exam 1 Flashcards
sister groups
Sister taxa are any taxa derived from a common ancestral node.
outgroup taxon
a taxon outside the group of interest alll members of the group are more costly related to each other than they are to the out group
synapomorphy
shared derrived trait
apomorphy
derived trait
monophyletic clade
includes ancestor and all descendents
paraphyletic clade
includes ancestors and some but not all descendents
what is the basic unit of life?
a cell with
- Dna genetic code ordered structures regulation of internal conditions
- growth and developent energy use respodus to stimuli
- repoduce ance evolve
archaea are more closely related to eukarya becasue ?
share genes and metabolic pathways
enzymes used for dna translation and transcription
carl woese
using rna he found that rRNA of archaea and ukarya are more similar to eachother
true or false
prokaryotes are a monopheletic clade
false they are parapheletic
prokaryotic
lack nuclear membrane
how many difernt prokaryotes are in your stomach lining
128 species in your stomach lining
how many difernt prokaryotes are in your small intestine
400
how many difernt prokaryotes are in your large intistine
1000
how many difernt prokaryotes are in you mouth
700
Bacteria and Archaea differ in
- structure
- physiology
- biochemistry
bioremediation
some bacteria and archaea are used to clean pollution
METAGENOMICS
Metagenomics, or environmental sequencing, is a new technique for
documenting the presence of these organisms
It allows researchers to identify species and biochemical pathways by comparing DNA sequences with those of known genes
‘Prokaryote’: basic biology
- cell wall covered by a sticky capsule
- bacteria: peptidoglycan in cell wall
- archaea: unique phospholipid in plasma membrane
peptidoglycan
- single polymer that forms a net-like mesh around the cell.
- Antibiotics interfere with it’s synthesis
Proteobacteria
- origin of mitochondrial DNA
- Proteobacteria taxa to know:
- Escherichia coli (Proteobacteria) -
- Salmonella (Proteobacteria)
- Vibrio (Proteobacteria)
- H. pylori (Proteobacteria)
stomach ulcers caused by what bacteria?
heliocobacter pylori
Vibrio
is a pathogenic bacteria - causes an
infection, typically when people who consume undercooked seafood or swim in contaminated ocean with open wound
also involved in a symbiotic relationship with some fish - Vibrio attaches to food particles in fish guts, is expelled >> bioluminescent, and attracts more to the colony
cyanobacteria
are a form of photosynthetic bacterium common in both marine and freshwater environments deeply pigmented often responsible for blooms in polluted waters both colonial and solitary forms are common some filamentous forms habe cells specialized for ntrogen fixation
- pond scum is really several species of cyanobacteria
- can be very toxic to humans
- oxygen revolution
The Oxygen revolution
aka ‘blue green bacteria’, formally known as ‘blue green algae’
- Oxygen on Earth !!
- No free molecular oxygen for the first 2.3 billion years of Earth’s history
- PHOTOSYTNThETIC! cyanobacteria perform oxygen-producing photosynthesis
- switch from anaerobic respiration to aerobic respiration for Earths organisms
- changed Earth’s atmosphere - to a high oxygen concentration
- Can convert Nitrogen in the atmosphere into an organic form (ammonia or nitrate)
- nucleic acids (DNA)
- proteins
- Many eukaryotes use the ammonia form of nitrogen
Spirochetes
- long coiled shaped cells that stain gram negative
- common in acuatic environments
- -axial filaments
(modified flagella) used in corkscrew-like motion of spirochetes - some spirochetes such as treponema pallidum (sypilis) and borrelia burdorferi (lyme disease) are significant human pathogens
- T ppallidium : causes syphilis
- Borrelia: causes lyme deases
T. pallidium
Sporochete that causes syphalis
Borrelia
Spirochete that causes lyme disease
gram-positive bacteria
B. anthracis (anthrax)
Staphylococcus aureus
- pimples
- toxic shock syndrom
- pneumonia
- meningitis
- sepsis
thermophiles
persist in harsh environments.. possible that this is how early prokaryotes survived and evolved on Earth
ARCHAEA
Eukaryote?
True nucleus
- Endosymbiosis and the origin of Eukaryotes
- 6 Major Eukaryotic lineages
- many are multicellular
what are the 6 major eukarya linages
chromalveolata
rhizaria
archaeaplatida
excavata
ameoboza
Opisthokonta
Protists’
a paraphyletic group any Eukarya that is not: plant animal fungi
Amoebozoa synapomorphies
- cell lacks cell wall
- when portions of the cell extend outword to move the cell they form large lobes
ospisthokonta
reproductive cells have a single flagellum at their bases
the cristatae inside mitochandria are flat not tubed shaped as in other eukaryotes
excavta synapomorphies
cells have a p
EUKARYOTES - DNA
Nuclear DNA - chromosomes (genome)
Mitochondrial DNA - circular genome
PRIMARY ENDOSYMBIOSIS
is the process in which a eukaryote engulfs another living prokaryote. An organism may then use that organism to its advantage. If a eukaryotic cell engulfs a photosynthetic alga cell, the larger organism can then use the products of the alga and become an autotrophic organism.
SECONDARY ENDOSYMBIOSIS
Red algal and green algal chloroplasts were transferred to other protists
red alge transferd to ALVEOLATA STRAMENOPILA
green algea transferd to EXCAVATA and rhizaria