________ is a group of cells that have similar structure and that function together as a unit.

________ are very small, single-celled organisms that are found almost everywhere.

________ is a condition of the living animal or plant body or of one of its parts that impairs normal functioning and is typically manifested by distinguishing signs and symptoms.

Toxins are poisonous substances that are a specific product of the metabolic activities of a living organism and are usually very unstable, notably toxic when introduced into the tissues, and typically capable of inducing antibody formation.

________ is the soft, spongy tissue that has many blood vessels and is found in the center of most bones.

True or False: Bloodstream is the flowing blood in the respiratory system.

________ - any substance that causes the body to make an immune response against that substance.

The two main types of lymphocytes are _____ & _____.

_______ - a protein made by plasma cells (a type of white blood cell) in response to an antigen.

________ - a condition in which the body's immune system mistakes its own healthy tissues as foreign and attacks them.

A ________ is a virus, a microorganism, or another agent that cause a disease.

Select all that are Infectious Diseases.

Select all that are Noninfectious Diseases.

Your body's first line of defense against disease begins with: