cephalocaudal principle
The cephalocaudal principle states that development proceeds from top to bottom. According to this principle, a child will gain physical control of their head first. After this, physical control will move downward to the arms and lastly to the legs.
Answer:
50%
Explanation:
So the cross is hh x Hh
Making a punnet square would get Hh,hh,Hh,hh
The percent of babies that will have Hh is 50%
The earth orbits the sun once per year
Answer:
B. misalignment of the chromosomes during anaphase I
Explanation:
Aneuploidy refers to an error in the chromosomal number of a cell. This occurs when the chromosomes fail to separate equally into individual cells, a process called MEIOTIC NONDISJUNCTION. Meiotic disjunction can occur in either the anaphase stage of meiosis I or meiosis II, however, different outcomes are produced.
When chromosomes fail to separate at meiosis I, it results in two gametes that lack that particular chromosome (n-1) and two gametes with two copies of the chromosome (n+1). This means that the four daughter cells will have an incorrect number of chromosomes, hence, the misalignment of the chromosomes during anaphase I will result in four aneuploid daughter cells.