Chapter 42: The Immune System

a general terms describing microorganisms and non-living microscopic particles that cause disease/illness to its host

pathogen

bacteria, fungi, and parasites are examples of what types of pathogens?

living organisms

viruses and prions are examples of what types of pathogen?

non-living infectious “particles”

a non-living infectious particle that has an absense of organelles, and can’t generate or store energy is a ___

virus

true or false: viruses only have single stranded DNA that codes for proteins required to assemble virions

false. viruses can have single or double stranded DNA, or RNA that codes for proteins required to assemble virions

the protein shell that encapsulates the viral genome, acting as protection

capsid

true or false: some animal viruses have a lipid bilayer membrane around the nucleic acid and capsid

true

“virus fuses to host cell” describes which step of the virus life cycle?

step 1

“virus RNA, reverse transcriptase, integrase, and other proteins enter out cell” describes which step of the virus life cycle?

step 2

true or false: viral DNA is formed by reverse transcription in step 4 of the virus life cycle

false. viral DNA is formed by reverse transcription in step 3 of the virus life cycle?

true or false: viral DNA is transported across the nucleus and integrates into the host cell in step 4 of the virus life cycle

true

during step 5 of the virus life cycle, new viral RNA is used as genomic RNA and to make ___

viral proteins

during step 6 of the virus life cycle, new viral RNA and proteins move to the cel surface, and a new ___ forms

immature virus

during step 7 of the virus life cycle, the virus matures when ___ releases the proteins for maturation

protease

true or false: viruses can replicate without a host; thus, they’re considered alive

false. viruses cannot replicate without a host; thus, they are not considered alive

non-living infectious particles that cause neurodegeration are ___

prions

what disease was caused by prions in the early 80s in cows, and early 90s in humans?

Mad Cow Disease

Variant Creutzfeldt-Jakob disease (vCJD) was the ___

first human case of prions

true or false: prions look like misfolded brain proteins, and have the capacity of changing normal-shaped proteins into abnormal shapes

true

prions become self-propagating, filling neurons with debris, which leads to ___

cell death

defense mechanisms that keep pathogens out are ___

physical/chemical barriers

this type of physical/chemical barrier has multiple layers, constantly renewed cells, an acidic environment, and antimicrobial peptide

skin

these types of physical/chemical barriers have lysozyme, which cleaves chemical bonds in peptidoglycan

saliva, mucus, tears

this type of physical/chemical barrier has gastric acid

stomach

this type of physical/chemical barrier outcompetes bacterial pathogens for resources

commensal (resident) bacteria

nonspecific defense mechanisms make up the ___

innate immune response

recognizing and targeting specific pathogens are defense mechanisms that make up the ___

adaptive immune response