Science Ch.18

Why do blood vessels widen when a pathogen has invaded the body's cells?

Blood vessels widen when a pathogen has invaded the body's cells, to allow for more blood flow to the affected area which increases the number of white blood cells, attacking the pathogen.

Antigens

molecules that the immune system recognizes either as part of your body or as coming from outside your body

Immunity

the body's ability to destroy pathogens before they can cause disease

Vaccination

the process by which harmless antigens are deliberately introduced into a person's body to produce active immunity.

HIV

the virus that causes AIDS

In what 4 ways can HIV be spread?

HIV can be spread by reproductive fluids, breast milk, blood exchange, and previously used needles.

How is HIV different than any other virus?

HIV is different than other any virus, because it can survive for a short time outside the human body in body fluids.

Inflammatory Response

The body's second line of defense. In this response fluid and white blood cells leak from blood vessels into nearby tissue. The white blood cells then fight the pathogens.

Name the 4 kinds of pathogens. Give an example of each.

The four kinds of pathogens are bacteria, viruses, fungi, and protists. An example of bacteria is Tetanus. An example of viruses is the cold or flu. An example of fungi is athlete's foot. An example of protists is Malaria.

In what 4 ways are pathogens spread?

The four ways in which pathogens are spread are infected people; soil, food, and water; contaminated objects; and infected animals

Allergy

a disorder in which the immune system is overly sensitive to a foreign substance

Asthma

a disorder in which the respiratory passages narrow significantly

T cells

a lymphocyte that identifies one pathogen from another

B cells

a lymphocyte that produces proteins that help destroy pathogens

Toxin

a poison produced by bacterial pathogens that damage cells

Antibodies

a protein produced by a B Cell of the immune system that destroys pathogens

Carcinogens

a substance or a factor in the environment that can cause cancer

Phagocyte

a white blood cell that engulfs pathogens and destroys them by breaking them down

Tumors

an abnormal tissue mass that results from the rapid division of cells

Allergen

any substance that causes an allergy

Lymphocytes

white blood cells that distinguish between different kinds of pathogens

Insulin

chemical that enables the body cells to take in glucose from the blood and use it as energy

Diabetes

condition in which the pancreas fails to produce enough insulin or the body's cells fail to properly use insulin

Noninfectious Diseases

diseases that are not caused by pathogens in the body

Passive Immunity

immunity in which antibodies are given to a person rather than produced within the person's own body

Describe the body's first line of defense against pathogens.

-the body's first line of defense against pathogens are barriers that trap and kill most pathogens with which you come into contact. The surfaces of the skin, breathing passages, mouth, and stomach function as these barriers. In the skin destructive chemicals in oil and sweat kill the pathogens; if the chemicals don't kill the pathogens then the pathogens will fall off with dead skin cells. The breathing passages trap the pathogens with mucus, and the pathogens are forced out of the body, by sneezing or coughing. In your mouth pathogens are destroyed by destructive chemicals in saliva. In the stomach acid destroys the pathogens.

AIDS

A disease caused by a virus that attacks the immune system

Is a fever a good or bad thing? Explain.

A fever is a good thing. It makes you feel bad, however, it actually helps your body fight off infection. This is because some pathogens don't grow and reproduce in high temperatures.

What triggers the immune response?

If a pathogen is severe enough to cause a fever, it triggers the immune response

Active Immunity

Immunity that occurs when a person's own immune system produces antibodies in response to the presence of a pathogen

Pathogens

Organisms that cause disease

Immunity response

Part of the body's defense against pathogens, in which cells of the immune system react to each kind of pathogen with a defense targeted specifically at the pathogen

How does the skin protect against pathogens?

The skin protects against pathogens, with destructive chemicals and dead skin cells. The destructive chemicals in oil and sweat destroy the pathogens. If the pathogens are not destroyed by these chemicals, they will fall off with dead skin cells

Vaccine

The substance that is used in a vaccination. It usually consists of pathogens that have been weakened or killed but can still trigger the immune system to go into action

What 2 men discovered pathogens and their affects?

The two men who discovered pathogens and their affects are Robert Koch and Louis Pasteur.

Histamine

a chemical that is responsible for the symptoms od an allergy

Antibiotic

a chemical that kills bacteria or slows their growth without harming body cells

Infectious disease

a disease that is caused by the presence of a living thing within the body