Micro Lecture Test

viruses were called filterable because fluid remained infectious after passing through filters designed to trap…

bacteria

select all that apply to viruses:

aceullular, obligate intracellular parasites

viruses are typically in what size range?

20-450 nm

all viruses have an envelope outside their capsid. TRUE OR FALSE

false

_ are proteins that can be found projecting from the viral capsid

spikes

select all of the following that are typical virus shapes:

complex, helical, icosahedral

_ sense RNA genomes can be directly translated into proteins

positive

viral nucleic acid types include which of the following?

single-stranded DNA, single stranded RNA, double stranded DNA, double stranded RNA

infectious protein particles are called:

prions

the adeno associates virus and the delta agent are prions. TRUE OR FALSE

false

what type of phage enters an inactive prophage stage?

temperate

reverse transcriptase synthesizes…

viral DNA from RNA

put the phases of viral replication in order

adsorption, penetration/uncoating, synthesis/assembly, release

the adeno associated virus AAV and the delta agent are prions. TRUE OR FALSE

false

which of the following is not associated with every virus?

envelope

host range is limited by the…

type of host cell receptors on cell membrane

nonenveloped (naked) viruses release by budding from the host cell. TRUE OR FALSE

false

select all of the following that are cytopathic effects.

rounding of cells, inclusions form in cytoplasm, syncytia

a virus that causes cancer would be termed

oncogenic

lysogeny refers to….

the viral genome inserting into bacterial host chromosome

when a bacterium acquires a trait from its temperate phage, it is called _

lysogenic conversion

growing viruses in cell culture would be the…

in vitro method

Viruses are considered ultramicroscopic because they typically range in size from 2 mm to 450 mm. TRUE OR FALSE

false

the term infection refers to

pathogens penetrating host defenses

A fully formed virus that can cause an infection in a host cell is called a virion. TRUE OR FALSE

true

Viruses with _____-sense RNA contain the correct message for translation, while viruses with _____-sense RNA must first be converted into a correct message.

positive;negative

The primary purpose(s) of viral cultivation is/are to _______.

all are correct

Viruses acquire envelopes around their nucleocapsids during ______.

release

Mammalian viruses capable of starting tumors are ______.

oncogenic viruses

Viruses that infect bacteria are specifically called ______.

bacteriophages

Early viral researchers called viruses filterable because they noticed that infectious fluid remained infectious, even after passing through filters that were designed to catch __________________.

bacteria

A/an _______ is the protein shell around the nucleic acid core of a virus.

capsid

Helical and icosahedral are terms used to describe the shape of a viral ______.

capsid

A common method for cultivating viruses in the lab is to use *in vitro* systems called _____ cultures.

cell

Uncoating of viral nucleic acid _______.

all are correct

Persistent viruses that can reactivate periodically are ______.

chronic latent viruses

The event that occurs in bacteriophage multiplication that does not occur in animal virus replication is ______.

injection of only the viral nucleic acid into the host cell

the effect of beneficial microbes of normal biota against invading microorganisms is

microbial antagonism

the minimum number of microbes required for an infection to proceed

infectious dose

the greatest number of pathogens enter the body through the:

respiratory system

select all that are virulence factors

toxins, exoenzymes, capsules

an endotoxin is:

indicative of gram-negative bacterial infection

what would be the portal of exit for a disease like malaria spread by mosquitos

blood

put the 4 steps of infection in order

incubation, prodromal, acute, convalescent

latency is a dormant stage of infectious agent. TRUE FALSE

true

the study of the frequency and distribution of a disease in a defined population is:

epidemiology

if a vector such as a fly spreads a pathogen by carrying it on its feet, it is referred to as mechanical transmission. TRUE FALSE

true

the dried residues of fine droplets from mucus or saliva that harbor and transmit pathogens are…

droplet nuclei

an epidemic that spreads worldwide:

pandemic

john snow traced a london outbreak of cholera to a pump on broad street, the cholera outbreak was an example of…

common-source epidemic

An infectious agent already existing on or in the body is called ______.

endogenous

The holobiont is the human body plus the nutrients it currently carries. TRUE OR FALSE

false

A fetus can get an infection when a pathogen in the mother's blood is capable of crossing the placenta to the fetal circulation and tissues. TRUE OR FALSE

true

Virulence factors include all of the following except ______.

