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microbiology ch11
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The three basic shapes of prokaryotic cells are


  1. spherical, or round (cocci)
  2. rod-shaped (bacilli) NOTE- coccobacillus are cells like an oval so between cocci and bacillus
  3. sprial (stiif - spirilla OR flexible - spirochetes)



ALL prokaryotes reproduce _________.  NONE reproduce ________.


All prokaryotes reporduce asexually.  None reporduce sexually.


What is the most common method of prokaryotic reproduction?


Binary fission -
  1. Cell replicates its DNA to form a daughter DNA
  2. Cell grows or elongates and the daughter DNA separates from the main DNA.
  3. Cell forms a wall between two DNAs
  4. Cell's new walls completely divides.
  5. Daughter cells may or may not separate.  Parental cell disappears with the formation of projeny.



Binary fission is the most common way prokaryotes reproduce asexually.  What are other ways prokaryotes reproduce?


  1. Budding.  An outgrowth of the original cell (a bud) receives a copy of the genetic material and enlarges.  Eventually the bud is cut off from the parental cell.
  2. Spore formation.  Spores develop into clones of original cell.
  3. Snapping division.  Only the inner portion of the cell wall is formed.  As daughter cell grows, the tension snaps the outer portion.



Three basic shapes of prokaryotes are cocci, bacillus, and spiral.  What are other shapes associated with prokaryotes?


  1. vibrios - slightly curved rods
  2. coccobacilli - between cocci and bacilli
  3. pleomorphic - having variable shape and size.



What are the five arrangements of prokaryotes?


  1. diplococci - cocci attached in pairs.
  2. streptococci - cocci attached in a long chain.
  3. tetrads - 4 cells attached in a cube.
  4. sarcinae - 8 cells attached in a cube.
  5. staphycocci - looks like a bunch of grapes.



In prokaryotes, how are endospores formed?


In Gram-positive bacteria Bacillus and Clostridium.


Name several reasons why endospores are important.


  1. They constitute a defensive strategy against hostile or unfavorable conditions.
  2. They are stable resting stages that barely metabolize and germinate only when conditions improve.



What is it about endospores that should NOT confuse you?


They are not reporductive spores found in algae and fungi. 

It is a vegetative cell that produces ONE endospore.


Arrangements of cocci - image



shapes of cocci and bacilli - image




What is the most authoritative reference in modern prokaryotic systematics?


Bergey's Manual of Systematic Bacteriology.  It classifies prokaryotes into 3 phyla of Archaea and 3 phyla of bacteria.


At one time the prokaryotes were classified by ______.  More recently, the classification of living things has been based more on _______.


were classified by growth habits.

now it's based more on genetic relatedness - DNA, RNA, and protein sequences.


A many as _____% of prokaryotes have never been isolated or cultured.


99.5%


What are some common features of microbes in the domain Archaea?


  • Archaea lack peptidoglycan in their cell walls.
  • Their cell membrane lipids have branched hydrocarbon chains.
  • It's AUG start codon is similar to eukaryotes and in contrast to bacteria.



How do archaea reproduce?


  1. binary fission
  2. budding
  3. fragmentation.



What diseases do archaea cause?


None.


The most noted archaea are


methanogens, organisms that generate methane gas.

extremophiles, microbes that require extreme conditions of temperature, pH, and/or salinity to survive.


Name two prominent extremophiles and give their features


  1. thermophiles - Must live at temperatures over 45-degrees C.  Hyperthermophiles require temperatures over 80-degrees C.
  2. halophiles - They must live in extremely saline habitats such as the Dead See or the Great Salt Lake.



What is the most studied halophile?


Halobacterium salinarium.  It uses light energy to drive the synthesis of ATP.  It lacks photosyntheticchlorophylls so it synthesizes purple proteins called bacteriorhodopsins that absorb light energy.


Name four significant roles played by methanogens in the environment.


  1. They convert organic wastes in pond, lake, and ocean sediments into methane.
  2. Some live in the colons of animals and are one of the primary sources of environmental methane.
  3. they have useful industrial applications; sewage treatment where they burn methane to heat buildings and generate electricity.
  4. They have produced about 10 trillion tons of methane which is twice the known amount of oil, natural gas, and coal combined.



