Download The Cell Lecture Slides

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
[email protected]
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
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:
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
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: CELLENVIRONMENT 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
CYTOPLASMIC ORGANELLES
Mitochondria
Ribosomes
CYTOPLASMIC ORGANELLES
Endoplasmic Reticulum
• Smooth endoplasmic
reticulum
• Rough Endoplasmic
reticulum
CYTOPLASMIC ORGANELLES
Golgi Apparatus
• Trans face
• Cis face
CYTOPLASMIC ORGANELLES
Peroxisomes
• Neutralize free radicals
Lysosomes
CYTOPLASMIC ORGANELLES
Cytoskeleton
• Microfilaments
• Intermediate
filaments
• Microtubules
CYTOPLASMIC ORGANELLES
• Centrosome
• Centrioles
• Fig 3.25
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
MITOSIS
Prophase
•
Early Prophase
•
•
•
Chromatin condenses, forms
chromosomes
Centrosome separation, Mitotic
spindle forms
Late Prophase
•
•
•
Fig 3.33
Nuclear envelope dissolves
Spindle microtubules attach to
kinetochores at each centromere
Polar microtubules slide past each
other forcing the poles apart
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
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
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
PROTEIN SYNTHESIS
Fig 3.4
Fig 3.39
CH 3: THE CELL
Study Guide