Answer:
Hemophilia is a sex-linked recessive disorder in which a person's blood do not clots and he can bleed to death even after minor injuries because blood will keep running due to a small cut.
It is a recessive trait which means that even if one normal gene is present along with Hemophiliac gene, the person will not have the disease and he will be the carrier.
Question: What will be their children’s possible phenotypes?
If a woman who is a carrier for hemophilia marries a hemophiliac man, their genotypes can be denotes as :
Here H, indicate normal gene and small h indicate defected (hemophilia) gene.
Parents: XHXh X XhY
Offspring: XHXh : XHY: XhXh: XhY
Phenotype of offspring:
XHXh: The child will be daughter and normal (25 % chances)
XHY: The child will be son and normal (25 % chances)
XhXh: The child will be girl and Hemophiliac (25 % chances)
XhY: The child will be son and Hemophiliac (25 % chances)
Hope it helps!
B. Increased exposure to UV light increases the risk of mutation occurring.
Answer:
The answer is A
By the late 1830s, botanist Matthias Schleiden and zoologist Theodor Schwann were studying tissues and proposed the unified cell theory. The unified cell theory states that: all living things are composed of one or more cells; the cell is the basic unit of life; and new cells arise from existing cells.
The longest phase of mitosis is prophase. Because the nuclear membrane disappears, Nucleolus disintegrates, and the DNA condensed to form chromosomes (each chromosome is composed of sister chromatids attached around centromere.)
Answer: primary succession.
Explanation: