Microbiology Finals (Part 3 of 3)

is the scientific study of disease (pathos = suffering; logos = science)

study of causation; the cause of a disease

the manner in which a disease develops.

the invasion or colonization of the body by pathogenic microorganisms

is an abnormal state in which part or all of the body is not properly adjusted or incapable of performing its normal functions

is the ability of a pathogen to establish an infection

capacity of a microorganism to cause disease

The quality or state of being capable of causing disease

The relationship between the normal microbiota and the host

One organism benefits, and rhe other is unaffected

Both organism benefits

One organism benefits at the expense ofthe other

They ordinarily do not cause disease in their normal
habitat in a healthy individual but may do so in a different
environment.

is the number of animal in a population who develop a disease during a particular time period. It is an indicator of the spread of the
disease.

of a disease is the number of animals in a population who develop a disease at a specified time, regardless of when it first appeared. Prevalence takes into account both old and new cases.

Frequency of occurrence is another criterion that is used in the classification of diseases:

If a particular disease occurs
only occasionally

A disease constantly present
in a population

A population in a given area
acquire a certain disease in a relatively short period

An epidemic disease that occurs worldwide

Severity or Duration of a Disease

is one that develops rapidly but las ts only a short time

develops more slowly, and the body's reactions may be less severe, but the disease is likely to continue or recur for long periods

A disease that is mediate between acute and chronic is described as a

is one in which the causative agent
remains inactive for a time but then becomes active to produce symptoms of the disease

is one in which the invading microorganisms are limited to a relatively small area of the body.

microorganisms or their products are spread throughout the body by the blood or lymph

local infection enter a blood or lymphatic vessel and spread to
other specific parts of the body, where they are confined to specific areas of the body

is a toxic inflammatory condition arising from the spread of microbes,
especially bacteria or their toxins, from a focus of infection.

also called blood poisoning, is a systemic infection arising from the
multiplication of pathogens in the blood.

The presence of bacteria in the blood

refers to the presence of toxins in the blood

refers to the presence of viruses in blood

is an acute infection that causes the initial illness.

is one caused by an opportunistic pathogen after the primary infection has weakened the body's defenses

is one that does not cause any noticeable illness

patterns ofdiswase

makes the body more susceptible
to a disease and may alter the course of the disease

Give predisposing factoe

Development of Disease

is the interval between the initial
infection and the first appearance of any signs or symptoms.

is a relatively short period that follows the period of incubation in some diseases.

the disease is most severe

the signs and symptoms subside

the animal regains strength and
the body returns to its prediseased state. Recovery has occurred

Transmission of Disease

Animal to animal, Human to animal

Transmission of disease to humans

nonliving object.

General term for object involved in the spread of an infection is a

is the transmission of disease agents by a medium, such as water, food, or air

animals/arthropods that carry pathogens from one host to another

is the passive transport of the
pathogens on the insect's feet or other body parts

is an active process and is more
complex. The arthropod bites an infected person or animal
and ingests some of the infected blood

does
not show any evidence of bei ng present or incubating at the time of admission to a hospital; it is acquired as a result of a hospital stay

relating to illness caused by medical examination or treatment

Portals of entry

is a necessary step in
pathogenicity the attachment between pathogen and host is accomplished by means of surface molecules on the pathogen

surface molecules on the pathogen
called ________ that bind
specifically to complementary surface receptors on the cells of certain host tissues

Adhesins can be located:

is the capability or potential of a pathogenic agent to cause disease or harm the host

degree of toxicity or the injury-producing potential of a microorganism

are bacterial enzymes that coagulate (clot) the fibrinogen in blood.

a plasma protein produced by the liver, is converted by coagulases into
fibrin, the threads that form a blood clot.

are bacterial enzymes that break down fibrin and thus digest clots formed by the body to isolate the infection .

is another enzyme secreted by certain bacteria,
such as streptococci. It hydrolyzes hyaluronic acid, a type of
polysaccharide that holds together certain cells of the body,
particularly cells in connective tissue

produced by several species of Clostridium, facilitates the spread of gas gangrene. breaks
down the protein collagen, which forms the connective tissue
of muscles and other body organs and tissues

Process of alteration of pathogens can on surface antigens

pathogens secrete proteins called

are poisonous substances that are produced by certain microorganisms.

The capacity of microorganisms to
produce toxins is called

Toxins arc of two general types, based on their position relative to
the microbial cell:

are produced inside some bacteria as part of their growth and metabolism and are secreted by the bacterium
into the surrounding medium or released following lysis.

provide immunity to exotoxins.

Such altered exotoxins are called

Heart cells

Nerve cells

live cells

leukocytes

lining of the GIT

wide variety of cells

Types of exotoxin

cause lysis of host cells by disrupting their plasma membranes

By forming protein channels in the plasma membrane

disrupt the phospholipid portion of the membrane.

are antigens that provoke a very intense immune response

Diphtheria Toxin

Erythrogenic Toxins

Botulinum toxin

Tetanus Toxin

Vibrio Enterotoxin

Staphylococcal Enterotoxin

is an A-B neurotoxin; it acts
at the neuromuscular junction and prevents the transmission of impulses from the nerve cell to the muscle.

As a result, botulinum toxin
causes paralysis in which muscle tone is lacking

This A-B toxin reaches the central nervous system and binds to nerve cells that control the contraction of various skeletal muscles.

Toxin result in uncontrollable muscle contractions, producing the convulsive symptoms (spasmodic cont ractions) of tetanus, or

Subunit B binds to epithelial cells,
and subunit A causes cells to secrete large amounts of fluids and
electrolytes (ions).

produces a superantigen that affects the intestines in the! same way as Vibrio
enterotoxin.

are part of the outer portion of the
cell wall of gram-negative bacteria

release of endotoxin

Shock caused by bacteria is called

Gram-negative bacteria cause

Lab test for endotoxin The hemolymph (blood) of the Atlantic coast horseshoe crab, Limulus polyphemus, contains white
blood cells called amoebocytes, which have large amounts of a protein (lysate) that causes clotting.

portals of exit are the