Download Eukaryotic Cells - MrsGorukhomework

Eukaryotic Cells - liver cell is the example
Both plant and animal cells
Endosymbiotic theory – possible origin of Eukaryotic cells. Prokaryotes,
mitochondria and chloroplasts existed separately. Prokaryotes engulfed either
one or both to live in symbiotic relationship. Evidence –mitochondria and
chloroplasts have own DNA, certain organelles have double membranes –
emergent properties
Importance of compartmentalization – provides different local environments that
facilitate a specific metabolic function. Processes that are incompatible can
occur simultaneously in separate areas, needs membrane-bound organelles.
Ultrastructures – cell anatomy seen under the microscope
Be able to draw and recognize** nucleus has double membrane with pores,
mitochondria has double membrane with inner folding, Golgi are curved
stacked tubes with small vesicles near ends, ribosome’s both attached and
free
Nucleus – contains genetic material (NOT ‘controls’ the cell)
Nuclear membrane – with pores, nucleolus – produces ribosomes
Chromatin – DNA with proteins called histones, chromosomes (later) All
eukaryotes have DNA and protein histones. Eg. What are the chromosomes of
fungi made up of?
A. DNA
C. DNA and RNA
B. DNA and proteins
D. DNA, RNA and proteins
E.R. – site for protein synthesis, smooth ER does not have ribosomes attached
and contains enzymes that do some metabolism, rough ER has ribosomes
attached. (sedatives like Phenobarbital and alcohol cause more smooth ER to be
made and therefore more enzymes. This increases tolerance and requires more
of the drug.
Golgi apparatus – modifies proteins double membraned (looks like pita bread)
Ribosomes – two types; a) free which are not bound to ER, make proteins for
internal cell use 2) attached found on ER, which make proteins for use outside
the cell.
*Vesicles form around them and carry to Golgi to be processed and then a
vesicle moves to cell membrane, fuses and expels protein through exocytosis.
Lysosomes – sacs of enzymes that digest macromolecules (works best at low ph
– 5) double membrane, self-death
Cell membrane (plasma membrane) – selectively permeable
Mitochondria – site of cellular respiration, has own DNA, (and ribosomes) can
have hundreds based on need, double membraned
Chloroplasts – own DNA, contains chlorophyll, belongs to a bigger group called
plastids, double membraned
Cytoplasm – entire region between nucleus and cell membrane –cytoskeleton
runs through it.
Cytoskeleton – network of three types of fibers; microtubules, microfilaments and
intermediate fibers. Microtubules involved with muscles, microtubules made up
of globular proteins called tubulin. Responsible for shape and support of cell and
involved in separating chromosomes during mitosis.
Cytosol – fluid in cytoplasm
Vesicles – only formed when needed
Plants have large, permanent central vacuole or storage and growth, cell wall
made of cellulose which contains bundles of microfibrils, more regular shaped.
Role of extracellular components – cell wall which maintains cell shape, prevents
excessive water uptake, holds plant up against gravity
Animal cells have glycoprotein’s that form extra cellular matrix for support,
adhesion, movement
Be able to compare prokaryotes and Eukaryotes and plant and animal.
Could include the internal membranes that allow for compartmentalization
*micrographs – may 06 had ER looks different than Golgi - check
Remember – even in compare give differences first then similarities.
Prokaryotes
Naked DNA
70s ribosomes
No distinct nucleus
No membrane-bound organelles
Circular chromosomes
Fission
No introns or exons
Smaller about 10 microns
Cell wall
Eukaryotes
DNA with proteins (histones)
80s ribosomes
Nucleus and nuclear membrane
Internal membranes forming membrane
bound organelles
Linear chromosomes
Mitosis
Intron and exons
Larger about 100 microns
Only plants have cell wall