Health: The Lymphatic System and Immunity
How the body moves lymph and fights germs
Health: The Lymphatic System and Immunity
How the body moves lymph and fights germs
Health - Grade 6-8
- 1
What is the main job of the lymphatic system?
Think about fluid balance and defense against disease.
The main job of the lymphatic system is to collect extra fluid from body tissues, return it to the bloodstream, and help the immune system fight germs. - 2
Lymph is a clear fluid that travels through lymph vessels. Name two things lymph may carry.
Lymph may carry extra fluid from tissues, white blood cells, fats from digestion, and waste materials. Any two of these are correct. - 3
Explain why lymph nodes often swell when a person has an infection.
Lymph nodes act like small filters and immune cell meeting places.
Lymph nodes can swell during an infection because they are filtering germs and making more immune cells to help fight the infection. - 4
Match each lymphatic structure to its function: lymph vessels, lymph nodes, spleen, thymus. Functions: filters lymph, carries lymph, helps T cells mature, filters blood.
Lymph vessels carry lymph. Lymph nodes filter lymph. The spleen filters blood. The thymus helps T cells mature. - 5
What are white blood cells, and why are they important for immunity?
White blood cells are part of the body's defense team.
White blood cells are immune system cells that help protect the body from germs, harmful substances, and abnormal cells. They are important because they help find, attack, and remember invaders. - 6
Describe the difference between a pathogen and an antigen.
A pathogen is a germ or other organism that can cause disease. An antigen is a marker or substance that the immune system recognizes as foreign or harmful. - 7
A virus enters the body through the nose. Put these events in a logical order: immune cells respond, virus enters the body, symptoms may appear, body recognizes the virus as foreign.
Start with exposure, then recognition, then response.
The logical order is: virus enters the body, body recognizes the virus as foreign, immune cells respond, and symptoms may appear. - 8
What is the purpose of antibodies?
Antibodies are proteins made by the immune system that attach to specific antigens. They help mark germs for destruction or block germs from infecting cells. - 9
Explain how vaccines help the immune system prepare for future infections.
Vaccines work by training immune memory.
Vaccines help the immune system learn to recognize a specific pathogen or antigen without causing the full disease. This helps the body respond faster if it meets the real germ later. - 10
List three healthy habits that can support the immune system.
Three healthy habits that can support the immune system are getting enough sleep, eating nutritious foods, staying physically active, washing hands, managing stress, and staying up to date on recommended vaccines. Any three reasonable habits are correct. - 11
Why is handwashing an important way to reduce infections?
Think about how germs often travel from surfaces to the body.
Handwashing is important because it removes many germs from the hands before they can enter the body through the mouth, nose, eyes, or breaks in the skin. - 12
A student says, "The lymphatic system only works when you are sick." Explain why this statement is not correct.
This statement is not correct because the lymphatic system works all the time. It constantly returns extra fluid to the blood, transports some fats, filters lymph, and helps monitor the body for germs.