Because natural selection can only increase or decrease frequency of alleles that already exist in the population
<span>If a treatment suddenly lowers your serotonin level you may feel sluggish and should consult a doctor immediately. There are prescription drugs which can stabilize serotonin levels, but must be prescribed by a doctor.</span>
Answer:
Gravity is considered to be one of the universal forces inherent of nature itself. Gravity is an attractive force between objects, which is proportional to the mass of the objects and inversely proportional to the distance between them. Gravity is what help planets follow an elliptical orbit, and is the reason why we can keep our feet on the surface of the earth.
The answer is chloroplasts and mitochondria.
<span>When solar energy in the form of sunlight reaches a leaf of a plant, it passes through the leaf to chloroplasts. Chloroplasts contain pigment chlorophyll which is excited by light. As the result, </span>a series of chemical reactions occur in the chloroplasts and carbon dioxide and water are converted into glucose and oxygen. Now, glucose is broken down and transported into mitochondria where through different processes (Krebs cycle and electron transport chain) energy is produced in the form of ATP.<span>
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Answer: The answer is 4
Explanation:
Vitamin D controls your skin pigment. It's kind of like when someone has an iron deficiency they get bruises and they turn a whiter shade.
Hope I helped :)