microbiology introduction Flashcards
7 groups of microorganisms
bacteria
archaea
fungi
protozoa
algae
small multicellular animals
viruses(?)
prokaryotic cell
-no nucleus
-no membrane-bound organelles
-circular chromosomes
-asexual reproduction (binary fission)
-unicellular/colonial
-usually small
bacteria
-peptidoglycan cell wall (some species lack cell wall)
-a few species are harmful to humans; most are neutral or beneficial
what is the bacterial cell wall made of?
peptidoglycan
arcaheans
-non-peptidoglycan cell wall
-ribosomal structure closer to eukaryotes
-often found in extreme environments
-none associated with disease
i..e methanogens (animal GI tract), extreme halophiles (super salty environment)
5 eukaryotes
protists
algae
fungi
plants
animals
2 prokaryotes
bacteria
archaea
prokaryotes vs eukaryotes:
organization
size
type of nucleus
DNA
cell movement
membrane bound organelles
organization: usually unicellular vs unicellular, multicellular, colonies
size; smaller vs bigger
type of nucleus: none (its DNA housed in a ‘nucleoid’ region) vs proper nucleus with a double membrane
DNA: usually circular, vs linear chromosomes
cell movement; flagella (flagellin protein) vs cilia, pseudopodia
membrane bound organelles: none vs many
fungi
-absorptive heterotroph
-cell wall made of chitin
-uni or multicellular
-hypae (rods) for bisexual and asexual spores to reproduce
or reproduce by budding cells
what is fungi cell wall made of
chitin
fungi, protozoans, animals, algae :
ingestive heterotroph or absorptive heterotroph or photosynthetic autotroph
fungi- absorptive
protozoans- ingestive
animals- ingestive
algae- photosynthetic autotroph
ingestive vs absorptive heterotrophs
Fungi are absorptive heterotrophs: they secrete digestive enzymes that break down polymers to monomers which are absorbed across the cell wall and cell membrane.
-i.e. absorb pre-digested nutrients
Animals are ingestive heterotrophs: they eat their food and digest it in a compartment within their bodies.
protozoans
NOT PROTISTS
-single cells eukaryotes
-ingestive heterotrophs (like animals)
-often sorted according to motility: cilia, flagellum, pseudopodia
how protozoans can move (3)
cilia, flagellum, pseudopodia
algae
-uni or multicellular eukaryotes
-photosynthetic autotroph
-categorized on the basis of their pigmentation and the composition of their cell walls
-multicellular: seaweed and kelp; no roots; all tissues are photosynthetic
animals
ingestive heterotroph
-adults visible but larvae are microscopic
hippocrates
400BC; link between environment and disease
-Thucydides notes plague survivors cannot get the same disease twice
Robert Hooke (1650s)
founder of cell biology
-introduced the notion that cells were the fundamental unit of life
-coined the term “Cell” due to resemblance of honeycomb cells
who was the founder of cell biology
Robert hooke
who was the founder of microbiology
antonie van leeuwenhoek 1670s
antonie van leeuwenhoek 1670s
founder of microbiology
-first reported existence of most types of microorgansims
antonie van leeuwenhoek discovered what?
protists: any eukaryotic organism that is not an animal, plant or fungus
also vertebral sperm cells
-spermatozoa
-muscle fibers
-RBCs
who discovered protists
antonie van leeuwenhoek
who discovered sperm cells
antonie van leeuwenhoek