Prokaryotes Flashcards
Prokaryotes
-Exist almost everywhere, including places where ____________ cannot survive.
-Biomass outweighs all eukaryotes combined by at least ________.
-eukaryotes
-10x
Prokaryote Functions
-Break down organic material in dead plants and animals.
-Release ______ used by plants.
-Make _________ available to most life forms.
-O2 in atmosphere came from photosynthetic ___________.
-CO2
-Nitrogen
-Bacteria
Prokaryotes
Both __________ and __________ to humans.
-Important to produce some _______.
-Chemical reactions in industry.
-Used for pharmaceutical products
-Bioremediation of ___________ sites.
-Beneficial
-Harmful
-food
-polluted
Shared Characteristics of the 3 Domains: Bacteria, Archaea, Eukarya
-____________
-____________
-Plasma membrane
-DNA
-Ribosomes
Archaea and Bacteria Characteristics:
-___________
-No Membrane-bound organelles
-No nucleus
Bacteria and Archaea:
-____________
-No _________
-No ____________
-Prokaryotes
-nucleus
-membrane-bound organelles
Domain Bacteria and Archaea
-___________
-__________ ____________
-No ____________
-No ________-________ ___________
-PROKARYOTES
-Unicellular
-Asexual reproduction
-No Nucleus
-No membrane-bound organelles
Domain Eukarya
- ____ or _________________
-___________ or __________ _____________
-____________
-_________-__________ __________
-EUKARYOTES
-Uni or multicellular
-sexual or asexual reproduction
-Nucleus
-Membrane-bound organelles
Prokaryotic Genomes
-Prokaryotes genomes _________, simpler than eukaryotes
-1/1000 as much DNA as a eukaryote
-5,000 genes vs. 50,000 in eukaryotes
-DNA condensed in ________ ________ of cytoplasm.
-similar to nucleus but __ ________
-Single, circular, double-stranded DNA chromosome.
-smaller
-nucleoid region
-no membrane
Prokaryote Reproduction
-Prokaryotes grow and adapt _______.
-Reproduce ______ _________ via ______ _______.
-No _______
-A single cell in favorable conditions will produce a colony of offspring (10^12 cells in 24 hrs!)
-rapidly
-mostly asexually
-binary fission
-Meiosis
Binary Fission in Prokaryotes
1. Circular __________ replicates
2. Copies of DNA _________ as cell enlarges.
3. _______ ________ and ____ _____ separate into two cells.
-chromosome
-separate
-Plasma membrane
-cell wall
Prokaryote Reproduction
-Because of _______, microbial growth is ____________.
-__________ occur more often!
-fission
-exponential
-mutations
When conditions unfavorable, some bacteria form __________ (dormant condition).
-Cytoplasm and chromosome _________.
-Encased by ___ layers.
Resistant to:
1. ______
2. Drying
3. ___________
4. Antibiotics
5. Various chemical disinfectants
-Can survive for ____________ in this dormant state!
-endospores
-dehydrate
-3
-heat
-radiation
1000s of years
Genetic Diversity?
-______ ________ but….
-Several mechanisms to combine genes between individuals
-These are called __________ ______ __________.
-Allows genetic transfer between prokaryotes:
1. Transformation: a cell absorbs and integrates fragments of ___ from the ___________.
2. Conjugation: one cell directly transfers genes to ________ ____.
3. Transduction: ________ transfer genes between prokaryotes.
-Lacks meiosis
-horizontal gene exchange
-DNA
-Environment
-another cell
-viruses
Domain Bacteria
Bacteria differentiated with Gram Stain
-Gram positive
-Retain dyes (purple and red)
- Appear _________
- _______ cell wall
-Gram negative
- Only retain red dye
-Appear ______
-_____ cell wall
-purple
-thick
-pink
-thin
Gram-positive (Gram+) bacteria-
________, thicker cell walls, large amounts of peptidoglycan in a thick cell wall.
-simpler
Gram-negative (Gram-) bacteria-
_____ _______, less peptidoglycan, thinner cell wall.
-Outer membrane __________ cell wall.
-Contains lipopolysaccharides (carbohydrates bonded to lipids)
- extra layer in cell wall.
-more complex
-outside
Among pathogenic bacteria
-Gram- more ____________ than Gram+
-Outer membrane protects _________ pathogens from defenses (immune system) of their hosts.
-Gram- bacteria more ___________ than Gram+ to antibiotics
-Outer membrane impedes entry of antibiotics
-threatening
-Gram-
-resistant
Bacteria also differentiated by 3 basic shapes
1. Cocci- ________
2. Bacilli- _____
3. Spirilli- ______
- round
- rod
- spiral
Many prokaryotes are motile
About half of all prokaryotes are capable of movement.
*Flagella
-Scattered over the entire surface
-Concentrated at ____ or _____ ____
-______________ for different organisms
-one or both ends
-Characteristic
Domain Bacteria
-Outnumber all other organisms on Earth
-__________ species identified
-Habitats range from land, aquatic, to parasitic
-Remarkable metabolic diversity allows them to live almost anywhere.
-Biomass outweighs all eukaryotes combined by at least _________.
Significance to Humans
-Some cause ________________________
-MRSA
-Bacterial Meningitis
-Provide _________, chemicals and __________
-Fermented meat (salami)
-Lactobacillus and Streptococcus (both bacteria)
produce yogurt
-Geochemical processes (carbon and nitrogen cycles)
-Nitrogen fixation
-Photosynthesis
Cyanobacteria
-____________ bacteria
-________________________
-Called “blue-green algae”
-Maybe responsible for _____________ into the primitive atmosphere (3.5 BYA)
-Photosynthetic and unicellular or colonial
-Common in freshwater, moist soils, oceans,
bare rock
Cyanobacteria
-Produce ___________ and ____________
-____________ are highly toxic
-____________ damage _________
-Low, chronic exposures may cause liver
cancer
