Cell Bio- Microscopy

light microscopy

resolution= 2um
for dead and alive subjects

alive (different optics)

dead(staining)

sample ~thin/transparent

allows examination of cells and some of their content

three types of light microscopy

bright field optics
phase contrast optics
interference contrast optics

brightfield optics

low contrast

usually need staining

phase contrast optics

observing living cells

halo effects

interference contrast optics

3d like image, no halo

expensive

fluorescence microscopy

resolution=.2um

cellular structures labeled by dyed/antibodies

glowy-like effect

confocal microscopy

type of fluorescence microscopy

resolution=.2um

3D like image

ideal of live/thicker samples

super resolution microscopy

resolution=10-20 nm

insight into intracellular processes

electron microscopy

major cell biology breakthrough

100x better resolution than light microscopy

2 types: TEM/SEM

Transmission Electron Microscopy (TEM)

Resolution=1nm

electrons and magnets used to create/focus image

dead samples sectioned and stained for contrast

scanning electron microscopy (SEM)

resolution= 3-20nm

heavy metal coated, dead samples are scanned by electron bean

3-D like image

nucleus

contains nuclear envelope

contains nuclear pores

transcription and RNA processing occurs in

the nucleus

translation of mRNA into proteins @ ribosomes occurs in the

cytosol after mRNA exports through nuclear pores

ER contain flattened or tubular sacs called

cisternae

lysosomes

molecular digestion of biomolecules

peroxisomes

hydrogen peroxide chemistry for breakdown/synthesis of moleculessm

small vesicles

transport components throughout cell

endosomes

sorts components brought into cells via endocytosis

actin filaments

thinnest, cell shape, muscle contration, intracellular transport

microtubules

thickest, hollow tubes, cell division & intracellular transport

intermediate filaments

widespread & diffuse for strength & support.