The classification scheme for bacteria once emphasized _______, _____, and ______ characteristics.  Today classification is largely based upon _______.


The classification scheme for bacteria once emphasized morphology, Gram reaction, and biochemical characteristics.  Today classification is largely based upon genetic relationships among bacteria.


Describe what is meant by deeply branching bacteria.


They are so named because their rRNA and growth characteristics lead scientilsts to believe these bacteria are similar and branched off the "tree of life" at an early stage.  Deeply branching bacteria live in environment that existed on early Earth - hot, acidic, anaerobic, and intense ultraviolet radiation from the sun.


What is phototrophic bacteria?


Bacteria that trap light energy with photosynthetic lamellae.


The five groups of phototrophic bacteria are -


  1. cyanobacteria
  2. greensulfur bacteria
  3. green nonsulfur bacteria
  4. purple sulfur bacteria
  5. purple nonsulfur bacteria



How do phototrophic bacteria differ from plants, algae, and cyanobacteria?


  1. They use bacteriochlorophylls for photosynthesis instead of chlorophyll.
  2. They are anoxygenic - meaning they do not generate oxygen during photosynthesis.



Cyanobacteria


Used to be called blue-green algae - now it's known that it's a prokaryote.

It reduces nitrogen gas to ammonia via a process called nitrogen fixation.



What is nitrogen fixation?


Cyanobacteria reduces nitrogen gas to ammonia via a process called nitrogen fixation.

It is essential for life on Earth because nitrogen-fixers not only are able to enrich their own growth but also provide nitrogen in a usable form to other organisms.


Many cyanobacteria fix nitrogen in thick-walled cells called _____.


heterocysts.


What is Clostridium botulinum known for?


It's a killer and a healer.  Causes botulism but can also help erase wrinkles in botox and help people with eye problems, to reduce muscle contractions.


Explain G+C ratio.


The ratio is the percentage of base pairs in a genome that are guanine-cytosine base pairs. 

If there are fewer than 50% G-C pairs, it's considered LOW.  Above 50% is considered HIGH.


Provide the following -

Firmicutes - Clostridia (Clostridium)
  1. Genera
  2. G+C ratio
  3. Special characteristics
  4. Diseases



  1. Clostridium
  2. LOW
  3. endospore formers
  4. Tetanus, botulism, gangrene, severe diarrhea



Provide the following -

Firmicutes - Clostridia (Epulopiscium)
  1. Genera
  2. G+C ratio
  3. Special characteristics
  4. Diseases



  1. epulopiscium
  2. LOW
  3. Giant rods
  4. none



Provide the following -

Firmicutes - Clostridia (Veillonella)
  1. Genera
  2. G+C ratio
  3. Special characteristics
  4. Diseases



  1. Veillonella
  2. LOW
  3. Part of oral biofilm on human teeth; stain like Gram-negative
  4. dental caries



Provide the following -

Firmicutes - Mollicutes
  1. Genera
  2. G+C ratio
  3. Special characteristics
  4. Diseases



  1. Mycoplasma
  2. LOW
  3. Lack cell walls; pleomorphic, stain like Gram-negative bacteria (red)
  4. Pneumonia, urinary tract infections



Provide the following -

Firmicutes - Clostridia
  1. Genera
  2. G+C ratio
  3. Special characteristics
  4. Diseases
Provide the following -

Firmicutes - Bacilli (Bacillus)
  1. Genera
  2. G+C ratio
  3. Special characteristics
  4. Diseases



  1. Bacillus
  2. LOW
  3. endospore formers
  4. anthrax



Provide the following -

Firmicutes - Bacilli (Listeria)
  1. Genera
  2. G+C ratio
  3. Special characteristics
  4. Diseases



  1. Listeria
  2. LOW
  3. contaminates dairy products
  4. listeriosis



Provide the following -

Firmicutes - Bacilli (lactobacillus)
  1. Genera
  2. G+C ratio
  3. Special characteristics
  4. Diseases



  1. lactobacillus
  2. LOW
  3. Produce yogurt, buttermilk, pickles, sauerkraut
  4. rare blood infections



