Transcript Cell Powerpoint used in class

Cytology
Cell Theory
• All living things are
made up of at least
one cell
• Cells are the basic
units of structure and
function in an
organism
• Cells only come from
the reproduction of
other cells
Prokaryotic Cells
• Bacteria
• Extremely tiny (1-5 m)
• Contain DNA, but lack
nucleus
• Only has a cell
membrane-- no
membrane bound
organelles
Eukaryotic Cell
• Separate Domain than
prokaryotes
– Most fundamental
difference in classification
• Contain many membrane
bound organelles
• 10-100x larger than
prokaryotes
• Plants, Animals Fungi,
Protists
Cytoplasm
• Portion of the cell
outside the nucleus
• Fluid inside of the cell
• Water based solution
• Nutrients needed for
life dissolved inside
cell
• Includes organelles
Nucleus—Control Center
• Contains the cell’s DNA—
genetic code
– DNA bound in chromatin
– Chromatin: thread like
structure of Protein and
DNA
• Instructs cell how to make
proteins
• Enclosed by Nuclear
Envelope-- a membrane
– Contain nuclear pores-allow certain materials to
pass in and out of nucleus
• Nucleolus—dense
structure where
ribosomes are assembled
Ribosomes
• Where proteins are
assembled
• No membrane (also
found in prokaryotes)
• Made of RNA (ribose)
and protein
• Can be either free floating
or attached to
endoplasmic reticulum
• Extremely tiny
Endoplasmic Reticulum (ER)
• Transport network
• Moves molecules to
different parts of the cell
• System of membranes
• Rough ER-Ribosomes
attached
• Easily transport newly
synthesized proteins
• Smooth ER– no ribosomes
• Transport of other
molecules
Golgi Apparatus
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
• Modification and
packaging of molecules
• Helps move materials
into and out of cells
• Works closely with ER
• Stack-like membranes
• Form vessicles
– membrane bound sacs
which hold material and
move throughout the cell
Lysosome
• Membranes that contain enzymes that break
apart various molecules
• Digestion or clean up
• Vessicles that contain enzymes
Vacuole (mostly plants)
• Large storage sacs
for water, salts,
proteins, and
carbohydrates
• Pressure of large
vacuoles allows
plants to support
large structures (i.e.
leaves, flowers, etc)
Mitochondria
• Mitochondrion (s.),
mitochondria (pl.)
• Transfer energy stored in
carbohydrates (and other
organic molecules) into
ATP.
• Contain DNA
• Bound by double
membrane
– Inner membrane folds to
form christae
• Inherited from mother
• Likely formed from
prokaryotes living within
another cell-endosymbiotic theory
Plastids (mostly plants)
• Most common is chloroplast
– Transform solar energy into
chemical energy—
photosynthesis
– Contain chlorophyll—green
pigment
– Thylakoid-- flat membranous
sac where photosynthesis
occurs
• Contain DNA
• Bound by a double
membrane
• Likely originally prokaryotic
cell that lived within another
(eukaryotic) cell
Cytoskeleton
• Gives cell shape and
structure, also allow for
movement
• Network of protein
filaments—microtubules
– Support cell and transport
materials
– Also form cilia and flagella–
structures for propulsion
• Microfilaments
– Smallest fibers, allow for
movement of cell