Chemical reactions occur when chemical bonds between atoms are formed or broken. The substances that go into a chemical reaction are called the reactants, and the substances produced at the end of the reaction are known as the products.
Answer:
E. that area of the membrane is in the absolutely refractory period.
Explanation:
Refractory period is a period during which neuron cell cannot be stimulated (depolarized). This is why the action potential can only travel in one direction from the neuron body towards axon.
Refractory period occurs because of the inactivation of voltage-gated sodium channels (while action potential is at its peak) which cannot be open for a certain period of time. and membrane cannot be depolarized.
<span>Spiral galaxies are generally classified as galaxies that are circular in nature, with a bright nucleus that is enclosed by a thin outer disc. Normal spiral galaxies and barred spiral galaxies differ in appearance because normal spirals have 'arms' that emanate from the nucleus (which looks like a sphere that has curved arms coming out of the nucleus center), while barred spirals have bars (bright line features) that go straight through the nucleus, with arms that unwind from the ends of the bar.
Elliptical galaxies look like very bright stars - they are shaped like elongated spheres, emanate a lot of light (but the brightness is concentrated in the center and dissipates the further out from the center you go), and vary in size.
Irregular galaxies are classified as such because they don't fit into either the spiral or elliptical galaxy groups. They have a wide variety of shapes and sizes, and have no inherent regular or symmetrical structure.</span>
Plants remove carbon dioxide from the atmosphere, and release oxygen into the atmosphere. Humans and animals remove oxygen from the atmosphere, and release carbon dioxide into the atmosphere.