exam II Flashcards
(55 cards)
prokaryotes vs eukaryotes
prokaryotes - circular DNA and don’t have a nucleus, eukaryotes are larger and DNA in linear form stored in membrane enclosed nucleus
light microscope
glass lenses that magnify image by focusing a beam of photons [max: 1000x] [resolution: µm] [smallest thing you can see: bacterium]
electron microscope
magnetic lenses that focus a beam of electrons [max: 100,000x] [resolution: 1nM] [smallest thing you can see: molecules]
how do gases exit/enter cell?
diffusion across membrane
diffusion
movement from high concentration to low; rate limited by surface area
DNA + protein =
chromatins
all cells have:
plasma membrane, chromosomes, ribosomes
plasma membrane =
phospholipid bilayer perimeter
ribosomes =
special proteins + rRNA ; location of protein synthesis
where is ribosomal RNA made?
nucleolus
transcription
DNA -> RNA [myosin protein]
translation
RNA -> protein [ribosome]
rough ER
binding sites for ribosomes, collecting proteins, protein synthesis
smooth ER
makes membrane, work surface for chemical reactions, no docking sites for ribosomes
endomembrane system (outside of nucleus)
prepares proteins for secretion
golgi apparatus =
protein trafficker
phosphate head is…
hydrophilic, polar, anion
hydrocarbon tail is…
hydrophobic, nonpolar
passive transport
no energy needed, diffusion, trying to create equilibrium
active transport
energy needed, low to high concentration, pushes against gradient
osmosis
diffusion of water across a selectively permeable membrane
tonicity
a solution’s ability to gain or lose water
isotonic
equal tonicity
hypotonic
less tonicity than…
