C. All cells arise form previously existing cells. This is because the scraped knee's cells would be replaced by the exact same ones that were removed. Kind of like "Out with the old and in with the new... yet the exact same..!"
Hope this helps!
Answer:si
Explanation:hope I helped
Question in English:
A female carries a recessive lethal gene (l) on one of her X chromosomes, and a normal dominant allele (L) on the other. What is the sex ratio to be expected in this woman's dependency if she marries a normal man?
Answer:
2/3 females
1/3 males
Explanation:
Females have two X chromosomes (XX) and males have an X and a Y chromosome (XY).
The genotype of the female is XLXl. The genotype of the male is XLY, since he is normal.
The possible genotypes are:
<u> XL Xl</u>
<u>XL</u> <em>XLXL XLXl</em>
<u>Y</u> <em>XLY </em><em>XlY</em>
<em />
All female offspring will be normal as they will always have one normal copy of the X chromosome from their father.
50% of the male offspring will be normal, but 50% will inherit the lethal gene from their mother.
Because the allele is lethal, that means XlY males will not be born.
That means 2/3 of the children will be females, and 1/3 will be males.
There are two types of cell division: mitosis and meiosis. Most of the time when people refer to “cell division,” they mean mitosis, the process of making new body cells. Meiosis is the type of cell division that creates egg and sperm cells. Mitosis is a fundamental process for life.
