They inhibit lh and fsh hormone this stop the maturation of follicles henve they are not released and sperm has nothing to fuse so fertilisation doesn't occur
A mutation which occurs when a base is introduced into the DNA sequence before transcription begins will lead to frame-shift of a single base on the DNA sequence resulting in nonfunctional protein from the transcribed mRNA.
Explanation:
This change either through addition or deletion of a single base in the codon sequences of the DNA will modify the amino acid codes and will result in nonfunctional proteins after transcription.
This mutation will just result in change of a single base, i.e., it would be added either to the enhancer region or the silencer region of the sequence before the promoter which initiates transcription.
The mRNA produced due to mutated DNA sequence after the deletion or insertion point will be read as out of frame thus resulting in nonsense protein.
<span>Human skin color is a polygenic trait, which means that multiple gene loci (with different alleles) are involved in its expression. It has been shown that there more than 350 genetic loci involved in determining skin color. Because of that, there is the enormous number of possible genotypes for the skin color and as a result, the phenotypes vary from the darkest brown to the lightest hues.</span> <span> Different populations have different allele frequencies of genes for human skin color, and the combination of these allele variations brings about complex and continuous variation in skin coloration. Natural skin color can change due to exposure to sunlight (becomes darker) and that is the way it adapts to intense sunlight irradiation (protection against the UV exposure).</span>
Answer:
Explanation:
1 Long term exposure to harmful genotoxic chemicals or ionizing radiation can cause changes in the base sequence of DNA.Chemicals might induce DNA mutations, such as polycyclic hydrocarbons (fumes found in oil stations, or smoke from a tobacco cigarette), intercalating agents such as Ethidium Bromide (carcinogen), but also radiations such as UV-radiation (C and T bases are most vulnerable and would bind to identical bases unstead of their
2 Genetic changes that are described as de novo (new) mutations can be either hereditary or somatic. In some cases, the mutation occurs in a person’s egg or sperm cell but is not present in any of the person’s other cells. In other cases, the mutation occurs in the fertilized egg shortly after the egg and sperm cells unite. (It is often impossible to tell exactly when a de novo mutation happened.) As the fertilized egg divides, each resulting cell in the growing embryo will have the mutation. De novo mutations may explain genetic disorders in which an affected child has a mutation in every cell in the body but the parents do not, and there is no family history of the disorder.
Somatic mutations that happen in a single cell early in embryonic development can lead to a situation called mosaicism. These genetic changes are not present in a parent’s egg or sperm cells, or in the fertilized egg, but happen a bit later when the embryo includes several cells. As all the cells divide during growth and development, cells that arise from the cell with the altered gene will have the mutation, while other cells will not. Depending on the mutation and how many cells are affected, mosaicism may or may not cause health problems.
Answer - cohesion- attraction of molecules for another molecule of the same kind.
