Where is the immune system

Primary lymphoid organs: These organs include the bone marrow and the thymus. They create special immune system cells called lymphocytes. Secondary lymphoid organs: These organs include the lymph nodes, the spleen, the tonsils and certain tissue in various mucous membrane layers in the body

Explanation: BRAINLIEST pls

humans can cause extinction of a species through overharvesting, pollution, habitat destruction, introduction of invasive species (such as new predators and food competitors), overhunting, and other influences. explosive, unsustainable human population growth is an essential cause of the extinction crisis.

explanation:

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