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21 Cards in this Set
- Front
- Back
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What were the first organisms to live on Earth?
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forms of simple, single-celled organisms
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archaebacteria
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the oldest known living things and are often grouped in their own eponymous kinddom
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methanogens
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an ancient organism that synthesize methane from carbon dioxide and hydrogen gases
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thermoacidophiles and halobacteria
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ancient organisms
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The ancient organisms proto-prokaryote differ from general prokaryote how?
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-They did not use the Calvin cycle to reduce carbon.
-They contained their own unique coenzymes to stand in for and perform the functions of NAD and FAD. -They contained very different nucleotide sequences in their ribosomal and transfer RNA. |
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archaebacteria gave rise to?
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single-celled prokarotes
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What Kingdom are prokaryotes?
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Kingdom Monera
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Characteristics of single celled prokaryotes?
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-lack of membrane-bound nucleus
-lack of membrane-bound organelles (the strand of DNA floats freely in the cytoplasm) -a phospholipid and cholesterol cell membrane -a complex, polymer (peptidoglycan) cell wall that gives the cell shape, but which may be rigid or flexible -flagella (singular, flagellum) or pili (singular, pilus), attached to the cell wall, are often present; pili and flagella are beaten rapidly to aid locomotion -reproduction is asexual and commonly by binary fission |
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What are the 4 characteristic shapes of prokaryotes?
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-rod-shaped bacteria , also called bacilli (e.g., E. coli)
-spherical bacteria , also called cocci (e.g. Diplococcus pneumoniae) -spiral-shaped bacteria , also called spirilla -incomplete spirals called vibrios |
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What are the two bacteria that have a unique shape?
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spirochetes (e.g., Terponema pallidum, which causes syphilis), which can be incredibly long, and rickettsiae (e.g., Rickettsia prowazeki, which causes typhus), which are the smallest cells known.
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How is most prokaryote locomotion accomplished?
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rapid beating of the pili
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By what means is prokaryote reproduction?
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binary fission (cell division)
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budding
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a genetically identical offspring develops out of the parent's body and eventually buds off from the parents
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most prokaryotes are?
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heterotrophs consuming dead organic matter
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chemotrophs
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use inorganic materials as a source of energy like archaebacteria
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eubacteria
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sulfur photosynthetic bacteria
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cyanophytes
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nonsulfur photosynthetic bacteria
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Which of the following is a characteristic of Archaebacteria?
A They have at least one flagellum. B They thrive in highly saline environments. C They contain no NAD or FAD. D They synthesize hydrocarbons. |
The correct answer is C. Archaebacteria have unique electron transfer coenzymes that take the place of NAD and FAD. The presence or absence of flagella is not characteristic of this classification of organisms, so A is not correct. Only one type of archaebacteria, the halobacteria, thrives in saline conditions, so B is incorrect. Similarly, only methanogens synthesize hydrocarbons (methane), so D is not correct.
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The most common form of reproduction among prokaryotes is
A fragmentation. B binary fission. C budding. D sporulation. |
The correct answer is B. Most prokaryotes reproduce asexually via cell division, or binary fission. Fragmentation is the regeneration of a lost part of the organism, as in starfish, so A is not correct. Some prokaryotes do reproduce via budding, but it is not common, so C is incorrect. Similarly, some prokaryotes produce spores, but this is fairly rare among prokaryotes, so D is not correct.
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Most prokaryotes are heterotrophs that ingest
A autotrophs. B other hetertrophic bacteria. C inorganic matter. D decaying organic matter. |
The correct answer is D. Most prokaryotes live in soil, where they ingest and decompose decaying organic matter and release it into the soil. Some heterotrophic prokaryotes may consume unicellular autotrophs, but this is not widespread, so A is incorrect. Similarly, some heterotrophic prokaryotes may ingest others of their kind, but this is not common, so B is incorrect. Chemotrophs do metabolize inorganic substances, but they are a small sector of the prokaryotic community, so C is not correct.
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Which of the following are eubacteria?
A Rickettsiae B Vibrios C Mycoplasmas D Cyanophytes |
The correct answer is D. Cyanophytes are photosynthetic (like all eubacteria) marine eubacteria that put the oxygen into our atmosphere. Rickettsiae are pathogenic, nonphotosynthetic prokaryotes, so A is not correct. Vibrios are a category of prokaryotes based on their incomplete spiral shape. They are not photosynthetic and so are not eubacteria; thus, B is incorrect. Mycoplasmas are heterotrophic, not autotrophic, prokaryotes, so C is not correct
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