Provide the following -

Firmicutes - Bacilli (streptococcus)
  1. Genera
  2. G+C ratio
  3. Special characteristics
  4. Diseases



  1. streptococcus
  2. LOW
  3. cocci in chains
  4. strep throat, scarlet fever



Provide the following -

Firmicutes - Bacilli (staphylococcus)
  1. Genera
  2. G+C ratio
  3. Special characteristics
  4. Diseases



  1. staphylococcus
  2. LOW
  3. cocci in clusters
  4. food poisoning, bacteremia



Provide the following -

Actinobacteria (Corynebacterium)
  1. Genera
  2. G+C ratio
  3. Special characteristics
  4. Diseases



  1. Corynebacterium

  2. HIGH
  3. Snapping division; metachromatic granules in cytoplasm
  4. diphtheria



Provide the following -

Actinobacteria - (Mycobacterium)
  1. Genera
  2. G+C ratio
  3. Special characteristics
  4. Diseases



  1. Mycobacterium
  2. HIGH
  3. waxy cell walls
  4. TB and memingitis



Provide the following -

Actinobacteria - (Actinomyces)
  1. Genera
  2. G+C ratio
  3. Special characteristics
  4. Diseases



  1. Actinomyces
  2. HIGH
  3. Filaments
  4. actinomycosis



Provide the following -

Actinobacteria - (Nocardia)
  1. Genera
  2. G+C ratio
  3. Special characteristics
  4. Diseases



  1. Nocardia
  2. HIGH
  3. Filaments; degrade pollutants
  4. lesions



Provide the following -

Actinobacteria - (Streptomyces)
  1. Genera
  2. G+C ratio
  3. Special characteristics
  4. Diseases



  1. Streptomyces
  2. HIGH
  3. Produce antibiotics
  4. rare sinus infections



Class of aerobic Gram-negative bacteria in the phylum proteobacteria capable of growing at very low nutrient levels.


Alphaproteobacteria


Phylum of bacteria that includes clostridia, mycoplasmas, and low G+C Gram-positive bacilli and cocci.


Firmicutes


Phylum of archaea; known only from environmental RNA samples.


Korarchaeota


Long carbon-chain waxy lipid found in walls of cells in genus mycobacterium.  They resist staining with water-based dyes.


mycolic acid


A chain of cocci


Streptococcus


Class of low G+C bacteria which lack cytochromes, enzymes of the Krebs cycle, and cell walls and are pleomorphic.


Mycoplasmas


Group of tiny, Gram-negative, parasites that appear almost wall-less


Rickettsias


A cyanobacteria that reduces nitrogen.


Heterocyst


A stiff spiral-shaped prokaryotic cell.


Spirillus


Inclusions of Corynebacteria that store phosphate and stain differently from the rest of the cytoplasm.


metachromatic granules


The reproductive cell of actinomycetes and fungi


spore


Gram-negative, aerobic, soil-dwelling bacteria with unique life cycle including a stage of differentiation into fruiting bodies containing resistant myxospores.


myxobacteria


Spherical prokaryotic cell


coccus


In cell morphology, a folded arrangement of bacilli.


palisade


Group of Gram-negative rods, vibrios, and spiraled bacteria in teh phylum proteobacteria.


epsilonproteobacteria (ε-proteobacteria)


Group of gammaproteobacteria (γproteo...), which are obligate anaerobes and oxidize hydrogen sulfide to sulfur.


purple sulfur bacteria


Any Gram-negative bacterium that utilizes methane both as a carbon and as an energy source


methane oxidizer


Process by which live offspring are produced in teh body of a mother.


viviparity


Phylum of prokaryotes that includes five classes (designated alpha, beta, gamma, delta, and epsilon) of Gram-negative bacteria sharing common 16S rRNA nucleotide sequences.


proteobacteria


Microbe that requires exterme conditions of temperature, Ph, and/or salinity to survive.


extremophile


Gram-negative photosystem bacteria that vary greatly in shape, size, and method of reproduction.


cyanobacteria


In cell morphology, term used to describe a variably shaped prokaryotic cell.


pleomorphic


A cuboidal packet of cocci


sarcina


Any Gram-negative, aerobic, rod-shaped bacterium in teh class Gammaproteobacteria that catabolizes carbohydrates by the Entner-Doudoroff and pentose phosphate pathways.


pseudomonad


The conversion of atmospheric nitrogen to ammonia.


nitrogen fixation


A slightly curved rod-shaped prokaryotic cell.


vibrio


The process by which bacteria convert reduced nitrogen compounds such as ammonia into nitrate, which is more available to plants.


nitrification


the largest and most diverse class of proteobacteria, including purple sulfur bacteria, methane oxidizers, pseudomonads, and others.


