Immuneand

IntegumentarySystems

Immune System

Functions•The immune system defends

against disease.

•It recognizes, attacks, and destroys foreign invaders such as bacteria and viruses.

Organs• Tonsils – lymph nodes in the throat• Thymus – T-Cells made in the bone are

matured here.• Lymph Nodes – small bean-shaped

masses• Spleen – filters blood for foreign particles

carried by the white blood cells.• Bone Marrow – makes white blood cells.

Immune System

Bone marrow

Tonsils

Thymus

Lymph node

Spleen

Lymphatic vessel

Tissues• White Blood Cells – blood cells whose main

function is to defend the body against disease.

• Lymphocytes – white blood cells.o T-Cells – lymphocytes made in the bone marrow and

mature in the Thymus gland whose function is to attack cells that have been invaded by viruses.

o B-Cells – lymphocytes made in the bone marrow that make antibodies to attack viruses in the blood.

How It Works

1. Recognition – White Blood Cells identify the antigens that do not belong in the body. (viruses & bacteria)

2. Activation – White Blood Cells attach to the foreign cells or viruses and destroy them.

3. Disposal – foreign cells and viruses are filtered out of the blood in the spleen.

Integumentary System(Skin)

Functions• Regulates body temperature• Keeps germs out of the body• Senses temperature, texture, pressure, and pain.• Releases oil, waste and salt in sweat.• Shields body from UV rays• Produces vitamin D from UV rays.• Provides waterproof covering that prevents

dehydration.

Specialized Cells• Epidermis – outer layer of skin mostly

made up of dead cells.

• Dermis – functional layer of skin below the epidermis.

How It Works

Epidermis• Keratin – strong flexible protein that make

skin tough and waterproof.

• Melanin – pigment that gives skin its color and shields the body from UV

rays.

Dermis• Contains – blood vessels, nerves, sweat

glands, oil glands, and hair follicles.

• Collagen – protein fibers that make skin flexible.