Plate tectonics is a scientific theory that describes the large-scale motion of Earth's lithosphere. Plates at our planet’s surface move because of the intense heat in the Earth’s core that causes molten rock in the mantle layer to move.
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Technically, there are an infinite number of possible amino acids, though we've found only 20 common ones that many organisms use and at least half a dozen obscure ones that specific organisms use. We focus only on the 20 common ones unless we're in a college level biochemistry course.
The three categories are nonpolar ones, polar ones, and charged ones. The nonpolar ones have non-polar side chains (no oxygens or nitrogens), the polar ones have polar side chains (most contain an OH group but no COOH group), the charged ones are either acidic or basic (has COOH group or a basic nitrogen).
Answer is: <span>solid wood.
There are </span>five fundamental states of matter (gas, liquid, solid, plasma and Bose–Einstein condensate).
<span>In solid, molecules are closely packed, stiff and do not changes of shape or volume. S</span><span>olid object (in this example wood) does not take on the shape of its container.
</span>Liquids (in this example water) <span>have definite volume, but no fixed shape.
</span>Gases (in this example nitrogen and neeon) not have definite volume and fixed shape, it depends on its container.
If two atoms** have the same number of protons, they are the same element. They have the same atomic number. The only thing that would change with the number of neutrons is the mass number.