Natural Body Defenses

Question 1

What is the first stage of defense?

Answer 1

Skin
Eyes- blinking, tears keep dirt out 
Mucus & Cilia
- mucus traps material 
- small hairs keep material away 
Stomach Acid 
- Acid kills most microbes

Question 2

What is the second stage of defense?

Answer 2

Blood - bleeding washes
Platelets - clot blood
Fibrinogen - protein forms across cut
Macrophages- white blood cells- destroy bacteria
White blood cells
- can engulf microbes (consume and destroy them)
- can produce antibodies (fight infection)
- can neutralize poisons or toxins

Question 3

What is the third stage of defense?

Answer 3

Antibodies: Are special proteins made by white blood cells
Antigens: invading microorganism or the toxins they produce
Antibodies destroy antigens
An antibody for one antigen doesn’t affect all antigens.
Lymphocytes- White Blood Cells
- Make antibodies
- Found in blood, lymph, tonsils, liver and spleen
Made in bone marrow

Question 4

What are the two types of diseases?

Answer 4

Non-infectious, infectious

Question 5

What are non-infectious diseases?

Answer 5

From lifestyle choices- heart disease, cancer
Immune Malfunction- allergies, eczema, arthritis
Parasites- worms, lice, ticks, fleas
Genetics- hemophilia, down syndrome
Incorrect body function- diabetes, tumors

Question 6

What are the four types of infectious pathogens?

Answer 6

Protozoa, Fungi, Bacteria, Viruses

Question 7

How do phagocyte defend against pathogens?

Answer 7

Phagocyte surround any pathogens in the blood and engulf them. They are attracted to pathogens and bind to them.

Question 8

How can someone avoid diseases?

Answer 8

They can wash their hands with warm water and soap often, get immunizations and vaccines and make good lifestyle choices.