Chapter 23 Flashcards
What are the two major domains in prokaryotes?
Archaea and bacteria
NOTES
they are both singled cell organisms that do not have a membrane bound organelle,they are source of food for many organisms,they also act as decomposers which helps the environment.
Archaea and bacteria both live in extreme environments but which one lives mostly in extreme environments
Archaea
What does the word Archaea mean?
Ancient
What is rRNA and what is it used for?
All life have rRNA and can be used to make comparisons between different organisms species.
What are the benefits of rRNA changing very slowly overtime?
we can use it to track relationships, evolutionary linkages and common ancestors.
Which two share a more common ancestor Bacteria & eukarya or archaea & eukarya?
Archaea & Eukarya
Why are archaea and eukaryotes share more common ancestry than bacteria and eukaryotes?
Even though Archaea belongs to the same domain as bacteria, their genes resemble Eukaryotes more.
What separates archaea from bacteria
Archaea does not have a peptidoglycan.
And their genetics they have introns (portions of DNA transcribed into RNA) like eukaryotes.
Name some archaeal groups
Methanogens
Halophiles
Thermoacidophiles
What are Methanogens?
An archaea that obtains energy from converting hydrogen gas and carbon dioxide into methane gas.
Where methanogens live?
In anaerobic conditions such as cow’s intestines and deep waters, sewers and swamps.
Define anaerobic.
Oxygen is absent.
What are halophiles?
Salt loving archaea.
Where do halophiles live?
In areas with high concentrated salt such as the Dead Sea.
What are thermoacidophiles?
Heat and acid loving archaea.
Where do Thermoacidophiles live?
In very acidic and high temperature environments.
Such as near volcanoes and black smokers.
What are black smokers?
Hydrothermal vents ( cracks in the ocean floor that leak very hot dark colored water.
Name the three shapes most Bacteria come in.
Bacilli (rod shaped)
Cocci (spherical shaped)
Spirilla (spiral shaped)
What are streptococci?
When cocci occur in chains.
What are staphylococci?
When cocci occur in clusters.
What is gram stain?
Grouping bacteria into two groups based on the structure of their cell wall.
What are the two groups in gram stain?
Gram positive bacteria and gram negative bacteria.
What is the difference between gram positive and gram negative?
Gram positive has a thick peptidoglycan gram negative has a thin peptidoglycan and gram negative has an outer membrane containing lipopollysacharides surrounding the cell.
How do prokaryotes use transformation?
Prokaryotes pick up genes from DNA in the environment by transformation.
Name four gram negative bacterias
Proteobacteria
Cyanobacteria
Chlamydia
Spirochete
What is a proteobacteria?
A nitrogen fixing bacteria which is also gram negative.
What is a disease caused by proteobacteria?
Agrobacterium which causes tumors in plants.
What is a Cyanobacteria?
A gram negative bacteria that uses photosynthesis to get energy from the sun which means they produce oxygen.
What is believed to be the first oxygen producing organism and a contributor to adding oxygen when the atmosphere was thin.
Cyanobacteria
_____ offer a large amount of food for marine life.
Cyanobacteria
Give an example of Proteobacteria.
E. coli.
Give an example of Cyanobacteria.
Anabaena.
What are spirochetes?
Spiral shaped gram negative bacteria.
Comes in both aerobic and anaerobic.
How do spirochetes move?
In a corkscrew-like motion.
There is a strain of spirochetes that causes the _____ disease
Lyme
Give an example of spirochetes
Syphilis
What is a chlamydia?
A bacteria with no peptidoglycan, they live in animal cells for protection and nutrients.
It is also an STI.
Give examples of gram positive bacteria.
Actinomycetes
Botulinum
What is the importance of cell wall in Bacteria and archaea?
It provides shape and protection and can also add to their disease causing abilities (bacteria)
What are archaeal cells made of?
Psuedomurein
What are obligate anaerobes?
Prokaryotes that Cannot live where O2 is present.
Give an example of obligate anaerobes.
Tetani which causes tetanus (nerve damage)
What are facultative anaerobes?
Prokaryotes that can live with or without CO2.
Give an example of facultative anaerobes.
E. Coli which infects the gut.
What are I obligate aerobes?
Prokaryotes that cannot live without O2.
Give an example of obligate aerobes.
M. Tuberculosis which causes lung disease. (TB)
An important finding that has improved genetic research is the use of _____ found in thermophiles.
Taq polymerase.
Where are Taq polymerase found?
In thermophiles.
Prokaryotes usually reproduce by ____.
Binary fission.
Name the three methods of prokaryotic recombination.
1) Transformation
2) Conjugation
3) Transduction
What is transformation?
Taking DNA from outside environment.
What is conjugation?
Two prokaryotes binding together, and one transfer DNA by a structure called a sex pilus.
What is transduction.
A virus takes a copy of prokaryotic DNA within it and when it leads it can transfer that DNA.
What is the scientific study of disease called?
Pathology.
What are exotoxins?
Toxic substances that bacteria secrete into their environment.
What are Endotoxins?
Toxic substances (made of lipids and carbohydrates associated with the outer membrane of gram negative bacteria) only released when they die.
What is penicillin?
An antibiotic that blocks the ability to build new cell wall material.
What is Tetracycline?
An antibiotic that blocks protein synthesis.
How are antibiotics made?
By fungi and bacteria.
Why do antibiotics work?
They kill their own kind to prevent competition for recourses.
What are antibiotics that kill more than one type of organism called?
Broad-spectrum antibiotics.
How can antibiotic resistance happen?
-Over prescription of antibiotics.
-Patients not finishing the entire antibiotic course.
What are heat loving bacteria called?
Thermophiles.
What is bioremediation.
A process in which bacteria is used in recycling.