Gammaproteobacteria


Any of the small Gram-negative pathogenic cocci that grow and reproduce within the cells of mammals, birds, and a few invertebrates and that spread as elementary bodies.


chlamydia


Microorganism requiring a saline environment great than 9% NaCL


halophile


protozoa that lack mitochondria, Golgi bodies, chloroplasts, and peroxisomes.


Archaezoa


The infectious stage in the life cycle of chlamydias.


elementary bodies


T/F

A bacillus is a bacterium with a slightly curved rod shape.


F

vibrio


T/F

Initial bodies are stable resting stages that do not metabolize but will germinate when conditions improve.


F

Elementary bodies


T/F

Archaea are classified into phyla based primarily on tRNA sequences.


F

rRNA


A giant bacterium that is large enough to be seen without a microscope is


Epulopiscium


When environmental nutrients are depleted _____ aggregate in mounds to form fruiting bodies.


myxobacterium


Bacillus anthracis is associated with _____________.


anthrax


Veillonella is associated with _____________.


dental plaque


Clostridium perfringens is associated with _____________.


gangrene


Clostridium botulinum is associated with _____________.


botulism poisoning


Bacillus licheniformis is associated with _____________.


bacitracin


Streptococcus is associated with _____________.


impetigo


Streptomyces is associated with _____________.


tetracycline


Corynebacterium is associated with _____________.


diptheria


Gluconobacter is associated with _____________.


vinegar


Bordetella is associated with _____________.


pertussis


zoogloea is associated with _____________.


floc formation


Azotobacter is associated with _____________.


nitrogen fixation


Desulfovibrio is associated with _____________.


iron pipe corrosion


Chlamydia is associated with _____________.


lymphogranuloma venereum


Cytophaga is associated with _____________.


wood damage


The type of reproduction in prokaryotes that results in a palisade arrangement of cells is called


snapping division


The thick-walled reproductive spores produced in teh middle of cyanobacterial filaments are called


akinetes


Stiff, spiral-shaped prokaryotic cells are called


spirilla


Halobacterium salinarium must live in high salt concentrations to maintain what?


Its cell wall.


Photosynthetic bacteria that fix nitrogen are


cyanobacteria


What genus is the most common anaerobic human pathogen?


Bacteroides


Bacteria that convert nitrogen gas into ammonia are


nitrogen fixers.


Three types of bacteria that "glide"





Bacteria that "glide."


  1. Myxococcus begin as gliding vegetative cells that aggregate together, forming a large stalk with a fruiting body.



What bacteria is responsible for the development of oxygen on Earth?


Fossil evidence indicates that the cyanobacteria were responsible for the development of the oxygen atmosphere of the early Earth before the appearance of plants.


Key differences among six bacterial phyla.


  1. Proteobacteria - largest phylum. Gram-negative
  2. Cyanobacteria - oxygen-producing photosynthesizers (green and purple bacteria use non-oxygen producing photosynthesis.  Gram-negative.
  3. Firmicutes - Gram positive
  4. Actinomycetes - Gram positive
  5. Chlamydiae - reproduces inside host cells.  gram negative.
  6. Spirochaetes have coiled morphology and muve using axial filaments.



Which is the largest phylum in the domain Bacteria? Is it A) the Firmicutes or B) the Proteobacteria?


The correct answer is B) the Proteobacteria. The phylum Proteobacterium is the largest phylum in the domain Bacteria and contains gram-negative bacteria.


Which domain does not contain prokaryotic organisms? Is it A) the domain Eukarya or B) domain Archaea?


