Answer:
D
Explanation:
Fossils tell us where they came from.
Have a great day
Explanation:
The main building material in the body.
They are carriers of vitamins, hormones, fatty acids and other substances.
Provide the normal functioning of the immune system.
Provide the state of the "apparatus of heredity".
They are catalysts of all biochemical metabolic reactions of the body.
As of 2014, it was often reported in popular media and in the scientific literature that there are about 10<span> times as many microbial cells in the human body than there are human cells; this figure was based on estimates that the human microbiome includes around </span>100 trillion<span> bacterial cells and an adult human</span>
Melting of ice and island decreasing in level
Simple diffusion is the process by which a substance moves across a cell membrane from an area of high concentration to an area of low concentration. Substances that move by simple diffusion are able to diffuse directly across the phospholipid bilayer of the cell membrane. These substances are generally small and neutral, as large or charged particles cannot cross the phospholipid bilayer. Some examples of molecules that move by simple diffusion are carbon dioxide and oxygen.
Facilitated diffusion is the process by which a substance moves across a cell membrane from an area of high concentration to an area of low concentration with the aid of a membrane protein. Substances that move by facilitated diffusion are not able to diffuse directly across the phospholipid bilayer of the cell membrane. These substances are generally large and/or charged. They therefore travel through a protein channel in the cell membrane along their concentration gradient. Some examples of substances that can move by facilitated diffusion are glucose, sodium ions and chloride ions.
The similarities between facilitated diffusion and simple diffusion are:
They both involve the movement of a substance across a cell membrane along its concentration gradient (from an area of high concentration to an area of low concentration).
They are both examples of passive transport, as neither requires energy from the cell to move the substance across the membrane.
