Download - Physio1: Week 1
![Page 1: Physio1: Week 1](https://reader036.vdocuments.net/reader036/viewer/2022070302/54828a79b47959050d8b4814/html5/thumbnails/1.jpg)
Semester 1: Physiology
Body Fluid Compartmentsand
Introduction to Action Potentials
Week 1
![Page 3: Physio1: Week 1](https://reader036.vdocuments.net/reader036/viewer/2022070302/54828a79b47959050d8b4814/html5/thumbnails/3.jpg)
Compartments TBW (total body water) = 0.6BW (body
weight) ICF (Intracellular fluid) = 0.4BW ECF (Extracellular fluid) = 0.2BW
Interstitial: 0.75ECF Plasma (blood): 0.25ECF
Capillary wall separates Interstitial and Plasma sub-compartments
T-I-E = 60-40-20
![Page 4: Physio1: Week 1](https://reader036.vdocuments.net/reader036/viewer/2022070302/54828a79b47959050d8b4814/html5/thumbnails/4.jpg)
![Page 5: Physio1: Week 1](https://reader036.vdocuments.net/reader036/viewer/2022070302/54828a79b47959050d8b4814/html5/thumbnails/5.jpg)
Expansion and ContractionECF ICF Hct = RBC vol/blood vol
Hct ~ ICF/ECF
Isoosmotic volume expansion
↑ - ↓
Isoosmotic volume contraction
↓ - ↑
Hyperosmotic volume expansion
↑ ↓ ↓
Hyperosmotic volume contraction
↓ ↓ -
Hypoosmotic volume expansion
↑ ↑ -
Hypoosmotic volume contraction
↓ ↑ ↑
![Page 6: Physio1: Week 1](https://reader036.vdocuments.net/reader036/viewer/2022070302/54828a79b47959050d8b4814/html5/thumbnails/6.jpg)
Tonicity
![Page 7: Physio1: Week 1](https://reader036.vdocuments.net/reader036/viewer/2022070302/54828a79b47959050d8b4814/html5/thumbnails/7.jpg)
Determining Tonicity Need EFFECTIVE OSMOLYTE Effective osmolyte = solute that can't
cross the cell membrane; impermeant Sucrose
Ineffective osmolyte = permeable solute Urea
![Page 8: Physio1: Week 1](https://reader036.vdocuments.net/reader036/viewer/2022070302/54828a79b47959050d8b4814/html5/thumbnails/8.jpg)
π = σ(nCRT) π = Osmotic pressure
σ = reflection coefficient (0-1)
0 = ineffective osmolyte 1 = impermeant
N = dissociable particles C = total [solute] R = gas constant T = Kelvin
Determining Tonicity
![Page 9: Physio1: Week 1](https://reader036.vdocuments.net/reader036/viewer/2022070302/54828a79b47959050d8b4814/html5/thumbnails/9.jpg)
Synaptic Transmission Electrical transmission:
Gap junction (for neuron synchronization) 6 connexins = 1 connexon = ½ gap jxn Can be bi-directional Modulated by:
pH Neurotransmitters (synthesized in RER,
Golgi) Ca2+
![Page 10: Physio1: Week 1](https://reader036.vdocuments.net/reader036/viewer/2022070302/54828a79b47959050d8b4814/html5/thumbnails/10.jpg)
Synaptic Transmission Chemical Transmission:
Pre and post-synapse instead of gap jxn
Unidirectional Metabotropic receptors: slow
response via intracellular proteins) Ionotropic receptors: fast response
via depol/hyperpol ion channels
![Page 11: Physio1: Week 1](https://reader036.vdocuments.net/reader036/viewer/2022070302/54828a79b47959050d8b4814/html5/thumbnails/11.jpg)
Major Neurotransmitters Acetylcholine (Ach) Excitatory: Glutamate Inhibitory: GABA and Glycine (in vesicles) Amines:
Dopamine Norepinephrine/Epinephrine Histamine Seratonin
![Page 12: Physio1: Week 1](https://reader036.vdocuments.net/reader036/viewer/2022070302/54828a79b47959050d8b4814/html5/thumbnails/12.jpg)
Neuron ion content
![Page 13: Physio1: Week 1](https://reader036.vdocuments.net/reader036/viewer/2022070302/54828a79b47959050d8b4814/html5/thumbnails/13.jpg)
Depolarization/Action Potential Gates:
M-gate = activation gate
H-gate = inactivation gate (plug)
N-gate = slow-closing K+ channel
Temporal/Spatial Summation → Threshold
EPSP depolarization (Na+)
IPSP hyperpolarization (Cl-)
At resting state: M-gate closed, H and N-gates open
Depolarization: All gates open
Repolarization: H-gates close
After absolute refractory period: All gates closed
![Page 14: Physio1: Week 1](https://reader036.vdocuments.net/reader036/viewer/2022070302/54828a79b47959050d8b4814/html5/thumbnails/14.jpg)
Love,Julie and Jenesha