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HUMAN ANATOMY AND PHYSIOLOGY I Lecture: M 6-9:30 Randall Visitor Center Lab: W 6-9:30 Swatek Anatomy Center, Centennial Complex
Required Text: Marieb 9th edition
Dr. Trevor Lohman DPT (949) 246-5357
THE CELL
CH. 3: THE FUNCTIONAL UNIT OF LIFE
THE CELLULAR BASIS OF LIFE The Smallest Living Unit Cell Theory: Generalized or Composite Cell • Plasma Membrane • Cytoplasm • Nucleus
Fig 3.2
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THE PLASMA MEMBRANE: STRUCTURE The Fluid Mosaic Model Membrane Lipids
• Phospholipids
• Glycolipids
• Cholesterol
• Lipid Rafts • Fig 3.3
PLASMA MEMBRANE: STRUCTURE Membrane Proteins: • Integral Proteins
• Peripheral Proteins
• The Glycocalyx
• Fig 3.3-3.4
CELL JUNCTIONS Tight Junctions:
Desmosomes:
Gap Junctions:
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THE PLASMA MEMBRANE: MEMBRANE TRANSPORT Passive Processes • Osmosis
• Aquaporins • Osmolarity • Hydrostatic vs. osmotic pressure • Tonicity (Iso, Hyper, Hypo) • Fig 3.9
• Diffusion • Simple diffusion • Facilitated diffusion • Carrier-Mediated facilitated diffusion • Channel-Mediated facilitated diffusion • Fig 3.6, 3.7, 3.8
THE PLASMA MEMBRANE: MEMBRANE TRANSPORT Active Transport • Primary Active Transport (3.10)
• Sodium-potassium pump • Secondary Active Transport (3.11)
• Symport system vs. antiport system • Vesicular Transport (3.12- 3.13)
• Endocytosis, Transcytosis, Vesicular Trafficking Fig 3.12 • Phagocytosis • Pinocytosis • Receptor Mediated endocytosis • Exocytosis
THE PLASMA MEMBRANE: GENERATION OF A RESTING MEMBRANE POTENTIAL
Membrane Potential and Resting Membrane Potential Selective Diffusion Establishes Membrane Potential • Fig 3.15
• Step 1 • Step 2 • Step 3
Active Transport Maintains Electrochemical Gradients
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THE PLASMA MEMBRANE: CELL-ENVIRONMENT INTERACTIONS
Roles of Cell Adhesion Molecules • Molecular Velcro • The “arms”
• Send SOS signals
• The Mechanical Sensors
• The Transmitters of intracellular signals
THE PLASMA MEMBRANE: CELL-ENVIRONMENT INTERACTIONS Roles of Plasma Membrane Receptors • Contact Signaling • Chemical Signaling
• Ligands • Catalytic receptor proteins • Chemically gated channel-link
receptors • G-linked receptors
• Second messengers • Cyclic AMP • Ionic calcium • Fig 3.16
THE CYTOPLASM The Cytosol
Organelles
Inclusions
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CYTOPLASMIC ORGANELLES Mitochondria
Ribosomes
CYTOPLASMIC ORGANELLES Endoplasmic Reticulum
• Smooth endoplasmic reticulum
• Rough Endoplasmic reticulum
CYTOPLASMIC ORGANELLES Golgi Apparatus • Trans face • Cis face
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CYTOPLASMIC ORGANELLES Peroxisomes • Neutralize free radicals
Lysosomes
CYTOPLASMIC ORGANELLES Cytoskeleton • Microfilaments
• Intermediate filaments
• Microtubules
CYTOPLASMIC ORGANELLES
• Centrosome
• Centrioles
• Fig 3.25
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THE NUCLEUS The Nucleus • Multinucleate • Anucleate 3 distinguishable regions • The Nuclear Envelope
• Nuclear Pores • Nucleoli • Chromatin
• 30% DNA • 60% globular histone proteins • 10% RNA chains • Nucleosomes • Chromosomes
CELL CYCLE: INTERPHASE/M-PHASE Interphase (Metabolic/Growth Phase) • Subphases
• G1 (gap 1 subphase)/(G0 phase)
• S Phase • G2 (gap 2 subphase)
• DNA Replication
• Enzymatic Unwinding • Replication bubble
forms • RNA Primer Formation • DNA Polymerase
CELL DIVISION Cell Division • M (mitotic) phase
• Mitosis • Prophase • Metaphase • Anaphase • Telophase
• Cytokinesis
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MITOSIS Prophase • Early Prophase
• Chromatin condenses, forms chromosomes
• Centrosome separation, Mitotic spindle forms
• Late Prophase • Nuclear envelope dissolves • Spindle microtubules attach to
kinetochores at each centromere • Polar microtubules slide past each
other forcing the poles apart
Fig 3.33
MITOSIS Metaphase • Centromeres are at
opposite poles of the cell • Chromosomes align along
the equator of the spindle or metaphase plate
• Enzymatic separation of chromatids begins
ANAPHASE • Shortest Mitotic Phase • Begins with simultaneous
chromatid separation • Motor proteins within the
kinetochores pull chromosomes toward the poles
• Polar microtubules continue to expand, pushing the poles further apart
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TELOPHASE • Begins when
chromosomal movement stops
• Resembles prophase in reverse
• Chromosomes unravel and revert to chromatin
• New nuclear envelopes form and nucleoli reform
• Mitotic spindle disappears • Mitosis ends, and cell is
now binucleate
CYTOKINESIS • Actin ring forms and
constricts until cell is pinched in two
• Begins during late Anaphase
• Continues beyond Telophase
PROTEIN SYNTHESIS Deoxyribose Nucleic Acid • DNA is the master
blueprint • Composed of 4 nucleotide
bases A, T, C, G • Triplets code for
individual amino acids • Exons and introns
• DNA is useless without RNA
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PROTEIN SYNTHESIS RNA • Messenger RNA (mRNA)
• The “transcript” from which protein synthesis is performed
• Ribosomal RNA (rRNA) • Building block of
ribosomes • Transfer RNA (tRNA)
• Transport cytoplasmic amino acids to ribosomes
PROTEIN SYNTHESIS Transcription • Initiation
• RNA Polymerase • Promoter • Helix pulled apart
• Elongation • Helix unwound and
rewound and as mRNA formed
• Termination • Termination signal • mRNA separation
PROTEIN SYNTHESIS Translation • Nucleic acid language translated to
amino acid language • Codons (64 possible)
Translation Events • Initiation
• Ribosomal subunit binds to initiating tRNA which scans for start codon
• Elongation • Codon recognition • Peptide bond formation • Translocation
• Termination • Stop codon reached • Polypeptide chain released
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PROTEIN SYNTHESIS Fig 3.4 Fig 3.39
CH 3: THE CELL Study Guide
