Answer:
Mutations of enzymes involved in nucleotide excision repair.
Explanation:
- Xeroderma pigmentosum is a genetic disorder and the person suffering from this disorder is sensitive to ultraviolet light due to the disability of the enzymes involved in nucleotide excision repair which prevents DNA damage caused by ultraviolet light.
- Thus, the individuals are sensitive to the exposure of UV and suffer severe problems when exposed to sunlight.
- The major cause of the disorder is the inability to repair DNA damage caused by exposure to sunlight due to the mutation in an enzyme involved in nucleotide excision repair.
- Nucleotide excision repair is a DNA repair process that can excise out single-stranded DNA that is damaged by UV.
- UV exposure leads to the addition of bulky adducts in the DNA known as thymine dimers. The enzymes of NER are involved in the removal of these adducts by excising out a segment of DNA that contains such lesions.
- However, in the case of XP, the mutations make this repair system non-functional or partially functional and thus, the individual becomes highly sensitive to UV exposure.
Answer: pretty sure its haploid cells
Explanation:
Answer:
1. genetics
2. constant
3. genetic drift
4. Modern synthesis combines the ideas surrounding evolution and natural selection with those of genetics.
5. A genotype is the genetic makeup of an organism. It describes the DNA that underlies a trait. There are dominant and recessive alleles and heterozygous and homozygous genotypes. A phenotype is the physical manifestation of that genotype.
6. The most common type of mutation is a deleterious mutation. Natural selection acts to remove this allele from the population.
7. The most common type of observed mutation is a neutral mutation. This mutation doesn't impact natural selection in any noticeable way since it doesn't impact the fit of that organism. Since neutral mutations convey no advantage, they generally must spread in a population through drift. Many also will disappear through drift.
8. During sexual reproduction, each organism is provided a copy of chromosomes from each parent, and this allows for new combinations of DNA.
9. This isn't an example of genetic drift because there's a genetic component to the ability to withstand severe temperatures. Therefore, this is an example of natural selection, related to surviving extreme environmental conditions
Explanation:
1. i
2.a
3.d
4.b
5.e
6.c
7.g
8.f