Answer: Skin cancer
Explanation:
Melanin is a pigment derived from an amino called acid tyrosine. The most common form of melanin is called eumelanin, which is a polymer of dihydroxyindole carboxylic acids and their reduced forms.<u> When a person is exposed to the ultraviolet light (UV) from the sun, the melanocytes will produce eumelanin to prevent the skin from burning and damage to the cell nuclei (where DNA is found)</u> of the epidermis. This melanin production causes the skin to darken. The eumelanin in the skin then acts as a natural sunscreen by blocking the damaging effects of sunlight. So, skin darkens when exposed UV light, thus providing greater protection when needed by producing more eumelanin, but it also becomes more likely to develop melanoma, which is a type of skin cancer. This is because UV rays damage the DNA of skin cells. <u>The DNA (deoxyribonucleic acid) is the genetic material that has the instructios to the growth and functioning</u> of an organisms). Skin cancers begin when eumelanin protection is not sufficient and this damage affects the DNA of the genes that control the growth of skin cells. <u>This results in a tumor, which is the uncontrolled growth of cells </u>(in this case, skin cells) because there will be a mutation in DNA that affects the function of the cells.
Answer: Option D
During isovolumetric contraction blood is flowing from the ventricles into the aorta and pulmonary arteries.
Explanation:
Isovolumetric contraction is an occurrence that happen in the systole where the ventricle contracts with no change in volume. Isovolumetric contraction causes the left ventricles pressure to rise above the atrial pressure which shut the mital valve and cause the first heart sound. When the pressure rises in the left ventricle, it contracts and pump blood to the aorta and pulmonary arteries. The ventricles continue to contract and blood continue to flow to the aorta and pulmonary arteries in the systole.
Estrogen is a<span>ny group of steroid hormones that promote the development and maintenance of female characteristics of the body.</span>