1. an atom
2. compound
3. both
4. atom
Answer: A geneticist studies a series of families in which both parents are normal and at least one child has albinism. The geneticist reasons that both parents in these families must be heterozygotes and that albinism should appear in of the children of these families. To his surprise, the geneticist finds that the frequency of albinism among me children of these families is considerably greater "Than . Can you think of an explanation for the Thigher-than-expected frequency of albinism among These families?
Explanation:
Answer:
I think you're referring to the Metaphase...
Explanation:
During Cell Division (or, rather before!) the DNA needs to be replicated. This normally is done by DNA Polymerase, and results in two identical double strands (the "Sister Chromatids".
These chromatids are held together at the Centromere, which will be the heart of the "X"-shape. After that the DNA is packed into Chromosomes by winding it around proteins called Histones. If I remember correctly there are 5 different Histones.
This "Zipping Up" makes the chromosomes more visible.
As the two sister chromatids are still connected, the result is the X-shaped Metaphase Chromosome....
D. Lymph nodes are the filtering points throughout the body... found in the lymphatic system
