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KINGDOM MONERA

The Prokaryotes:

Archaebacteria and Eubacteria

• Bacteria are the most _________organisms living on the Earth. (i.e. 10mL of soil contains 1 x 1010 bacteria.

• They are found in nearly every habitat studied, including habitats that no other ___________ are able to withstand.

• Bacteria all share these five characteristics-All bacteria are _______-celled-All bacteria are ___________. Their DNA is not surrounded by a membrane.-Cell __________ in bacteria are not surrounded by membranes.-The DNA of bacteria is made of a single ____________.-All bacteria reproduce asexually by _______ fission.

• Bacteria are the smallest organisms measuring from _____ micrometres.

• It contains a _______that provides support and protection for the contents of the cell. Some are also covered by a _____ capsule.

• The cytoplasm contains _________, responsible for the formation of proteins and DNA.

• The DNA forms a single chromosome and forms a _____ rather than a strand.

• Some bacteria have a whip-like ________ that act like propellers moving the organism forward.

• Bacteria are ________ by their shape, reaction to being stained, nutrition and respiration.

Bacterial Cell Shape• Bacteria can be classified by shape.-A spherical cell is called a _______ (pl. cocci)-A rod-shaped cell is called a _________ (pl. bacilli)-A spiral-shaped cell is called a _________ (pl. spirilla)

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Staining bacteria results in two forms: gram-________ (purple) vs. gram ________(pink).

Gram positive:accepts crystal violet stain.

Gram negative: Peptidoglycan layer is covered.

Nutrition• Nutrition means obtaining _______ and a source of ______

to produce the organic compounds needed for cellular metabolism.

• Most bacteria are __________ and obtain energy by breaking down organic molecules from their environment. Some are _________, absorbing nutrients from living organisms. Others are ___________, decomposing dead organic matter.

• Some bacteria are autotrophs and produce their own ________ compounds. (example- cyanobacteria (blue-green bacteria) are photoautotrophs using ______ for energy, but they lack true chloroplasts.

Mode of nutritionMode of nutrition Energy SourceEnergy Source Carbon SourceCarbon SourcePhotoautotrophPhotoautotroph Light Light Carbon DioxideCarbon DioxideChemoautotrophChemoautotroph Inorganic Chemicals Inorganic Chemicals Carbon DioxideCarbon DioxidePhotoheterotrophPhotoheterotroph LightLight Organic CompoundsOrganic CompoundsChemoheterotrophChemoheterotroph Organic Compounds Organic Compounds Organic CompoundsOrganic Compounds

Nutrition• Most are ___________ although some are

autotrophs.

• The autotrophic bacteria either use ________ as a source of energy (chemoautotrophs) or are _____________ (photoautotrophs).

• Some are parasites which live off a living _____

Leucothrix mucor

• Some are _______, feeding off dead organisms and ______ (i.e., decomposers).

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Respiration• Chemical reactions take place on the _____ ______of the cell

membrane so that gases can pass into and out of cells easily.• All living things must carry out cellular __________ to receive

energy. Bacteria differ in whether or not they require oxygen.• If respiration requires oxygen, bacteria are termed _______. If

oxygen is absolutely necessary for survival they are called ________ aerobes.

• Bacteria that carry out respiration without oxygen are called_________. Presence of oxygen kills some bacteria and these are called obligate ___________. (example- Clostridium botulinum produces toxins that can cause an extreme form of food poisoning called botulism.)

• Another group of bacteria can survive with or without oxygen and they are called __________ anaerobes.

Reproduction• Bacteria reproduce

asexually and divide by the process of _______ ______.

• In binary fission, the parent cell divides into two offspring cells that are completely ________.

• There is no exchange of genetic material so the process is _______.

• E. coli produces between _____ ________bacteria in 12 hrs

Asexual - Binary Fission• _________ reproduce by simply splitting in

two

• The DNA is copied and the ____ divides into two identical cells.

• When conditions begin to ____, either through decrease of food or space, or cooler temperatures, some bacteria take part in a type of sexual reproduction called __________.

• In conjugation the two cells join briefly and one cell donates some _____ (called plasmid) to the other one.

• Sexual reproduction _________ genetic information from two different individuals and increases variation.