The correct answer is A) the domain Eukarya. The domain Eukarya contains eukaryotic organisms. Prokaryotes are found in the domains Bacteria and Archaea.


Which phylum is known as the "Low G plus C Bacteria"? Is it A) the Firmicutes or B) the Actinomycetes?


The correct answer is A) the Firmicutes. Members of the phylum Firmicutes are known as the "Low G plus C Bacteria". This phylum includes the genera Clostridium, Streptococcus, and Lactobacillus.


To which domain does the genus Methanobacterium belong? Is it A) the domain Archaea or B) the domain Bacteria?


The correct answer is A) the domain Archaea. The genus Methanobacterium and other methane-producing prokaryotes are members of the domain Archaea.


Which of these phyla contains Streptomyces and Mycobacterium? Is it A) the Firmicutes or B) the Actinomycetes?


The correct answer is B) the Actinomycetes. The phylum Actinomycetes contains the genera Mycobacterium and Streptomyces. This group is also known as the "high G plus C bacteria".


Which class within the Proteobacterium contains the human pathogens Salmonella typhi and Vibrio cholerae? Is it A) the class Gammaproteobacterium or B) the class Betaproteobacterium?


The correct answer is A) the class Gammaproteobacterium. The Gammaproteobacterium is a large class within the phylum Proteobacterium. It includes the genera Salmonella and Vibrio.


Which structure of the Chlamydiae attaches and enters host cells? Is it A) the elementary body or B) the reticulate body?


The correct answer is A) the elementary body. The members of the phylum Chlamydiae form elementary bodies which attach and enter host cells.


What is the term for the nitrogen-fixing bacteria found in the class Alphaproteobacteria? Is it A) the enterics or B) the rhizobia?


The correct answer is B) the rhizobia. The rhizobia is a term for the nitrogen-fixing bacteria, such as Rhizobium and Bradyrhizobium, that are members of the class Alphaproteobacteria.


True or False: The odor of dirt is largely due to products of soil-dwelling Streptomyces bacteria.



The correct answer is True.


True or False: The Archaea are never found on the human body.



True or False: The Archaea are never found on the human body. The correct answer is False.


Which phylum is also known as the "High G plus C Bacteria"? Is it A) the phylum Actinomycetes or B) the phylum Firmicutes?


The correct answer is A) the phylum Actinomycetes.


Which genus is used in the commercial production of antibiotics? Is it A) the genus Lactobacillus or B) the genus Streptomyces?


The correct answer is B) the genus Streptomyces.


What structures are used by the Cyanobacteria for nitrogen fixation?


The correct answer is: heterocysts.


What phylum does Escherichia coli belong to?


The correct answer is: the phylum Proteobacteria.


DOMAIN - bacteria
Phylum- Proteobacteria
Class - alphaproteobacteria

Characteristics


All proteobacteria are Gram-negative.

Contains the rhizobia, a group of bacteria found in the root-nodules of plants. The rhizobia include the genus Rhizobium and the genus Bradyrhizobium. Both groups infect the roots of leguminous plants, such as peas, beans, and clover, forming a symbiotic relationship in which the bacteria carry out nitrogen fixation. Another genus in the Alphaproteobacteria class, the Rickettsia, causes human diseases, such as Rocky Mountain spotted fever.


DOMAIN - bacteria
Phylum- Proteobacteria
Class - betaproteobacteria

Characteristics


Gram-negative

contains the genus Zoogloea. Zoogloea cells acts in sewage treatment by forming fluffy, slimy masses that are essential to the proper functioning of sewage treatment plants. This class also includes Bordetella pertussis, which causes whooping cough, and the genus Neisseria. Neisseria gonorrhea causes gonorrhea, a sexually transmitted disease, and Neisseria meningititis, causes meningitis.


DOMAIN - bacteria
Phylum- Proteobacteria
Class - gammaproteobacteria

Characteristics


Gram-negative.  Largest class or proteobacteria.

includes organisms that are very familiar to you, such as Escherichia coli, and other enteric or intestinal-dwelling bacteria. Several important human pathogens are found in the Gammaprotebacteria, such as Vibrio cholerae, the cause of cholera, and Salmonella typhi, which causes typhoid fever. Another member of this class, the genus Pseudomonas, lives in soil and water, and causes opportunistic infections in humans.


