Transcript cell physiology - people.vcu.edu

CELL
PHYSIOLOGY
CELLS ARE THE BASIC UNIT
OF LIFE
CELL ORGANELLES
Mitochondrion
Nucleus
CELL ORGANELLES
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Cell Membrane
Nucleus
Endoplasmic reticulum
Golgi complex
Mitochondria
Lysosomes
Microfilaments and microtubules
Vesicles
THE NUCLEUS
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Site of DNA (In
chromosomes)
Enclosed by a
membrane
DNA REPLICATION
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The double helix
“unzips”
New bases pair
up with the old
ones
The molecule
replicates itself
Two identical
copies each with
one old strand
and one new
RNA TRANSCRIPTION
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Messenger RNA
“copies” from
DNA
m-RNA caries the
message to the
rough ER
ENDOPLASMIC
RETICULUM
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Fluid filled membrane system
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Rough ER: Protein Synthesis
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Smooth ER: Synthesis of Lipids
Rough ER : Site of
Protein Synthesis
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Rough ER contains ribosomes
M-RNA attaches to ribosome
A triplet of bases is a Codon
Transfer RNA has an anticodon at
one end and the appropriate amino
acid at the other
As the code is read, amino acids
are assembled into a protein
ER -> Golgi -> Secretion
Exocytosis
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Vesicles fuse with the membrane
They open to the outside and
discharge their contents
MITOCHONDRIA
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Extract Energy from Food Fuels
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Energy is stored in ATP
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Aerobic Metabolism
Anaerobic Metabolism
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Sugar can be burned without
oxygen - anaerobically
Far more energy released from
burning sugar aerobically
Glycolysis is anaerobic-carried out
in cytosol
Glucose ----> 3 Carbon fragments
plus 2 ATP
Aerobic Metabolism
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Pyruvic Acid (3 C fragment) enters
Mitochondria
Combines with Coenzyme A
loosing a CO2 and becoming Acetyl
Coenzyme A (2 C fragment)
This fragment enters a cyclic
reaction scheme, the Citric Acid
Cycle
Ultimately, 34 more ATP’s are
produced
THE CYTOSKELETON
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Microtubules
Microfilaments
Intermediate Filaments
Microtubular Lattice