptide (two beta and two alpha ) chains which make up hemoglobin, the protein that functions as the oxygen carrier in red blood cells. In summary,
DNA → protein → trait, and that relationship is the physical basis of life.
Genetics, blood type gene has two alleles, each allele has genotype A, B or O. The A and B are dominant, and O is recessive. So allele A combined with allele O is type A. Similarly, BO is type B, AA is type A, BB is type B, OO is type O, and AB is typeAB.
If both parents have type A blood, then the alleles could be AA or AO, thus the allele A frequency is 75%, allele O frequency is 25% for both parents.
So the chance of alleles OO is 25% × 25% = 6.25%,
alleles AA is 75% × 75% = 56.25%,
alleles AO is 75% × 25% = 18.75%,
alleles OA is 25% × 75% = 18.75%.
Since AA, AO and OA are blood type A, and OO is blood type O, thus their child has 6.25% chance to be blood type O and 93.75% chance to be blood type A.
The +/- is called the rhesus factor, with + being dominant, and - being recessive.
So if both parents are -, the kids are always -, otherwise the kids might be + or -.
Child Blood Type Estimate Table:
Father's Blood TypeABABOMother's
Blood
TypeAA/OA/B/AB/OA/B/ABA/OBA/B/AB/OB/OA/B/ABB/OABA/B/ABA/B/ABA/B/
I think either neutral ph or more enzyme