Sexual - Conjugation• Sexual reproduction combines ______ from two

different individuals and increases variation. __________ do not technically reproduce sexually but can mix genes with one another.

• Transformation - Bacteria can also pick up pieces of DNA from the __________

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• Transduction - sometimes ________ transfer pieces of DNA from one cell to another.

• ________ is a large source of genetic diversity in bacteria.

Under ultraviolet light in a Petri dish containing laundry whitener, symbiotic bacteria with a mutant bluB gene (lower right) fluoresce brightly, while the same bacteria with no mutation only glow slightly (top right), and bacteria with another mutation (in the exoY gene) are completely dark.

• When growth conditions become extremely unfavorable, many ____ _______ bacteria form structures called endospores.

• Endospores are DNA and a small amount of ________ enclosed in a tough cell wall.

• They are ________ to extremes in temperature, drying, and harsh chemicals.

Kingdom Monera ClassificationThe Phyla

_________Gram negative

________Gram positive

_________No cell wall

____________Exotic cell wallArcheabacteria

Gracilicutes

_____bacteriaNon-photosynthetic _________bacteria

non-oxygen producing

________bacteriaoxygen producing

Most pathogenici.e. Lyme DiseaseSalmonellaOthers: E.coli in gut

Live in sediments and lakes.Release sulpher

Cyanobacteria(blue-green algae)

Firmicutes

_____bacteria(rod or cocci)

_______bacteria(other shapes)

C. BotulinumS. pneumoniae

Dental/gumdiseases

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Tenericutes

__________

Other strains of pneumonia

Halophiles-“___-______” found in salt lakes such as the Dead Sea.

Mendosicutes

_______bacteria (ancient)

Anaerobic Methanogens- live in the gut of animals, swamps and marshes. Produce all the methane ___found in the Earth’s atmosphere.

Thermophiles –_______ hot, acidic environments such as hot springs.

The pros and cons of Bacteria• Bacteria ________ atmospheric nitrogen into a useable form

of nitrogen. (nitrogen-fixers)• Bacteria play an important role in recycling by ________ down

dead and decaying organic matter. Used to eliminate or ________ toxic and hazardous waste and spills. Also used in sewage treatment to decompose the 5 ______ kg of solid waste produced daily.

• Bacteria is used to produce ______ foods that help maintain a healthy balance of microorganisms in the digestive system.

• Only a small percentage of prokaryotes are ________, or disease causing. These bacteria produce deadly toxins in the human body that cause disease symptoms. ___________ are seldom fatal and cause fever, vomiting and diarrhea. E. coli, Salmonella. __________ are highly toxic, do not cause a fever and are often fatal. Tetanus and botulism.Example- Toxins released by the bacterium Streptococcus pneumoniae may result in symptoms of pneumonia.

Review Questions1. Why are bacteria classified in their own kingdom and not with plants, animals,

protists, or fungi?2. What features are shared by prokaryotes?3. What feature(s) might cause cyanobacteria to be classified as plants by some

taxonomists?4. Describe three shapes that bacteria can have.5. Why is endospore formation important to bacteria?6. What method of reproduction is used in bacteria? 7. What is conjugation in monerans? Why is it important?8. How is conjugation different from transformation? 9. A protective slime coat around some species of bacterium known as a ____

makes them more capable of causing disease.10. Why are monerans considered more primitive than protists?11. What is the difference between a saprobe and a parasite? 12. How do obligate aerobes differ from facultative aerobes? 13. _____ are organisms that die in the presence of oxygen.14. Monerans belong to a group of organisms known as prokaryotes. Discuss the

differences between eukaryotes and prokaryotes in terms of cell wall, nuclear membrane, and chromosomes.

15. Why does dried or salted food resist spoiling by bacteria?

16. Give specific examples showing the importance of microbial sterility in

a) your kitchenb) a microbiology lab

17. Describe the results if all bacteria died.

18. Endosporesa) are produced by viruses b) are reproductive structures

c) are very delicate and can easily be killed d) are resting structures

19. An obligate anaerobe woulda) grow equally well with or without free oxygen

b) grow well with free oxygen but better without it

c) die without oxygend) grow only in the absence of free oxygen

20. Why are archaebacteria considered the oldest organisms on Earth?