final terms Flashcards
(109 cards)
yeast
mating types are a and alpha, a will send out a signal and alpha has a specific receptor that will get the signal so they can mate
ligand
chemical messenger that is produced and released by one cell and then binds to a receptor for the signal to be interpreted
cell junctions
allows adjacent cells to be directly connected and pass signaling molecules
cell-cell recognition
one cell wants to pass on a message and it is beside another cell that it can interact with to send the message
paracrine signaling
no direct physical contact between cells, cells must be close but they do not have to be in direct contact
synaptic signaling
neurons release neurotransmitters that diffuse across a synapse
endocrine signaling
hormones, used mostly in animals
3 stages of cell signaling
- reception, message first reaches the receptor 2. transduction, cell has to alter the language of the message to it is easier to understand 3. response, cell makes a response out of the signal
transmembrane receptors
ligands bind to transmembrane cell surface receptor proteins (GPCR and RTK)
g protein coupled receptors GPCR
abnormal receptors are associated with disease. GDP makes it inactive, GTP makes it active
g-protein
needs to bind to GPCR to make it active. GDP inactive, GTP active
Receptor tyrosine kinases
membrane receptors that attach phosphates to tyrosines
binomial nomenclature
Carolus Linnaeus. First is genus then species within the genus
monophyletic groups
includes common ancestor and all species after it
paraphyletic
common ancestor and some of the branched species but not all
polyphyletic
does not include the common ancestor. only some of its descendant species
ancestral characters
character of a species that it shares with one or more of its ancestors
shared derived characters
character that is only unique to that specific species. is not shared with any other species or ancestor
endosymbiosis
thought that early mitochondria and protists were just prokaryotes that were living in larger host cells
Pangaea
continental drift causing all continents to come together. happened 3 times. reduced shallow water habitat, became colder and drier in the inland, changes ocean circulation leading to global warming
adaptive radiation
species branch off from common ancestor early on to adapt to new environments
continental drift
earths continents shift around via tectonic plates. happens because of underlying hot mantle, causes islands, mountains and earthquakes
cambrian explosion
sudden appearance of fossils that resemble modern phyla during the cambrian period (535-525 million years ago)
stromatolites
rock structures with bacteria in between the different layers first evidence of prokaryotes