Answer:
The correct answer is: A. active transport requires energy.
Explanation:
- Active transport can be defined as the physiological process by which molecules are enforced to migrate from a region where their concentration is low to a region where their concentration is high across a semi-permeable membrane. This occurs by the expenditure of energy. This type of movement is usually carried out by the integral membrane transport proteins or carrier proteins those remain interspersed across the plasma membrane.
- Passive transport can be defined as the physiological process in which no energy expenditure is required. This is because in this form of transport, molecules move from a region where their concentration is high to a region where their concentration is low, that is, down the gradient of their concentration, across a semi-permeable membrane. This type of movement can be mediated by simple diffusion or with the help of membrane transport proteins.
Answer:
14 Hydrogen is a very reactive gas, and the alkali metals are even more reactive. In fact, they are the most reactive metals and, along with the elements in group 17, are the most reactive of all elements.
15 The halogen group of elements is the most reactive of the nonmetals. It is also the most reactive group of all chemical elements. Fluorine is the most reactive element in this group. Halogens are highly reactive because they are all electronegative.
16 Group 8A — The Noble or Inert Gases. Group 8A (or VIIIA) of the periodic table are the noble gases or inert gases: helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn). The name comes from the fact that these elements are virtually unreactive towards other elements or compounds.
17 Group 1: Alkali Metals
Group 1 elements are called alkali metals because of their ability to displace H2(g) from water and create a basic solution. Alkali metals are also known to react violently and explosively with water.
The sun is the original source for ALL food webs