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Biology Chapter 27

These Are Study Flashcards For My First Bio II Exam 
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Side ASide B
What were the first organisms to inhabit Earth?
Prokaryotes
What are teh three most common shapes of Prokaryotes?
Spherical (Cocci)Rod-shaped (Bacilli)Spiral
What does the cell wall do in Prokaryotes?
Maintains cell shapeProvides physical protectionPrevents bursting in hypotonic environmentPrevents...
If the  Prokaryote loses water, what will happen internally?
Severe water loss inhibits cell reproduction
Eukaryotic cell walls are made of cellulose or chitin, while Prokaryotic cell walls are made...
Peptidoglycan - a network of modified-sugar polymers cross-linked by short polypeptides
Does the Prokaryote have any of these: nuclear envelope, memebrane-bound organelles, introns,...
No to all except circular chromosomes
Do Archaea have peptidoglycan?
No, but they have a lot of other polysaccharides and proteins, NO PEPTIDOGLYCAN
How do we distinguish between different types of (Eu)bacteria? (just the name)
We use the Gram Stain method, divides bacteria into two groups based on cell-wall composition
What is Gram-Positive and Gram-Negative Bacteria?
G-P: simpler walls, large amounts of peptidoglycan on top with cell membrane on bottom and...
How does the Gram-Stain Method Work?
Samples are stained with a crystal violet dye, iodine, alcohol, and then another red dye. GP...
How is Gram-Staining important (like in medicine)
The lipid portions of the lipopolysaccharides of GN bacteria are really toxic, causes fever...
What is the outer most layer of a prokaryote? Cell Wall? (name and define)
The capsule - a sticky later of polysaccharide or protein, enables prokaryote to adhere to...
How exactly do Prokaryotes stick to their substrate or to whatever? (name and define)
Fimbriae - hair-like protein appendages
What are sex pili?
Appendages that pull two cells together priod to DNA transfer from one cell to another
How fast can prokaryotes move?
50 um/sec, 50 times their body length
What is a flagella?
A filament made of flagellin that is connected to a hook and ten a basal apparatus (with a...
How are prok flagella different from euk flagella?
1. Prok flagella are 1/10 the width of euk flagella2. Prok flagella are not covered by an extension...
Explain taxis and how it relates to motility
In a heterogeneous environment, prokaryotes exhibit taxis, movement towards a stimulusChemotaxis...
Some prokaryotic cells do have specialized membranes that perform metabolic functions? What...
The infoldings of the plasma membrane - reminiscent of cristae of mitochondria, function in...
Where are the chromosomes located in the prokaryote?
In a region called the nucleoid
How are the chromosomes arranged?
Prokaryotes usually have ONE single chromosome, just folded, and a couple of small plasmids...
Describe binary fission.
It is quick, in a favorable env.A single prok cell divides into 2Prok can divide every 1-3...
So why don't they take over the world in numbers...
Their reproduction is limited, cell eventually exhausts the nutrient supply, poison themselves...
How do some prokaryotes withstand harsh conditions (hint: resistant cells)
Certain bacteria develop endospores - resistant cellsWhen an essential nutrient is lacking,...
How are prokaryotes so different if they reproduce by binary fission?
Insertions, deletions, base-pair substitutions, other spontaneous mutations, and a LOT of rapid...
What is transformation? 
The genotype and possibly phenotype of a prokaryotic cell are altered by the uptake of foreign...
What is transduction?
First a bacteriophage infects a bacterial cell, the host DNA of the bacteria is fragmented...
What is conjugation?
When genetic material is transferred between two bacterial cells, temporarily joined, through...
What is the F factor?
In most cases, the ability to form the sex pili and donate DNA during conjug results from  whether...
What does F+ F- Hfr mean?
If you have the F plasmid (considering its in a plasmid), that cell is designated F+, functions...
What is the R plasmid?
Some bacteria have resistance genes that code for enzymes that specifically destroy or hinder...
What are photoautotrophs? chemoautotrophs? photoheterotrophs? chemoheterotrophs? What do they...

See picture
Explain obligate an/aerobes and facultative anaerobes?
Ob An - poisoned by O2, live by fermentation or by anaerobic respiration (substances other...
Explain Nitrogen metabolism in some prokaryotes?
Nitrogen is essential for the production of amino acids and nuc acids in all organisms1. Some...
Talk about metabolic cooperation (heterocytes, biofilms)
Cooperation b/w prok allows them to use env resources with other cells. Ex: in Anabaena - photosynth...
Compare Bacteria vs Archaea vs Eukarya in the following:1. Has Nuc Envelope?2. Has Memb bound...

See picture
What are methanogens?
They live in swamps and marshes to produce methane as a waste productThey are strict anaerobes,...
 Describe different symbiotic relationships
Host vs Symbiont (smaller one)1. Mutualism - both symb organisms benefit2. Commensalism - one...
What are exotoxins and endotoxins
Pathogenic prokaryotes cause diseases by releasing these:Exotoxins - cause diseases even if...


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