Answer:
The correct answer is - option B. They are small because they lack a nucleus.
Explanation:
Red blood cells or erythrocytes are specialized cell that produce in bone marrow and have specific role such as carrying oxygen from lungs to deliver it to the various organs and carry out carbon dioxide.
In mammals these cells lack cell organelles such as nucleus and mitochondria, a major factor that determined its smaller size. The size of RBC are move through narrow vessels throughout a organism because of its specific size and shape that provide it space for hemoglobin and allow to be flexible and bend to move through narrow vessels.
Thus, the correct answer is : option B. They are small because they lack a nucleus.
The complete period of non division during the cell cycle is G0 (Gap zero).
In this case, the black body colour is the dominant one. The white dog is homozygous recessive.
As the cross between the black female 2 and the white male results in all black pups. This means that the all the offsprings are heterozygotes and the Female 1 is homozygous recessive having a BB phenotype (where B codes for dominant allele).
As the cross between the black female and the white male results in four white and three black pups. This means that the all the black offsprings are heterozygotes, and the white ones are homozygous recessive and the Female 2 have a dominant and 1 recessive gene, and is a hetrozygotezygous recessive having a Bb phenotype (where B codes for dominant allele and b codes for recessive allele).
D because having a sonogram is irrelevant when you are about to deliver the baby
Down syndrome can occur as the embryo has an extra chromosome. As well as this the embryo may die.
