Bio 111 Final Flashcards
Bacteria
-prokaryotic cells
-lack nucleus
-unicellular
-microscopic
-dna strands free floating in center (look like nasty spaghetti)
-grown on nutrient agar plates
Cocci
-spherical bacteria
can grow in a diplococcus set
-can grow in a streptococcus chain
-can grow in a staphylococcus cluster
Bacilli
-rod shaped bacteria (oval-ish, like a pill)
-can grow in a bacili chain
Spirillum
-spiral shaped bacteria
-image example is short, loose spirals
Spirochaete
-corkscrew shaped bacteria
-image example is longer, tighter spirals
Vibrio
-‘comma’ shaped bacteria
-example image is brown
Gram Stain
-used to classify bacteria by cell wall composition
-Gram negative bacteria are stained red/pink
-Gram positive bacteria are stained purple
Antibacterial Test
-used to test effectiveness of antibacterial solutions
-most effective antibiotic has largest zone of inhibition
-zone of inhibition is area around disk where bacteria is killed
-image has disk covered in brown bacteria
-little blue disk represents disk soaked in antibacterial substance
-zone of inhibition is white circle around disk
Bacteria Size
-micrometer
-Average 1 mm
Parts of Prokaryotic Bacteria Cell
-Capsule
-Cell Wall
-Cell Membrane
-Chromosome
-Plasmid
-Ribosome
-Inclusions
-Flagella
-Pili
Capsule
-outer covering
-protects bacteria
-protects from immune system
Cell Wall
-made of peptidoglycan bilayer
-maintains cell shape
-protects cell
-unique to bacteria
Chromosome
-DNA
-Single
-Circular
Plasmid
-not part of chromosome
-small circular DNA
Ribosome
-protein synthesis
-appear as dots within cell
Inclusions
-storage granules
-store excess nutrients
-store phosphorus
-store ATP
- store metachromatic granules
-gas (CO2) vacuoles
Flagella
-allow movement
-complex motor and hook components
-made of proteins
Pili
-used to attach to surfaces
Peptidoglycan
-network of sugar chains
-linked to amino acids
-makes up bacteria cell wall
Gram-Positive Bacteria
-have thick cell wall
-large amounts of peptidoglycan
-stain purple
Gram-Negative Bacteria
-have thin cell wall
-less peptidoglycan
-toxic outer membrane
-stain red
Cell Membrane
-functions in energy production
-contains Electron Transport Chain
-phospholipid bilayer
Cytoplasm
-fluid interior of cell
-mostly water
Nucleoid
-centrally located DNA
-single circular chromosome
-DNA contains all genes
Gas Vacuoles
-CO2
-allows aquatic bacteria to float
-important for photosynthesis
-direct sunlight not filtered
Cyanobacteria
-bacteria that supply world with oxygen through photosynthesis
Bacteria Reproduction
-binary fission
-double in length
-DNA doubles
-Cell splits in half
Steps of Binary Fission
-DNA duplicates and attaches to membrane
-Membrane grows, DNA moves to opposite sides
-Cell divides at mid cell
-cells separate
Types of Symbiotic Relationships
-Mutualism
-Commensalism
-Parasitism
Mutualism
-both organisms benefit
-example: gut bacteria
Commensalism
-neither organism benefits or is harmed
-example: skin bacteria
Parasitism
-one organism benefits, one is harmed
-example: tuberculosis bacteria in lungs
Mutualistic Bacteria of Human Body
-intestines home to ~500-1000 species of bacteria
-many break down undigested food
-signal blood vessel formation to absorb nutrients from food
-keep bad bacteria out
-antibiotic kill good and bad bacteria
Biotechnology
-use of bacteria to make products
-ex: swiss cheese, apple cider vinegar, yogurt, soy sauce, nail polish remover
Genetic Engineering
-genetically engineered microorganisms
-used to produce human proteins
-ex: insulin
Steps of Genetic Engineering
-cut plasmid with restriction enzymes
-insert foreign gene into plasmid
-creates recombinant plasmid with foreign gene
-bacteria with new gene grown/produced from host bacteria
