The Immune System: Your Body's Defense Team

What is the immune system?

• The immune system is a complex network of organs, tissues, cells, and molecules that work together to protect your body from harmful microbes called pathogens.

• The immune system is a digestive process that breaks down food into nutrients.

• The immune system is a system that controls movement and balance in the body.

• The immune system is a network responsible for producing energy in cells.

Which of the following is NOT a function of immune cells?

• A) Travel throughout your body

• B) Move through blood vessels and lymphatic vessels

• C) Act like tiny soldiers protecting your body from invaders

• D) Produce hormones

Bone marrow creates stem cells that develop into:

• Immune cells and red blood cells

• White blood cells and platelets

• Nerve cells and skin cells

• Muscle cells and fat cells

Where are lymph nodes located?

• Only in the chest

• Scattered throughout the body

• Only above the stomach

• Only in the bones

What is the main function of the spleen in the immune system?

• Produces hormones

• Filters blood and breaks down old red blood cells

• Stores fat

• Develops nerve cells

The thymus is located in the chest and is where special immune cells called ______ develop.

• T cells

• B cells

• Macrophages

• Neutrophils

Tonsils are lymphoid organs that help produce and store immune cells.

• True

• False

Match the lymphoid organ to its function:

• Creates stem cells

• Spleen

• Filters blood

• Bone Marrow

• Develops T cells

• Thymus

How do immune cells travel through the body? Choose the correct types of vessels:

• Blood vessels

• Lymphatic vessels

• Nerve vessels

• Digestive vessels

Fill in the blank: Immune cells move through ______ vessels and ______ vessels.

• blood; lymphatic

• arterial; venous

• digestive; respiratory

• nerve; muscle