Tree of Life: Domains Flashcards
What are the 5 kingdoms based on?
nutrient acquisition/visible characteristics
What are the domains based on?
genetics
LUCA
Last Universal Common Ancestor
(all life traced back to this point)
Molecular Phylogeny
evolutionary relationships based on genetic information - looking at two organism and determining relatedness based on location and differences in that genetic material
What is used in molecular phylogeny? Why?
rRNA. It is highly conserved and is basically the same for all living things, from prokaryotes to mammals
What are the three domains?
Bacteria, Archaea, Eucaria
Parts of a prokaryote cell
Cell wall
Plasma Membrane
No real organization or structure internally
Why are prokaryotes able to survive harsh environments?
Little cell structure, so less can go wrong
Bacterial plasma membranes
Lipid bilayer with fatty acids
(carbon chains - fatty acid - with glycerol head)
ends of fatty acids held together by weak attractive forces
Archaeal plasma membranes
Lipid bilayers or monolayers with phytanyl groups
(chains of methyl groups - carbon with an extra H- Bilayers held together with weak attractive forces, monolayer the same except covalently bonded)
Types of bacterial cell walls
Gram + (less complex/layers)
Gram - (more complex/layers)
What will gram + cells look like after staining? Why?
dark purple - thick inner layer of wall dehydrates during alcohol step of staining process and seals the dye inside
What will gram - cells look like after staining? Why?
pink - thin inner layer of inside wall is not able to seal the wall, so dye washes out
Cellular differentiation
process of one cell changing into another type of cell
heterocysts
differentiated cells in some cyanobacteria that allows for nitrogen fixation, when experiences nitrogen starvation
