Organic matter in soil is also called humus.
compound consisting of a nucleoside linked to a phosphate group. Nucleotides form the basic structural unit of nucleic acids such as DNA.
The respiratory system brings air into the lungs supplying the blood with oxygen. Oxygen is carried throughout the body to the organs and keeps the heart pumping and when the blood circulates back to the lungs the process starts over again.
B. Net movement in osmosis is from areas of higher concentration to areas of lower concentration. Net movement in diffusion occurs from areas of higher concentration to areas of lower concentration.
Radiation: is the emission or transmission of energy in the form of waves or particles through space or through a material medium.
Examples: Radio waves, microwaves, infrared, visible light, ultraviolet, x-rays, and gamma radiation