D.
They have the same number of protons as electrons.
Explanation:
Protons are found in the nucleus of the atom and have a positive charge while electrons orbit around the nucleus and have a negative charge. Usually, in a neutral atom of an element, the number of protons is equal to the number of electrons. This is why the atom has no charge because the positive and negative charges cancel out. When an atom loses an electron its charge turns positive while when it gains an electron its charge turns negative.
<span>Warmer summertime temperatures in the northern hemisphere are due partly to the tilt of the earth's axis around the sun when it is at its lowest point. The northern hemisphere has usually shorter hours in the day and longer hours in the night that is why it always happen during the winter. Because the sun is a bit far away from these islands, people living in this area will expect colder atmosphere.
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Answer: If a cell is placed in a hypertonic solution, water will leave the cell, and the cell will shrink. In an isotonic environment, there is no net water movement, so there is no change in the size of the cell. When a cell is placed in a hypotonic environment, water will enter the cell, and the cell will swell.
Explanation:
<span>The answer is A. This is because the P53 gene is involved in a cell cycle regulation and is thought to hold the cell in a particular phase until DNA defects are repaired. </span>