Answer:
Explanation:
Wind t Water + Season changing
Answer:
the complex of nerve tissues that controls the activities of the body. In vertebrates it comprises the brain and spinal cord.
Explanation:
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Answer:
True
Explanation:
The color of the baby's eyes is influenced by the genetic inheritance (of the genes transmitted by the mother and father) and the amount of melanin (brown or black pigment whose type and amount is encoded in the genes) found in the iris.
Eye color is controlled by at least three genes, although researchers still only understand the role of two of them. Determining eye color is an extremely complex process and there are several conditioning factors and genetic combinations that can influence the final color.
The more melanin, the darker the color of eyes, skin and hair. If parents have both brown eyes, it is natural for their children to have the same color. However, there may be a genetic influence from an ancestor and the child expressing a different color.
If the presence of melanin in the iris is reduced, the baby will have blue eyes, even if father and mother have brown eyes. If the presence of melanin is higher, the eye color will be green or hazel. When there is a large production of melanin, the eyes are brown, predominant color over green or blue and therefore more common. The least common color is green.
A relatively small blood pressure gradient is generally insufficient to move blood through the veins under given conditions, thus venous return must be facilitated by valves within veins and two "pumps." ... As skeletal muscles contract, veins are squeezed to help propel the blood toward the heart.