DOMAIN - bacteria
Phylum- Proteobacteria
Class - deltaproteobacteria

Characteristics


Gram negative

Myxococcus
, resembles the eukaryotic slime molds with a complex life cycle. Members of the Myxococcus begin as gliding vegetative cells that aggregate together, forming a large stalk with a fruiting body. The fruiting body then forms spores, which germinate and form new vegetative, gliding cells. These bacteria actually prey on other bacteria by attacking and using them as a food source.


DOMAIN - bacteria
Phylum- Proteobacteria
Class - epsilonproteobacteria

Characteristics


Gram negative.

This class includes the genus Helicobacter. One member, Helicobacter pylori, is the most common cause of peptic ulcers in humans and is a cause of stomach cancer.


DOMAIN - bacteria
Phylum- cyanobacteria

Characteristics


aerobic, photosynthetic, gram-negative bacteria that carry out oxygen-producing photosynthesis, similar to plants. They are blue-green in color, and were once named the "blue-green algae." This is a misnomer, so do not confuse them with the eukaryotic algae! The cyanobacteria are bacteria, not algae. Fossil evidence indicates that the cyanobacteria were responsible for the development of the oxygen atmosphere of the early Earth before the appearance of plants.


DOMAIN - bacteria
Phylum- gram-negative nonproteobacteria
Class - purple and green photosynthetic bacteria

Characteristics


Unlike plants or cyanobacteria, the photosynthesis of the purple and green bacteria is anoxygenic and does not produce oxygen. Instead of oxygen, the purple sulfur and the green sulfur bacteria produce sulfur granules. These bacteria live in the deep sediments of ponds and lakes.


DOMAIN - bacteria
Phylum- gram-positive bacteria
Class - Firmicutes and the Actinobacteria

Characteristics





These two phyla are distinguished from each other by the guanine plus cytosine, or G plus C, content of their DNA. The Firmicutes are also called the "Low G plus C Bacteria" because their G plus C content falls between 20 to 50 percent. The Actinobacteria are also called the "High G plus C Bacteria" because their G plus C content ranges between 50 to 70 percent.


DOMAIN - bacteria
Phylum- gram-positive bacteria
Class - Firmicutes continued

Characteristics





The low G plus C phylum Firmicutes includes the genera Clostridium, Streptococcus, and Lactobacillus. The genus Clostridium contains several important human pathogens, including the causative agents of botulism and tetanus. The genus Streptococcus includes species that cause strep throat and tooth decay. However, not all members of this phylum are harmful to humans. The Lactobacilli are normal flora organisms in the human intestine and reproductive tract. Lactobacillus bacteria are also used in the commercial production of yogurt and buttermilk.


DOMAIN - bacteria
Phylum- gram-positive bacteria
Class - Actinobacteria continued

Characteristics





The Actinobacteria, the high G plus C bacteria, include the genera Mycobacterium and Streptomyces. Several members of genus Mycobacterium cause disease in humans, such as Mycobacterium tuberculosis, which causes tuberculosis, and Mycobacterium leprae, which causes leprosy.


DOMAIN - bacteria
genus - Streptomyces

Characteristics


genus Streptomyces are common in the soil and are the source of most commercial antibiotics. If you have the chance to smell a culture of Streptomyces, you may notice a familiar odor. It smells like dirt! In fact, the musty odor of dirt is due to the production of a compound called geosmin, formed by the Streptomyces which are abundant in soil. So, the next time you smell dirt, think of Streptomyces!


DOMAIN - bacteria
phylum - Chlamydiae

Characteristics


The Chlamydiae are gram-negative and can only grow inside a host cell. Unlike other bacteria, the Chlamydiae do not reproduce by binary fission. Instead, they form an elementary body which attaches and enters a host cell. Inside a host cell vacuole, the elementary body forms a reticulate body. The reticulate body divides many times, forming elementary bodies that are released and invade surrounding host cells. Several members of the Chlamydiae are human pathogens. Chlamydia trachomatis is responsible for several diseases in humans, including nongonococcal urethritis and trachoma. Trachoma is the leading cause of blindness in under-developed countries.


