Science of Disease Chapter 1

Virus

genetic material (RNA/DNA) and proteins; needs host cell to survive

Naked virus

don’t have an envelope and harder to kill

Enveloped virus

have an envelope

Antiviral or vaccines

used to treat viruses

Bacteria

single celled organisms, prokaryotic, some good, some bad

Good bacteria

help gut health

Bad bacteria

cause infection

Antibiotics or vaccines

used to treat Bacterial infections

Fungi

eukaryotic organisms, can be pathogens

Antifungal drugs

are used to treat fungal infections

Protozoa

eukaryotes, found in water or soil (ex

Parasites

organisms that use hosts to get nutrients at the expense of the host

Prions

nonliving proteins that cause abnormalities (ex. CJD)

One example of a viral infection

the flu

One example of a bacterial infection

Tuberculosis

One example of a fungal infection

Athlete’s foot

One example of a protozoal infection

Malaria

One example of a prion infection

CJD

One example of a parasitic infection

tapeworms

Immune system

the body’s tool for preventing or limiting infection

Bone marrow

produces B-cells and T-cells

Thymus

maturation of T-cells

Spleen

stores immune cells and filters your blood

Lymph nodes

immune cell activation sites

Lymphatic vessels

transport lymph throughout body that carries immune cells

Innate immune system

non-specific, quick response, no memory, present at birth

Adaptive immune system

highly specific, longer response, memory, needs exposure

Innate defenses

physical barriers, phagocytes, inflammation, natural killer cells

Physical barriers

skin, mucus

Phagocytes

cells that engulf pathogens

Natural killer cells

cells that target and destroy host cells

Macrophages

white blood cells that release cytokines

Cytokines

help white blood cells get to the infection

Mast cells

release histamine and blood cells to infection

Histamine causes the blood cells to become

leaky

Adaptive immune system

T-helper cells

Antigen presenting cells

show antigens on surface

T helper cells

match to correct antigen, bind to it, and destroy it.

B-Cells

produce antibodies to bind to and then neutralize the pathogen

Antibody structure

y-shape with antigen binding site on the end of the “y-stems”

Killer t-cells

recognize and destroy abnormal cells through apoptosis

Memory cells

some B and T cells become memory cells

Primary immune response

first exposure to pathogen, slower, will most likely get sick

Secondary immune response

second exposure to pathogen, faster, may not get sick

Active immunity

develops after exposure to pathogen

Passive immunity

gained by receiving antibodies (ex