Answer:
B. The father did not contribute a sex chromosome to his daughter due to nondisjunction of the sex chromosomes. The daughter is XO and her only X chromosome came from her mother, who was a carrier.
A.The mother's X chromosomes failed to separate during meiosis, and the daughter inherited two X chromosomes with the Lesch-Nyhan mutation. The father contributed no sex chromosomes.
Explanation:
As seen in the question above, a little girl was diagnosed with Lesch-Nyhan syndrome, which is an X-linked recessive condition caused by a mutation in the HPRT1 gene responsible for purine metabolism.
The little girl's parents do not have the syndrome, and no one in the little girl's paternal family presented this syndrome, however, we know that the maternal grandfather of the little girl's mother had the syndrome, which means that it was the mother's genetic material that contributed to the development of the syndrome in the little girl. This was because the little girl did not receive any X chromosomes from her father, but she inherited the two X chromosomes from her mother that coded for the Lesch-Nyhan mutation. This happened because the mother's X chromosome disjuction did not occur during meiosis I.
As shown above, the father did not contribute any sex chromosomes to his daughter, which means that the daughter is XO and her only X chromosome came from her mother, who was a carrier.
A serious, inflammatory condition
in which the colon mucosa protrudes through the colon wall is called diverticulitis.
Diverticulitis is a related digestive condition that affects the colon. This
condition occurs when naturally weak part of the colon tears which result in
inflammation or infection. Symptoms of diverticulitis include severe abdominal
pain, fever, nausea and constipation.
Answer:
mitosis
Explanation:
Gametes are produced by mitosis (not meiosis) and after fertilization a diploid zygote is created. The single zygote cell never grows or divides my mitosis. It can only divide by meiosis to produce haploid cells once more, which then produce the main adult body.
Answer:
Cause: Dropping the egg
Effect: The egg breaks
Explanation:
Assuming there is no comfort for the egg when it reaches the ground or surface you're dropping it on, the egg will break. The egg breaks because you dropped it 4 feet, making the effect be the broken egg.