Chapter 13. Microbe-Human Interactions: Infection, Disease, and Epidemiology

Microbial is the situation in which microorganisms compete for survival in a common environment and where resident microorganisms take actions that inhibit or destroy intruder microorganisms.

antagonism

The microbial groups that make up the normal flora of the skin consist primarily of and yeasts.

bacteria

To cause actual damage to a host, a microbe must ______.

induce an injurious immune response produce toxins that destroy tissue

Many resident microbiota have the potential to cause , if the microorganisms spread beyond their natural microhabitat within the body or if the host's immune system is compromised.

infection

The condition in which pathogens enter, establish, and multiply in the human host is referred to as a(n) ______.

infection

The invasion and multiplication of a pathogen in the human host is referred to as a(n) .

infection

he human is the collective total of genetic material from all the normal resident microbiota that can live in or on the body.

microbiome

Long term microbial inhabitants of the skin and exposed mucosa, that participate in mutual or commensal association without generally causing disease in the host, are called normal resident

microbiota

The human microbiome is the collective total of all DNA sequences from the ______.

normal resident microbiota

The only areas of the gastrointestinal tract that harbor numerous permanent resident microbes are the ______.

oral cavity, large intestine, rectum

The relationship between a pathogen and its host is best described as ______.

parasitic

Any biological agent that causes disease is called a(n) ______.

pathogen

In many cases, normal biota can benefit the human host by ______.

preventing the overgrowth of potentially harmful biota

Microorganisms that survive the body's defenses and become permanently established in or on the body are called -_______microbes.

resident

The stable microbes that inhabit the skin and exposed mucous membranes on a permanent or long-term basis, and generally do not cause disease are referred to as ______ biota.

resident Reason: Also called normal or indigenous biota

The normal bacterial inhabitants of the human body can be referred to as:

resident microbiota normal microbiota commensals indigenous microflora normal flora

The largest number of pathogens enter the body through the

respiratory

Microbes with ______ infectious doses are usually more virulent.

small

To establish itself in a host, a microbe must ______.

survive immune system defenses be able to adhere to host tissue utilize a portal of entry

Biological agents that can cause disease in healthy people with normal immune defenses are known as ________ pathogens.

true

pathogen is a biological agent that is capable of causing infection and disease in healthy persons with normal

true/primary

A factor is any characteristic or structure of the microbe that contributes to the infection or disease state.

virulence

The of a particular microbe is determined by its ability to establish itself in the host and cause damage.

virulence

of a particular microbe is determined by its ability to establish itself in the host and cause damage.

virulence

Which step is NOT directly required to cause actual damage to the host?

Avoid the host immune defenses

Pathogens enter the skin through which means?

Bites of other organisms Breaks in the skin Digestive enzymes creating passage

The cavity, large , and are the only areas of the GI tract that harbor permanent resident microbes. All of the other sections of the GI tract only harbor transient microbes. Listen to the complete question

Blank 1: oral or buccal Blank 2: intestine Blank 3: rectum or colon

The first microbes to colonize the upper respiratory tract are _________ streptococci.

Blank 1: oral or hemolytic

The first microbes to colonize the upper respiratory tract are

Blank 1: oral or hemolytic streptococci

Resident microbiota can benefit the human host by ____ the overgrowth of _______ microorganisms.

Blank 1: preventing, stopping, or inhibiting Blank 2: harmful, pathogenic, or bad

Which of the following is NOT a portal of entry?

Circulatory system

Which of the following is NOT a means by which pathogens enter the skin?

Diffusion across the stratum corneum

The main portals of entry include

Gastrointestinal tract, Urogenital tract, Respiratory tract, Skin

Which body sites usually do NOT have a resident microbial population?

Inner ear canal Muscles

Which general area of the body does NOT support resident biota?

Internal body fluids Internal tissues, organs, and body fluids without contact to the outside environment are generally microbe free.

Which two factors determine the virulence of a particular pathogen?

Its ability to cause damage to the host tissues Its ability to establish itself in the host

Which of the following indicates a relationship in which resident microorganisms prevent the overgrowth of intruder microorganisms when competing for survival in a common environment?

Microbial antagonism

Which are considered typical residents of the urethra?

Nonhemolytic streptococci Staphylococcus Corynebacterium

pathogenic

Pathogenic biota are disease causing microbes and are not usually long-term or permanent residents of the body.

is a broad concept that describes an organism's potential to cause infection or disease.

Pathogenicity

Which of the following steps is NOT required for a microbe to establish itself in a host?

Produce toxins or induce a damaging host response

If the inoculum is much larger than the infectious dose, what may occur?

Rapid onset of disease

Which are examples of normal flora of the skin?

Staphylococcus Propionibacterium Corynebacterium

Which of the following are the most common members of the normal flora of the mouth?

Streptococcus salivarius Streptococcus sanguis Streptococcus mitis

Inhabitants of rest tract

Streptococcus species Neisseria species Haemophilus Staphylococcus aureus

The human body usually supports resident biota in which of the following areas?

Tissues with contact to outside Body fluids in exposed body cavities

Which term is NOT used to refer to the normal microbes that inhabit the human body and usually do not cause disease?

Transient biota

transient

Transient biota are not long-term or permanent residents of the body.

Which locations are well-established sites harboring resident microbiota?

Upper respiratory tract Various parts of gastrointestinal tract External genitals External ear canal

Pathogenicity is ______.

a broad concept that describes an organism's ability to cause disease