Quiz#1-Bacteria and Archaea Flashcards
rRNA
This is the type of RNA that is contained in ribosomes(molecular factory
Ribosomes
complexes of RNA found in both prokaryotes and Eukaryotes. Their function is to synthesize proteins by nucleic acids are coded and linked to Amino Acids to make proteins.
Organelles
Membrane compartments in eukaryotes, that are specialized in a specific function, defined by the reactions they can carry out.
Nucleoid
Region in a prokayotic cell that contains the DNA
Peptidoglycan
A polymer of amino acids sugars crosslinked to peptides, it serves as a layer around the cell and is enclosed by and outer membrane.
flagella
long, whip-like attachment of a prokaryote that propells the cell allowing it to swim
Domain
a subjective term used for the largest groups of life
Pilus
hailrlike structures attached to the surface of some bacteria, serving to stick to other bacteria and exchange genetic material.
rRNA has been incredibly important for phylogenetic analysis of microbes(for that matter all life). Why?
B/C phylogeny is based on the differences in the sequences of nucleotides in the cells rRNA, the comparison using rRNA is also useful b/c qll rRNA molecules have the same function and they have a structure that changes very little overtime, therefore comparison becomes easy and helpful in phylogeny.
What are biofilms and their importance
biofilms are microbial communities that uses matrices of polycharides to trap other cells and make layers. the importance is that this will make it more difficult to treat pathogenic bacteria since this layer may be impermeable and will resist the antibiotics.
What are the differences btw a prokaryote and a eukaryote?
in prokaryotes the difference is that there is no nucleus nor compartments of organelles that specialize in diff functions,,,,also the cells are much smaller than eukaryotes, and reproduce through binary fission rather then meiosis or mitosis(eukaryotes)…
what is the difference btw aerobic and anaerobic?
anaerobic conditions is in the absence of oxygen while aerobic is requiring oxygen to proceed with metabolic processes.
Binary fission
the reproduction of prokaryotic cells in which the cell divides into two comparable(similar)
gram stain
a staining test that separates or distinguishes between gram positive(when stained appear blue to purple) and gram negative(turns from pink to red)
transformation
gene transfer from the environment to a bacteria
lateral gene transfer(can lead to discordant gene trees
transfer of genes(plasmids)from one species to another, moving sideways,,it may even be among extremely distantly related forms….through this genevtranfer of plasmids bacteria is able to exchange resistance to antibiotics…this is why mire attention is given to prescribing antibiotics….itd debateable whether it may complicate phylogeny analysis since now you can reference entire genomes uncomplicated by LGT
plasmid
small molecules of replicating, circular, extra-chromosomal DNA found in bacteria. It is able to transfer genetically
asexual reproduction
reproduction without mating
chemoheterotroph
(all three domains)obtains carbon and energy from organic compounds
chemolithotroph
some bacteria and archaea)obtains carbon via CO2 and energy from oxidizing inorganic compounds…also called chemoautotroph
anaerobe
in the absence of oxygen b/c it may be poisonous as it was in the beginning of prokaryotic life.an anaerobe therefore does not use oxygen as an electron acceptor in metabolic process like cellular respiration(energy formation process)
aerobe
in the presence of oxygen or requiring oxygen to undergo cellular respiration and therefore to survive.
what are the characteristics of prokaryotic cell walls?
(made up of the peptidoglycan and outer membrane)…..most prokaryotes have a cell wall outside the cell plasma membrane, and the rigidity of the cell wall supports the structure and determines its shape. Most bacteria contain peptidoglycan whcih forms a single giant molecule around the entire cell, which is then enclosed by an outermembrane in some bacteria. Some also contain a capsule surrounding the cell wall
biofilm
microorganisms embedded in a polysaccharide matrix forming a resistant coating on moist surfaces
bacteria
are prokaryotic cells that have same structure components of eukaryotes. Contain cell walls with peptidoglycan, both Gram-positive and gram-negative…can be shaped like a rod spherical and helical forms
eukarya
the domain of life containing unbranched fatty acid with glycerol and an ester linkage. Not all of them contain a cell wall but those that do have one dont have peptidoglycan. Also have unique rRNA.kingdoms of protists, plants, fungi, and animals.
archaea
is one of the three domains of life, they are prokaryotes that have membrane made of branched hydrocarbon chains,with glycerol and an ether linkage, The archaea contain no peptidoglycan and have unique rRNA than the other tow domains. They live in extreme environments(halophile–salty, hyperthermophiles, and methanogens) thanks to their ether linkage,