Eukaryotic Microorganisms Flashcards
Nosocomial infections
infections contracted by individuals who went to the hospital for a different issue.
Three domains of life
Bacteria, eukarya, archaea
Hooke
Cell theory, saw cork cell. All things are composed of cells.
Leeuwenhoek
father of microbiology, built his own microscope, “wee little beasties”, identified microorganisms.
Louis Pasteur
Found link between viruses and disease. Solved France’s wine problem with bacteria and fermentation. Told them to pasteurize the grape juice first, hence the name pasteurization.
Koch
Germ theory. Discovered some microorganisms were detrimental to health. Tested on live animals with the tissue of those who had died from anthrax to find a link between them and disease. Showed bacterial-disease correlation.
Semmelweis
Hand washing, child bed fever
Lister
Very thorough in his disinfecting before-during-after surgeries and proved to scientific community that microbes are detrimental to human health.
Coccus
spherical
Arrangements
Diplo- 2
Strepto- “chain”
Staphylo- “grapes”
Bacillus
rod
Biofilm
bacteria covering a surface using capsules to stick
Spirillium, spirochete
corkscrew
All coccus and bacillus cells have:
cytoplasm, nucleoid, ribosomes, cytoskeleton, membrane
Some bacteria have:
cell wall, outer membrane, capsule, inclusions, plasmids, flagellum, endospores.
What is a capsule composed of?
carbohydrates, don’t stain, uses polysaccarides to fool immune system
Purpose of plasmids
gene pockets that are passed to other bacterial with beneficial traits such as antibiotic resistance.
What is the plasma membrane composed of?
Phospholipids in bilayers with proteins on surface for detection, transport, and communication.
What are cell walls made of?
peptidoglycan
What is the composition of peptidoglycan?
Strands of two carbohydrates: NAM and NAG connected together by covalent bonds. Multiple strands are connected together using amino acids.
Why is a cell wall like a cage?
It holds the plasma membrane in from expanding too much from osmotic pressure.
-Penicillin breaks down cell walls which make cells rupture from osmotic pressure.
Explain a Gram positive cell wall
Multiple layers of peptidoglycan stacked on top of one another and held together with techoic acid.
Explain a Gram Negative cell wall
Two membranes, inner and outer. The inner membrane is a phospholipid bilayer with a gap/buffer and then a single layer of peptidoglycan, followed by another filler and a phospholipid layer mixed with a layer of LPS on top.
What are the four steps of Gram staining?
- apply crystal violet
- apply grams iodine- helps crystals crystalize
- wash with alcohol- decolorizes gram negative
- . Secondary stain of safranin to stain gram negatives
What colors are the positive gram stain and which are the negative?
Purple=positive
Red/pink=negative
Flagella
Uses energy from ATP to spin flagella.
Monotrichous
one hair
lophitrichous
multiple at one end
Amphirichous
one at each end
pefitrichous
multiple on whole body
Run and tumble directions
Run= counterclockwise Tumble= clockwise
Chemotaxis
moving towards food and away from danger
Axial filaments
inside outer sheath, causes cell to move like a corkscrew
Fimbriae
Allows attachment to cells that are different
Pili/pilus
attach to bacteria and transfer plasmid
Ribosomes
produce proteins
Plasmids `
small circular strands of DNA
Endospores
- Gram Positive
- Clostridium and Bacillus only two genra
- Protect against heat, dehydration, radiation
Sporulation
formation of endospore
Spore coat
Composed of peptidoglycan, comes from vegetative cell
Tetnis
Anaerobic, endospore in soil, deep wounds causes problems
Botulism
anaerobic, endospores in soil get on beans
What is a viruses main purpose?
to replicate
What main components to viruses Not have that makes them non-living?
No ATP or protein generating mechanisms. Cannot initiate chemical reactions on their own.
What is a viroid?
Virus outside of the cell
Two components all viruses have
Nucleic acids, protein coat
Some Viruses have:
envelopes which they take from their host cell
Three shapes of viral capsids:
Polyhedral-many faced cube
Helical-tube of protein
Combination- “Lunar model”
Name the six steps of animal virus replication:
1- Attachment 2- Entry 3- Uncovering 4- Synthesis 5- Assembly 6- Exit
What determines the host range and the type of cells that a virus can infect?
attachment proteins or spikes
How does entry of a virus occur?
penetration of a virus occurs by endocytosis or membrane fusion
What is the most critical step in animal virus replication?
attachment
What are the two ways that the new viruses can leave a cell?
Lysis- bursting of the cell, naked viruses
Budding- envelope is taken with as the virus slowly buds from cell.
Where is viral RNA replicated?
in the cytoplasm
Which RNA has to have an enzyme switch to turn into DNA?
- RNA (negative)
Retrovirus
HIV, can turn RNA to DNA and back again
Viroids
Infectious RNA, only in plants, no proteins, self replicating
Prions
infectious proteins, non-living, no nucleic acid, Kuru, long incubation periods, non-immune response inducing
