principles of phys Flashcards
R. heart vs L. heart
R. heart is deoxygenated blood that takes low pressure blood to the lung to get O2 and get rid of CO2
L. heart accepts oxygenated blood and pushes it out at high pressure to body tissues
organization of body
kidney takes out the junk (urine)
Endocride glands put hormones into the blood
Liver helps synthesis and metabolism
GI tract absorbs and defecates
Peripheral nervous system
Afferent: somatic (touch), viceral (something is wrong in organ), special (sight)
Efferent: somatic (moves hand), autonomic (sympathetic, parasympathetic, enteric
Somatic PNS
-a single neuron between CNS and muscle
Autonomic PNS
2 neuron chain between CNS and efector organ
innervates smooth and cardiac muscle, glands, GI, NOT skeletal muscle
can be excitatory or inhibitory
ANS
para symp has long pre and shrt post
sym has short pre then long post
Homeostasis
Constancy of internal environment- maintained by feedback loops that detect and correct a deviation of set point
Control mechanims and feedback:
Neg feedback: system returns back to normal
Pos feedback: stimulus causes system to more of the same (vicious cycle)
Gain equation
Gain=correction/remaining error
with help- without help) / (with help - normal
Decrease body temp
smooth muscle in skin blood vessels contract to minimize heat loss
Skeletal muscle contracts shivering byt increasing heat production
Baroreceptor reflex
Baroreceptor senses pressure change, stimulates brain medulla vasomotor center –> sympathetic NS–> blood vessels will change according
if there are no baroreceptors bp goes up bc the brain senses that there is 0 blood pressure
Mass balance
essentially what goes in must come out
stable state Gain is equal to the loss
Tissue exchange
Simple diffusion, facilitated diffusion, active transport
Secondary active transport
Co transport: when one solute goes from high to low, and carries another INTO the cell against concentration gradient
Counter transport: when one solute goes from high to low, and carries another OUT OF the cell against concentration gradient
Hematocrit Hct
its the percentage of red blood cell mass to the whole blood, so if only plasma goes up hct goes down, if everything is lost (ie bleeding ) hct stays the same
Metabolism
Substances are cleared from blood specifically the rate that its done at is the metabolic clearance rate MCR
The higher the MCR, the faster something is cleared and the shorter the half life
