Answer:
given, mother and father are heterozygotes.
let, father has B blood group and mother has A blood group.
then their heterozygous genotypes are --
father = iB, iO and mother = iA, iO
punnett square will be,
iB iO
iA iA iB iA iO
iO iB iO iO iO
the genotypes of their progeny will be, iAiB , iAiO ,iBiO and iOiO
and phenotypes will be 3 are heterozygous and 1 is homozygous.
Nondisjunction is the failure of one or more pairs of homologous chromosomes or sister chromatic.
Answer:
with dipping a paper towel strand into water.
Explanation:
this mimics the xylem.
in the nucleolus ribosomes are made.