Antigens are proteins that are found on the surface of the pathogen and are viruses, fungi, or bacteria. Nonliving substances such as toxins, chemicals, drugs, and foreign particles. Antigens are usually carried by proteins and polysaccharides, and less frequently, lipids but it also needs to be attached to a large carrier molecule which is usually a protein. When an antigen enters the body, the immune system produces antibodies against it. The Antigen stimulates the immune system to produce antibodies. YOUR WELCOME ;)
<span>Cattle and sheep are exposed to lead and zinc when these poisons are in the grass/soil.
Cattle and sheep graze on the grass, and thus they intake these minerals, such as lead and zinc when they come in contact with grass or earth they may eat along with grass. Thus they are exposed to them via eating.
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Answer:
A source from which organisms generally take elements is called exchange pool (option B).
Explanation:
Options for this question are:
- <em>Food web.</em>
- <em>Exchange pool.</em>
- <em>Reservoir.</em>
- <em>Biotic community.</em>
The term exchange pool is related to the biogeochemical cycles that exist in nature, referring to the source from which elements present in the environment become part of living organisms.
<u>Exchange pools are the biotic components</u> -like animals and plants- of an ecosystem, which determine the passage of elements between living beings. An element can remain as a reservoir (abiotic) in the soil, and then be incorporated into the exchange pool.
