Lastly, write the letter for each allele across each column or down each row. The resultant mix is the genotype for the offspring. In this case, each offspring has a Tt (heterozygous tall) genotype, and simply a "Tall" phenotype.
Here we have some more interesting results: First we now have 3 genotypes (TT, Tt, & tt) in a 1:2:1 genotypic ratio . We now have 2 different phenotypes (Tall & short) in a 3:1 Phenotypic ratio . This is the common outcome from such crosses.
Take the offspring and cross them since they are donating alleles for 2 traits, each parent in the f1 generation can give 4 possible combination of alleles. TW, Tw, tW, or tw. The cross should look like this. (The mathematical “foil” method can often be used here)
A person can receive blood only when the donor's blood type does not contain any surface antigen the recipient does not. This is because the recipient has antibodies which will attack any foreign surface protein.
Thus, Type AB can accept any blood types because it will not attack A or B surface antigens. However, a type AB person could only donate blood to another AB person. They are known as Universal Recipients .
Also, Type O persons are Universal donors because they have NO surface antigens that recipients' immune systems can attack. Type O persons can ONLY receive blood from other type O persons.
There is another blood type factor known as Rh.
People are either Rh+ or Rh- based on a basic dominant/recessive mechanism.
Not usually a problem except with pregnancy.
It is possible that an Rh- mother can carry an Rh+ fetus and develop antibodies which will attack & destroy the fetal blood
This usually occurs with 2nd or 3rd pregnancies, and is detectable and treatable.