Answer:
Two people with brown hair could have a child with blonde hair, but only if they are both heterozygous.
Answer:
A hair follicle anchors each hair into the skin.
Explanation:
The hair bulb forms the base of the hair follicle. In the hair bulb, living cells divide and grow to build the hair shaft. Blood vessels nourish the cells in the hair bulb, and deliver hormones that modify hair growth and structure at different times of life.
I think the correct answer from the choices listed above is option A. When crossing-over takes place, chromosomes exchange corresponding segments of DNA. Corresponding genes on non-sister chromatids are exchanged at chiasmata. Hope this answers the question.
Answer:
b. Replicated chromosomes line up on the equatorial plate.
Explanation:
Mitosis starts with the breakdown of the nuclear envelop and condensation of chromatids into visible chromosomes. Since DNA replication has occurred during the S-phase of interphase, each chromosome has two sister chromatids held together by a centromere. A chromosome with two sister chromatids is said to be a replicated chromosome.
Metaphase of mitosis includes the alignment of replicated chromosomes at the cell's equator. The process is assisted by the spindle apparatus. This is followed by splitting of centromere and separation of sister chromatids during anaphase.