Cell Structure Flashcards
maximum resolution of light microscopy
200nm
maximum resolution of electron microscopy
0.5nm
maximum magnification of electron microscopy
2.5 x 10^5 nm
definition of resolution
the ability to distinguish two objects very close together
definition of magnification
number of times greater an image is to actual object
structure of nucleus
surrounded by two nuclear membrane with nuclear pores
function of nucleus
controlling activites in the cell
exiting out the nucleus
mRNA and ribosomes
entering the nucleus
nucleotides, ATP, ribosomes and hormones
RER (size,structure of ribosome, function)
(25nm) ribosomes made of rRNA and protein. site of protein synthesis. ribosomes don’t have membrane. cisternae found.
SER
makes lipids, steroids and hormones
golgi body (structure/function)
flattened sacs that collects, modified and sorts molecules. converts sugars to cell wall components.
size of lysosomes
0.1-0.5um with single membrane
size of mitochondria
1um
endosymbiont theory
mitochondria and chloroplasts originated from bacteria so they have 70S ribosomes and circular DNA
function of mitochondria
aerobic respiration, porin on the outer membrane, and selective inner membrane
cell surface membrane (size/function)
(7nm) controls exchange between cell and environment with partially permeability
microvilli a type of ? cell
epithelial
microtubules (size/function)
(25nm) long rigid tubules for support, transport and nuclear division
MTOCs
assembly of microtubules
microtubules formation
tubulin –> dimers –> protofilament
chloroplasts (size/function)
(3-10um) surrounded by two membrane for photosynthesis
cell wall (structure/function)
fibres of cellulose to prevent bursting
vacuole (structure/function)
plant vacuole surrounded by tonoplast. animal vacuole small and temporary. filled with salt, gases and enzymes. regulates osmotic properties.
only present in animal cells
lysosomes, centrioles, centrosomes, microvilli
only present in plant cells
plasmodesmata, chloroplasts, vacuole, cell wall
present in prokaryotes (7)
circular DNA, peptidoglycan cell wall, plasmid, 70S ribosomes, pili, capsule, flagellum
size of prokaryotes
0.5-5um
size of plant cells
40um
size of animal cells
20um
size of virus
20-300nm
conversions
mm –> um –> nm (x1000)
ATP is made of
adenine, phosphate group, ribose sugar
