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physiological control systems Exam
Questions With correct solutions
1.
homeostasis:
ability
of
body
to
maintain
relatively
constant
(stable)
internal
environment
2.
list
of
variables:
created
by
Walter
b.
cannon:
ionic composition of fluids
body temp
pH of body fluids
plasma
glucose conc
BP
hormones
3.
each variable has a: set point or optimal value
can be a
range
ex.
temp
=
~98.6
4.
components of control system: sensor - measures controlled variable
integrating center -
compares sensor value to set point
output
signal
onto
effector
-
mechanism
creates
response
and
adjusts
controlled
variable
error signal - represents
output of integrator if sensor value not at set point
5. normal set point variation occurs
as
a result of:
biological rhythms
ex. temp lowest
in morning, plasma cortisol lowest during sleep
6. abnormal set points
(i.e.
fever) can be introduced during:
disease states such as
infection (microbes,
virus, pathogens) and hypertension
