Viruses - answer-Are derived from the cells of living organisms and infect all cellular
forms of life
-evolve independently of other organisms
-not considered living organisms
-cannot replicate on their own (are parasitic)
-caused by prion
Virus Facts - answer-Protein coat
-DNA or RNA
-Circular or linear genetic material
-single or double stranded
-not cells (virons)
Factors that make viral phylogeny difficult to resolve - answer-tiny size
-rapid mutation rate
-there are no known fossil viruses
-viruses are highly diverse
Prokaryotic
Characteristics - answer-unicellular
-binary fission
-un-enclosed DNA, circular chromosome
-no organelles
-asexual
-Single stranded
-flagella: simple single fiber
-small
-asexual
i. Cell wall: Ubiquitous (peptidoglycan or psuedomurein)
-differ in Bacteria: gram positive vs. gram negative
Eukaryotic
Characteristics - answer-multicellular
-Compartmentalized
-Sexual
-Chromosomes: Double membrane bound nucleus with multiple linear chromosomes
-mitosis and meiosis
-Recombination
-Complex Flagella
-No peptidoglycan
-typically larger
,Horizontal Gene Transfer - answermovement of genetic material between distantly
related organisms
Vertical gene transfer - answermovement of genetic material between related
organisms
Endosymbiotic Theory - answertheory that eukaryote organelles originated through
symbiosis between multiple micro-organisms.
Negative-Sense RNA - answerRNA that is the complement of the mRNA needed for
protein translation. EX: viruses that cause measles, mumps, rabies, and influenza.
Positive sense RNA - answeralready set for translation; no replication of the genome to
form a complement strand is needed before protein translation can take place. Most
abundant and diverse viruses. EX: polio, hepatitis C, and the common cold.
RNA Retroviruses - answerregenerate themselves by reverse transcription; when it
enters the nucleus of the host, viral reverse transcriptase produces complementary
DNA (cDNA) from the viral RNA genome then replicates that single stranded cDNA to
produce double-stranded DNA. Only known to infect vertebrates. EX: HIV
Proviruses - answerintegrated retroviral DNA
Double Stranded RNA Viruses - answerevolved repeatedly from single stranded RNA
ancestors or perhaps vice versa. Infect through the tree of life.
Prokaryotes - answer2/3's of the domains of the tree of life
-oldest and simplest life forms
Aerobes - answerNeed oxygen
Anaerobes - answerpoisoned by oxygen
Autotrophs - answerSelf feeders
Heterotrophs - answerother feeders that feed off of other organisms; obtain both energy
and carbon from other organisms: decomposers and the pathogens
Photoautotrophs - answercritical to the change of atmosphere on earth
Chemoautotrophs - answerbreak the bonds and capture the energy stored in these
chemicals found at the sea floor near hot vents
Heat lovers - answerHyperthermophilic bacteria and hadobacteria
, Cyanobacteria - answer-Critical photoautotrophs
-Blue and green bacteria
-Carry out the same photosynthesis are eukaryotes
-Plants are derived from cyanobacteria
-Gram negative
-release oxygen into the atmosphere. May live free as single cells or associate in
multicellular colonies.
Spirochetes - answer-have axial filaments and are common pathogens
-muti-heterotrophs
-Rotate inside the spiral
Chlamydia's - answer-very small, parasitic and cocci
-small
-gram negative
-cannot live independently
-known as a STD
Proteobacteria - answer-Have very diverse metabolic pathways
-most diverse
-know as purple bacteria
-variability of metabolism
Gram Positive Bacteria - answerhave a uniformly dense cell wall consisting primarily of
peptidoglycan.
Gram Negative Bacteria - answerhave a very thin peptidoglycan layer and an outer
membrane
Peptidoglycan - answercross-linked polymer of amino sugars that produces a firm,
protective, mesh like structure around the cell
Gram Stain - answertechnique used to separate most types of bacteria into 2 distinct
groups
events that led to the origin of the eukaryotic cell - answer-Flexible cell surface
-Cytoskeleton
-Nuclear envelope
-Digestive Vacuoles
-Endosymbiosis
loss of cell wall - answer-Allowed / Increased a larger surface area
-Allowing new structures to be created
-critical to development of eukaryotic cell
Endosymbiosis - answerDefined as living together in a close formation over time