Viruses & BacteriaViruses & Bacteria
Chapter 17Chapter 17
Biology 11Biology 11Presentation put together by Mandie Lynn WallsPresentation put together by Mandie Lynn Walls
What are Viruses
A virus is a non-cellular particle made up of genetic material and protein
that can invade living cells.
Escherichia Coli BacteriumEscherichia Coli Bacterium
E. coli is a bacterium. That is a crude cell, it is not a virus E. coli is a bacterium. That is a crude cell, it is not a virus because viruses are protein containers with DNA cores or because viruses are protein containers with DNA cores or
RNA cores.RNA cores.
E. Coli and the E. Coli and the BacteriophageBacteriophage
What it looks like in real lifeWhat it looks like in real life
The Structure Of a VirusThe Structure Of a Virus Viruses are Viruses are
composed of a core composed of a core of nucleic acidof nucleic acid
The Nucleic acid core The Nucleic acid core is surrounded by a is surrounded by a protein coat called a protein coat called a capsidcapsid
The Nucleic core is The Nucleic core is either made up of either made up of DNA or RNA but DNA or RNA but never bothnever both
Vaccines Vaccines
►Viruses grown on chicken embryos are Viruses grown on chicken embryos are attenuated vaccinesattenuated vaccines
►Another type of vaccine is made by heat Another type of vaccine is made by heat killing the virus killing the virus
A typical, "minimal" retrovirus consists of: •an outer envelope which was derived from the plasma membrane of its host •many copies of an envelope protein embedded in the lipid bilayer of its envelope •a capsid; a protein shell containing •two molecules of RNA and •molecules of the enzyme reverse transcriptase
Prokaryotes
Cells that do not have a nucleus
Exist almost every where on earth
Grow in numbers so great you can see them with the unaided eye
Are placed in either the Eubacteria or the Archebacteria Kingdoms
Make up the smaller of the two kingdoms
EubacteriaEubacteriaMake up the larger of Make up the larger of the two prokaryote the two prokaryote kingdomskingdoms
Generally are Generally are surrounded by a cell surrounded by a cell wall composed of wall composed of complex complex carbohydratescarbohydrates
CyanobacteriaCyanobacteria Photosynthetic Photosynthetic
bacteriumbacterium Bluish-greenish colorBluish-greenish color Contain membranes Contain membranes
that carry out the that carry out the process of process of photosynthesisphotosynthesis
Do not contain the Do not contain the same type of same type of chloroplasts as plants chloroplasts as plants dodo
This bluish-greenish This bluish-greenish algae can be found algae can be found nearly everywhere on nearly everywhere on earth.earth.
Can survive in Can survive in extremely hot extremely hot environments and even environments and even extremely cold extremely cold environmentenvironment
ArchaebacteriaArchaebacteria Lack important Lack important
carbohydrate found carbohydrate found in cell wallsin cell walls
Have different lipids Have different lipids in their cell in their cell membranemembrane
Different types of Different types of ribosomesribosomes
Very different gene Very different gene sequencessequences
Archaebacteria can Archaebacteria can live in extremely live in extremely harsh environmentsharsh environments
They do not require They do not require oxygen and can live oxygen and can live in extremely salty in extremely salty environments as well environments as well as extremely hot as extremely hot environments.environments.
Identifying ProkaryotesIdentifying ProkaryotesCell ShapeCell Shape
Cell WallCell Wall
MovementMovement
Bacterium Shapes
Cocci~ Sphere shaped bacteria
Bacillus~ Rod shaped bacteria Spirrillium ~ Spiral shaped
bacteria Flagella~ Leg-like structures
that help to propel the bacterium.
Cellular WallsCellular Walls Chemical nature of a cell wall can be determined Chemical nature of a cell wall can be determined
by Gram Stainingby Gram Staining By finding out what color the cell produces when By finding out what color the cell produces when
it is gram stained you can figure out the type of it is gram stained you can figure out the type of carbohydrates in the cell wallcarbohydrates in the cell wall
Movement
• Flagella ~ Tail like structure the whips around to propel the bacterium
• Cillia ~ Miniature flagella surround the cell that help to “swim”
• Non motile ~ Sticky cillia like structures that keep the bacterium from moving
Bacteria and their Bacteria and their energyenergy
AutotrophsAutotrophs ChemotrophsChemotrophs HeterotrophsHeterotrophs
AutotrophsAutotrophs Make their own Make their own
energyenergy Using Solar energyUsing Solar energy Eg. CyanobacteriaEg. Cyanobacteria
ChemotrophsChemotrophs
Make own EnergyMake own Energy Using Chemical energyUsing Chemical energy Eg. ArchaebacteriaEg. Archaebacteria
Bacteria RespirationBacteria Respiration
Obligate AnaerobesObligate Anaerobes Facultative Facultative
AnaerobesAnaerobes
Obligate AerobesObligate Aerobes
Live without OxygenLive without Oxygen Can live with or Can live with or
without oxygenwithout oxygen Cannot live without Cannot live without
oxygen. oxygen.
Bacteria ReproductionBacteria Reproduction
Binary FissionBinary Fission ConjugationConjugation Spore FormationSpore Formation
Conjugation
A type of Bacteria Sex
Two organism swap genetic information, that contains the information such as a resistance to penicillin
Spore Formation: EndosporeSpore Formation: Endospore A type of dormant cell A type of dormant cell Exhibit no signs of lifeExhibit no signs of life Highly resistant to Highly resistant to
environmental stresses such environmental stresses such as:as:
-High temperatures-High temperatures-Irradiation-Irradiation-Strong acids-Strong acids-Disinfectants-Disinfectants
Endospores are formed by Endospores are formed by vegetative cells in response to vegetative cells in response to environmental signals that environmental signals that indicate a limiting factor for indicate a limiting factor for vegetative growth, such as vegetative growth, such as exhaustion of an essential exhaustion of an essential nutrient. nutrient.
SymbiosisSymbiosis
Close relationship Close relationship between to species in between to species in which at least one which at least one species benefits from species benefits from the otherthe other
Live together for LIFELive together for LIFE
Mutualism
Symbiosis in which two of the species live together in such a way that both benefit from the relationship
Eg. E-coli
Nitrogen Fixations Nitrogen Fixations
Process by which nitrogen in the Process by which nitrogen in the atmosphere is converted into a form that atmosphere is converted into a form that can be used by living things can be used by living things