Unit 6- Chapters 18 and 19 Flashcards
Viruses, bacteria, viroids, and prions can all…
…cause infection
Virus
An infectious particle made only of a strand of DNA or RNA surrounded by a protein coat
Pathogen
any living organism or particle that can cause an infectious disease
same as infectious agent
Viroids
infectious particles that cause disease in plants
Prion
an infectious particle made only of proteins that can cause other proteins to fold incorrectly
Viruses differ in…
…shape and in ways of entering host cells
Viruses cause…
…two types of infections
Capsid
a protein shell that surrounds the genetic materail in a virus
Bacteriophages
viruses that infect bacteria
Lytic Infection
an infectious pathway in which the host cell bursts, releasing thenew viral offspring intho the host’s system
Lysogenic Infection
a phage combines its DNA into the host cell’s DNA
Prophage
the phage DNA inserted into the host cell’s DNA
Viruses cause many…
…infectious diseases
Vaccinesare made from…
…weakened pathogens
Epidemic
a rapid outbreak of an infection that affects many people
Vaccine
a substance that stimulates the body’s own immune response against invasion by microbes
retrovirus
a virus that contains RNA and uses an enzyme called reverse transcriptase to make a DNA copy
Prokaryots are widespread…
…on earth
Bacteria an archaea are…
…structually similar but have different molecular characteristics
Bacteria have variou strategies for…
…survival
obligate anaerobe
poisoned by oxygen
obligate aerobe
organisms that need oxygen
faculatative aerobe
organisms that can survive with and without oxygen
Plasmid
a small piece of genetic material that can replicate separately from the prokaryote’s main chromosome
Flagellum
a long, whip-like structure outside of a cell that is used for movement
conjugation
the process by which prokaryotes can exchange parts of their chromosome through a hollow bridge of pili formed to connect two or more cells
endospore
a specialized cell with a thick portective wall
Prokaryotes provide…
…nutrients to humans and other animals
Prokaryotes play important…
…roles in ecosystems
bioremediation
a process that uses microbes and other living things to break down pollutants
some bacteria cause…
…disease
antibiotics are used to fight…
…bacterial disease
Bacteria can…
…evolve resistance to antibiotics
Toxin
a poison released by an organism
Antibiotic
chemicals that kill or slowthe growth of bacteria
Protists can be…
…animal-like, plantlike, or funguslike
Protisit are difficult to…
…classify
protist
aeukaryots that is not an animal, a plant, or a fungus
animal-like protists move in…
…various ways
some animal-like protists cause…
…disease
protozoa
often used informally to describe the many phylaof animal-like protists
same as zooplankton
Pseudopod
“fake foot”
a temporary extension of cytoplasm and plasmamembrane that helps protozoa move and feed
Cillia
short, hairlike structures that cover some or all of cell surface and help the organism swim and capture food
plantlike protists can be…
…single-celled or multicellular
Many plantlike protists can reproduce both…
…sexually and a sexually
algae
photosynthetic plantlike protists
Slime molds and water molds are…
…funguslike protists
Slime molds
eukaryotic organisms that have both funguslike and animallike traits
water molds
funguslike protists that aremade up of branching strands of cells
Fungi are adpadted to absorb their food from…
…the environment
fungi come in many…
…shapes and sizes
fungi reproduce…
…sexually and asexually
chitin
a tough polysaccharide that is also found in the shells of insects and their close relatives
hyphae
bodies of multicellular fungi are made of long strands
mycelium
groups of hyphae in long tangles masses
fruiting body
a reproductive structure of a fungus that grows above ground
Mycorrhizae
mutualistic partnerships between fungi and the roots of certain plants
sporangi
spore-forming structures at thhe tips of their hyphae
Fungi may be…
…decomposers, pathogens, or mutalists
fungi are studied for…
…many purposes
lichen
a mutualistic relationship between a fungus and algae or phtosynthetic bacteria
