The <span>Mid-Atlantic Ridge</span>
Answer:
primary, secondary
Explanation:
primary immunodeficiency diseases are present at birth and usually stem from genetic errors, whereas secondary immunodeficiency diseases are acquired after birth and are due to agents such as infections, irradiation, or steroids
Answer;
Antibodies.
The human immune system fights infection by releasing antibodies.
Explanation;
The immune system acts to defend the body against pathogens such as viruses, bacteria and fungi that may cause a disease.
It does so using various types of mechanism, one is by the production of antibodies.
Antibodies are proteins that are produced by the B-cell and are used by the immune system to identify and neutralize pathogens.
These antibodies also activates proteins known as complements which assist in the killing of bacteria, viruses and the infected cells.
Explanation:
Extinction occurs when a species is not able to adapt to changing environmental conditions,not able to successfully reproduce and dies out.
Lichens are organisms made of two different species, algae and fungi, lifing together in a symbiotic relationship.
