Only 200 out of 2 000, 000 sperm cells reach the ovum. And only one (in exception to very rare cases of two) sperm cells actually participate in the process of fertilization. In comparison, an average female only produces 400 of egg cells during their lifetime, but the eggs cells are significantly larger than sperm cells.
- Biology Definition: Respiration is a chemical reaction that happens in all living cells. (Both plant cells and animal cells). Respiration is the way that energy is released from glucose so that all the other chemical processes needed for life can happen.
- Normal definition: The action of breathing, also called ventilation.
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The correct answer is dynamo theory. The theory that explains the source of Earth's magnetic field is the dynamo theory. This theory proposes the mechanism of a celestial body such as Earth to generate magnetic field.
Answer: The Answer is D.
Explanation: Butter consists of butterfat, milk proteins and water, and often added salt. Most frequently made from cow's milk, butter can also be manufactured from the milk of other mammals, including sheep, goats, buffalo, and yaks.