Physiology notes
Physiology studies the functioning of the body
Integrative physiology
Perception of the stress stimulus in the brain activation of the fight-
flight response
Activation of brain areas involved in release of energy and
stimulation of cardiovascular system.
Communication between brain and body: neurotransmitters and
hormones
Bushmen’s physiology
Adrenalin , sympathetic nervous system
Sympathetic nervous system works unconsciously, prepares the
body to deal with fear and stress.
Activation of several processes in the body
o Pancreas inhibits release of insulin
o Liver stimulates glucose release
o White adipose tissue releases fatty acids
o Heart rate and blood pressure goes up
More energy available and changes in blood distribution
ACTH (stimuleert bijnierschors) and cortisol goes up
Inhibition of irrelevant processes
Fight / flight: released glucose and fatty acids are used by active muscle
No fight / flight: there is stress and elevated levels, but the body does not
use it. Chronic higher blood pressure, storage of fat in the endothelium
(FFA gets stuck)
- Adrenaline = epinephrine
Immune system is reduced when stressed more viable for diseases.
- Physiology: processes go right
- Pathophysiology/pathology: processes go wrong
Homeostasis: your body its biochemicals are in balance and normal
- Feedback mechanisms
- Internal milieu: baseline of what the body wants to get back to
- Setpoint: normal levels of chemicals
- Failure of homeostasis pathology. Organism tries to compensate
(failure = illness)
- Negative feedback: Stimulus is seen by sensor, integrating centre
compares to setpoint and sees the problem and activates the
effector, which produces a response to get it back to setpoint
- Integrating centre = compares conditions to set point
- Effector = systems that change to compensate for deviation.
Multiple possible
- Response counteracts the stimulus, shuts off response loop.
- Response loop = a loop created by measurements of
concentrations etc.
- Circadian rhythmicity: physical, mental, and behavioural changes
that follow a 24-hr cycle, like body temperature.
Physiology studies the functioning of the body
Integrative physiology
Perception of the stress stimulus in the brain activation of the fight-
flight response
Activation of brain areas involved in release of energy and
stimulation of cardiovascular system.
Communication between brain and body: neurotransmitters and
hormones
Bushmen’s physiology
Adrenalin , sympathetic nervous system
Sympathetic nervous system works unconsciously, prepares the
body to deal with fear and stress.
Activation of several processes in the body
o Pancreas inhibits release of insulin
o Liver stimulates glucose release
o White adipose tissue releases fatty acids
o Heart rate and blood pressure goes up
More energy available and changes in blood distribution
ACTH (stimuleert bijnierschors) and cortisol goes up
Inhibition of irrelevant processes
Fight / flight: released glucose and fatty acids are used by active muscle
No fight / flight: there is stress and elevated levels, but the body does not
use it. Chronic higher blood pressure, storage of fat in the endothelium
(FFA gets stuck)
- Adrenaline = epinephrine
Immune system is reduced when stressed more viable for diseases.
- Physiology: processes go right
- Pathophysiology/pathology: processes go wrong
Homeostasis: your body its biochemicals are in balance and normal
- Feedback mechanisms
- Internal milieu: baseline of what the body wants to get back to
- Setpoint: normal levels of chemicals
- Failure of homeostasis pathology. Organism tries to compensate
(failure = illness)
- Negative feedback: Stimulus is seen by sensor, integrating centre
compares to setpoint and sees the problem and activates the
effector, which produces a response to get it back to setpoint
- Integrating centre = compares conditions to set point
- Effector = systems that change to compensate for deviation.
Multiple possible
- Response counteracts the stimulus, shuts off response loop.
- Response loop = a loop created by measurements of
concentrations etc.
- Circadian rhythmicity: physical, mental, and behavioural changes
that follow a 24-hr cycle, like body temperature.