ribosomes

The time from when pathogen first enters the body and begins to multiply, until symptoms first appear is the ______.

incubation period

These infections come on rapidly and have short-lived effects.

acute infections

Someone who inconspicuously harbors a pathogen and spreads it to others is a _______.

carrier

Reservoirs include ______.

all are correct

The total number of existing cases with respect to the entire population is the _______ of a disease.

prevalence

if a disease is required by law to be reported to the CDC, it is a :

notifiable infectious disease

Under certain circumstances, a person's resident biota can act as opportunistic pathogens. TRUE FALSE

true

It is now being proposed, that certain sites that were once thought to be sterile, like the lungs for example, could harbor some microbiota. TRUE FALSE

true

The skin is a very tough barrier that few microbes can penetrate. TRUE FALSE

true

Which of the following is not a structure used for bacterial adhesion?

cilia

Septicemia means that a pathogen is present and multiplying in the blood. TRUE FALSE

true

This is when an infection spreads to several sites and tissue fluids, usually in the bloodstream.

systemic infection

The dried residues of fine droplets from mucus or saliva that harbor and transmit pathogen are ________.

droplet nuclei

An infection acquired during hospitalization is referred to as

HAI

Everyone who ate the crab cakes at a large fund raising dinner got sick. This is an example of a ________ epidemic.

point-source

Since the 1970s, approximately 40 new infectious disease agents have been discovered, including SARS, chikungunya and Zika. The ability of these agents to spread rapidly and cause global concern is due to all of the following except _______.

communities are becoming more sparsely populated

The term infection refers to _______.

pathogens penetrating host defenses

The Human ______________________ Project studies the microbes humans harbor and how they interact with us and impact our health.

microbiome

An example of an epigenetic change is ______.

a microbe that can induce changes in host DNA, resulting in suppression of defenses or weakening of individual cells

Latency is a dormant state of an infectious agent. TRUE FALSE

true

The term _______ refers to the presence of small numbers of bacteria in the blood.

bacteremia

An animal, such as an arthropod, that transmits a pathogen from one host to another is a ________.

vector

Animals that participate in the life cycles of pathogens and transmit pathogens from host to host are ______.

biological vectors

Lymph moves in two directions, both towards and away from the heart. TRUE FALSE

false

Which gland shrinks in size during adulthood and has hormones that function in maturation of T lymphocytes?

thymus

The body region where a ciliary escalator helps to sweep microbes trapped in mucus away from that body site is the ______.

respiratory tract

Each of the following are benefits of fever except______.

it increases the availability of iron

One of the major differences between the first and second line of defense is that______.

the first line defenses are anatomical barriers whereas the second line defenses are non-specific mechanisms like inflammation

the effect of beneficial microbes of normal biota against invading microbes is called

microbial antagonism

a disease that has a steady frequency over time in a particular geographic location

endemic

various bacterial enzymes that dissolve fibrin clots are

kinases

_ are toxins that cause the immune system to overreact, leading to damage of the host tissue

superantigens

when you are vaccinated against a virus you start producing antibodies. this is an innate immune response. TRUE FALSE

false

which of the following is considered to be an organ or tissue that performs lymphoid functions?

spleen, thymus, lymph nodes

neutrophils, eosinophils, and basophils are called _ because they have prominent cytoplasmic inclusions

granulocytes

the main function of the mononuclear phagocyte system is to provide:

provides a passageway within and between tissues and organs

keratin is an important aspect of nonspecific defense because it

creates a physical barrier against pathogens

the normal human microbiota is considered part of the first line of defense because

microbial antagonism keeps potential pathogens in check

the chemical found in tears and saliva that hydrolyzes the peptidoglycan in certain bacterial cell walls is

lysozyme

these are receptors on the surface of immune cells that recognize and bind to PAMPs

PRRs

chief functions of inflammation:

start tissue repair, destroy microbes and block their further invasion, mobilize and attract immune components to injury site

select all that apply to complement:

acts as a cascade reaction, composed of atleast 30 blood proteins

A negative RNA virus must first ________.

synthesize a positive RNA copy of its genome to be used as mRNA to make proteins.

Freshly isolated animal tissue that is placed in a growth medium and allowed to produce a cell monolayer is referred to as a/n _____ cell culture.

primary

Viruses acquire envelopes around their nucleocapsids during ______.

release

An infectious agent already existing on or in the body is called ______.

endogenous