Cell Biology Flashcards
magnification formula
(size of image)/(actual size)
conversion factor
1 mm = 1,000 micrometers
theory
a way of interpreting the natural world, allows us to make predictions
namer of cells
Robert Hooke - looking at cork through a microscope
order of cell discovery
cork cells, microscopic water, animal cells, plant cells, cells come from pre-existing cells
Postulates to cell theory
cells are fundamental building blocks of all living organisms and they come from pre-existing cells
Prokaryotic cells only
Unicellular bacteria, no contained nucleus, simple cell structure, cell wall, no organelles,
cell wall makes
peptidoglycan
Prokaryotic + Eukaryotic
surrounded by a membrane, DNA stores all instructions, chemical reactions (metabolism) catalyzed by enzymes, energy release system to power cell activities
eukaryotic only
complicated internally, compartmentalized, specialized organelles, enclosed nucleus
What is a unicellular eukaryotic?
Yeast
prokaryotic vs. eukaryotic
Bacteria and archaea vs. plant and animal,
DNA concentrated in nucleoid vs. in nucleus
Striated muscle cell
size is 30 m in length (normal is .03 mm) and has many nuclei in one cell
fungi
Uninterrupted tube with many nuclei
algae
1 microscopic cell 100 mm long with 1 nucleus
micrograph
a photo taken down a microscope
amphipathic
it has a hydrophilic and hydrophobic region
sandwich model
Davson-Danielli (1960s): phospholipid bilayer between two layers of proteins
fluid mosaic model
Singer-Nicolson (1972): membrane proteins are dispersed and inserted in the bilayer
sandwich model problems
membrane proteins are not soluble in water
Soap
amphipathic
Fluidity
drift laterally, rarely flipping, some proteins drift and some are immobile
differences in membrane fluidityq
Unsaturated tails have kinks and up membrane fluidity, cholesterol serves as a roadblock and lowers fluidity
Intergral proteins
penetrate hydrophobic core of lipid bilayer
peripheral proteins
bound loosely to the surface of the membrane
cell to cell recognition importance
in developing the embryo, the immune system, and blood groups
six membrane function proteins
Transport, Enzymatic activity, Signal transduction, cell-cell recognition, intercellular joining, attachment to cytoskeleton and ECM
transport
a protein that spans membrane and provides channel access