General Physiology Flashcards
Environments
- intracellular
- extracellular
I: K+, mostly water
E: Na+, blood plasma + interstitial fluid
Membrane potential
- function of
- normal
Electrical charge and chemical concentration gradient
-90mV (same as equilibrium potential)
[K+] within cell > ECF
Resting membrane potential
-65 to -85mV
Due to pumps: 2K+ in, 3Na+ out
Depolarization
Hyperpolarization
Action potential
Depol = inside cell becomes more positive than resting state, due to influx of Na+
Hyperpol: inside cell becomes less positive than resting state, due to efflux of Na+
AP: when membrane is depolarized beyond a certain threshold
Adrenoreceptor actions
Alpha1: incr IP3 = incr Ca2+
Alpha2: inhibits adenylyl cyclase = decr cAMP
Beta1: stimulates adenylyl cyclase = incr cAMP
Beta2: stimulates adenylyl cyclase = incr cAMP
Cholinoreceptor actions
Nicotinic: opens Na+/K+ channels = depol
Muscarinic: incr IP3 = incr Ca2+
Body fluids
- intracellular
- extracellular
ICF: 25L = K+
ECF: 15L
- 12L interstitial fluid = Na+
- 3L plasma = Na+ and protein
ICF and ECF have same osmolality, ICF slight more acidic
Diffusion is a form of __ and utilizes __ energy from molecules
Passive transport
Thermal energy
Simple diffusion
- inorganic ions
- steroid hormones and other lipids
Specific channels
Pass straight thru
Which part of the lungs are innervated by B2
Conducting zone
- upper airways, trachea, bronchi, bronchioles
- warms and humidifies
Normal to elevated FEV1/FVC ratio
Restrictive lung dz
-toxo, histo, sarcoid
Dead space
- anatomic
- functional
- physiologic
A: in conducting zone (bronchi/oles)
F: in alveoli
P: anatomic + functional
Area of lungs with highest blood flow and oxygen exchange
Base of lungs
CO2 in the body
20x more CO2 than oxygen in our body, 90% as bicarb
Emphysema - really basic
Decr surface area of lungs
Hemoglobin binding oxygen
Cooperative - once one O2 molecule binds, it can more easily bind to additional O2 molecules
-sigmoidal shape of oxygen dissociation curve
—shift right = less capable of binding O2 (e.g. decr pH, incr temp/CO2)
—shift left = more readily binds O2 (e.g. incr pH, decr temp/CO2)
Breathing control
Neural and chemical
- N: medulla oblongata
- C: carotid and aortic bodies, via pH (O2/CO2 levels)
ERG
- systole
- diastole
S: Q-T
D: T-R
Heart sounds
- S1
- S2
S1: mitral, tricuspid close
S2: aortic, pulmonary close
“Try My
Apple Pie”
Action potentials
- fast myocardial
- slow myocardial
Fast: everywhere but SA/AV nodes; Na+, K+
Slow: SA/AV nodes; Ca2+
Starling forces
(-Jv) Favors absorption (into BV): capillary oncotic pressure, tissue hydrostatic pressure
(+Jv) Favors filtration (into tissue): tissue oncotic pressure, capillary hydrostatic pressure
BP neural regulators: baroreceptors
Aortic arch (CN10) Carotid sinuses (CN 9)
Via SNS
To medulla oblongata
Cardiac output equation
Strove volume x heart rate
Affects of digitalis
Incr intracellular Na+ = incr stroke volume + contractility