Restriction Enzyme
-molecular scissors
-cut DNA
Genetically Modified Plants
-may increase quality/quantity of food
Pest Resistant Plants
-plants engineered to kill insects
-engineered to make BT Toxin
-BT toxin fatal to insects, harmless to animals and plants
BT Toxin
-produced by bacteria bacillus thuringiensis (found in soil)
-toxic to insects; dissolves their gut
Bioremediation
-using microbes to clean up pollutants
-clean up oil spills
-bacteria degrade organic matter in sewage
-bacteria detoxify oil and mercury
Types of Spirillium Bacteria (spiral)
-Treponema pallidum (syphilis)
-Borrelia burgdorferi (lyme disease)
-typhoid fever (waterborne; vibrio)
-cholera (waterborne; vibrio)
Types of Bacillus Bacteria (rod)
-H. Pylori (ulcers)
-E. coli
-tetanus
Types of Cocci Bacteria (spherical)
-Streptococcus (strep throat)
-Staphylococcus (staph infection; MRSA)
-Chlamydia
Viruses
-cause infections in animals, plants and bacteria
-must infect living cells
-not considered living
-take over host cell’s machinery to make new viruses
-poison
-measured in nanometers
-smaller than bacteria
Bacteriophages
-phages
-viruses that infect bacteria
Virus Structure
-genes
-DNA in bacteriophage
-DNA or RNA in animal viruses
-protein coat that surrounds DNA
Three Basic Virus Shapes
-Helical
-Polyhedral
-complex
Helical
-spiral
-tube-like
-long rods
-ex: ebola, tobacco mosaic virus
Polyhedral
-dome like
-many sided
-one has 20 sides
-ex: common cold, chicken pox, flu, H1N1 (bird flu/swine/flu), SARS, Covid 19, HPV, Herpes, HIV, Rotovirus
Complex
-varied shapes
-head contains DNA
-tails are proteins for attachment to host cell
-ex: small pox, rabies
Bacteriophage Structure
-head; contains DNA
-tail; make of tail fibers and base plate, attached to host cell
-made of protein
Animal Virus Structure
-genes; DNA or RNA
-Capsid
-Envelope
-Spikes
Animal Virus Capsid
-protein coat
-make of capsomeres
-capsomeres are small subunits that are building blocks of capsid
Animal Virus Envelope
-phospholipid bilayer
-only on some viruses
-derived from membrane of host cell
Enteric Virus
-ingested
-causes gastroenteritis (inflammation of stomach and intestines)
Respiratory Virus
-inhaled
-respiratory infections
Sexually Transmitted Virus
-transmitted sexually
-lesions in genital tract
Zoonoses
-transmitted from animal to human
-ex: mosquito
Bacteriophage Replication
-Lytic Life Cycle
-Lysogenic/Latent Life Cycle
Lytic Life Cycle
-bursts out of cell upon production of new virus within host cell
Lysogenic Life Cycle
-aka latent life cycle
-phage genes inserted into host chromosome
-remains dormant for period of time
-replicates virus genome without destroying host cell
-viral DNA incorporated into host cell chromosome
-is permanent
-results in prophage/provirus
Steps of Lytic Life Cycle
-Attachment
-Entry
-Synthesis
-Assembly
-Release
Attachment
-Phage attaches to bacteria
Entry
-phage releases lysozyme
-digests cell wall
-injects DNA into bacteria
Synthesis
-gene expression
-replication of DNA
-production of head and tail
Assembly
-phage parts put together
-forms new phage
Release
-lyse/burst out of host cell
Retrovirus
-use reverse transcription
-copy their RNA to DNA
-inserts into human chromosome
-becomes provirus
-permanent
-ex: HIV
HIV
-retrovirus
-RNA virus
-causes AIDs
-destroys T cells
-renders immune system ineffective at clearing pathogens
-must bind to CD4 and CCR5 receptor proteins on membrane of T-cell in order to enter cell
Viroids
-small infectious particles
-RNA only
-infect plants
Prions
-small infectious particles
-Protein Only
-change shape of brain proteins
-causes Mad Cow Disease
-slow acting
-virtually indestructible
-converts normal proteins into prion version
