Disease
Science

A disease that is spread by pathogens, from an infected organism or the environment
Infectious disease
A disease that is spread by pathogens, from an infected organism or the environment. Infectious disease. It is an illness caused by microbes like bacteria, viruses, or fungi that can spread to others.

Physical or mental discomfort, like panic before a test or a pain from carrying heavy books
Mental stress
Physical or mental discomfort, like panic before a test or a pain from carrying heavy books. Mental stress. Mental stress is the brain's response to challenging situations, activating the body's fight-or-flight mechanisms.

A disease that is not spread from one person to another, like asthma and diabetes
Noninfectious disease
A disease that is not spread from one person to another, like asthma and diabetes, is called a noninfectious disease. Noninfectious diseases are medical conditions that are not caused by infectious agents and cannot be passed from person to person.

A lymphocyte that identifies pathogens and attacks infected cells, it matures in the thymus
T cell
A lymphocyte that identifies pathogens and attacks infected cells, it matures in the thymus. T cell. T cells are immune cells that help protect the body by identifying and destroying infected or cancerous cells.

A substance made of weakened or dead pathogens, it gives the body immunity against disease
Vaccine
A substance made of weakened or dead pathogens, it gives the body immunity against disease. Vaccine. A vaccine teaches the immune system to recognize and fight specific diseases without causing the illness.