DOMAIN - bacteria
phylum - Spriochaetes

Characteristics


The Spirochaetes have a tightly coiled, spring-like morphology and a unique form of motility that involves axial filaments, or endoflagella, which are embedded within their cell walls. The axial filaments stretch and relax, allowing movement of the cells. The pathogenic members of this phylum include Borrelia burgdorferii , the cause of Lyme disease, and Treponema pallidum, the cause of syphilis.


Bacteria don't reproduce sexually. 

How do you define their their species?


But bacteria don't reproduce sexually.  How do you define?  By molecular chronometer  (how to measure time) and we measure time on a molecular scale.  Has to be present in all species.  If it's not in one of them, we can't put that into our tree. We use ribosomal RNA as the molecular chronometer because all organisms have that.  So humans fall into one category, ducks...everybody has ribosomes so we can group all different orgs this way.


Do viruses have rRNA for classification?


No.

Viruses do not have rRNA, so it's missing from the tree.


What qualifications must be met to be part of the same species?


Anything above 70 genome similarity and anything above 97 ribosomal similarity is a similar species.


Define phototrophy and chemotrophy in bacteria


Phototrophy - bacteria gets energy from the sun.
Chemotrophy - bacteria gets energy from chemicals


deinococcus - special characteristic of this proteobacteria



is resistant to radiation.  So part of one gets damaged another can replace it.


Phototrophic bacteria - cyanobacteria produced



Phototrophic bacteria - cyanobacteria produced all oxygen on earth.


Archaea - common features


Archaea:
common features
  • lack peptidoglycan
  • cell membrane lipids have branched hydrocarbon chains.
  • classified in three fhyla crenarchaeota, euryarchaeota, and korarchaeota (viable but not culturable)
  • reproduce by binary fission, budding, and fragmentation
  • most are cocci, bacilli, or spiral forms,
  • not known to cause disease.



General characteristics of eukaryotic organisms.


General characteristics of eukaryotic orgs
five major groups
  • protozoa
  • fungi
  • algae
  • water molds
  • slime molds



Protozoa - common characteristics


Protozoa
Diverse group defined by three characteristics
  • eukaryotic
  • unicellular
  • lack a cell wall
  • motile by means of cilia, flagella, and/or pseudopodia (except subgroup, apicomplexans)
  • cilia is for locomotion on protozoa



Does bacteria have cilia or fimbraea?


fimbraea is on bacteria to stick to things...bacteria does not have cilia, which is a locomotive for protozoa



Protozoa
distribution of protozoa


Protozoa
distribution of protozoa
  • requires moist environments
  • most live worldwide in ponds, streams, lakes, oceans; critical members of plankton
  • others live in moist soil, beach sand, and organic matter
  • very few pathogens



Protozoa
nutrition of protozoa



Nutrition of protozoa
  • most are chemoheterotrophic
  • obtain nutrients by phagocytiizng bacteria, decaying organic matter, other protozoa or tissues of host
  • few absorb nutrients from surrounding watter
  • dinoflagellates and euglenoids are photoautorophic



Protozoa
reproduction


Reproduction in protozoa
  • most reproduce asexually only (binary fission or schizogony)
  • few also have sexual reproduction



Fungi
Nutrition of fungi


Fungi -
Nutrition of fungi
  • Acquire nutrients by absorption
  • most are saprobes
  • some trap and kill microscopic soil-dwelling nematodes
  • most are aerobic; some are anaerobic; many yeasts are facultative anaerobes



Fungi
reproduction


Reproduction in fungi
  • all have some means of asexual reproduction involving mitosis and cytokinesis
  • most also reproduce sexually



Define lichens and give common characteristics -


Lichens
  • partnerships between fungi and photosynthetic microbes (green algae or cyanobacteria)
  • abundant throughout the world, particularly in pristine habitats
  • grown on soil, rocks, leaves,
  • occur in three basic shapes
  • important in creation of soil from rocks
  • eaten by many animals



Algae does/does not cause disease in humans.  Why or why not?


Do not cause disease in humans.  Why?  Most organisms that cause disease go inside of us.  There isn't any light inside, so that's why algae doesn't survive to hurt us.