Lectures Scheurink
Integrative physiology, homeostasis and communication
The selfish gene: the organism exists and functions so that the genes can survive beyond the mortal
life of individual members of a species
Physiological mechanisms
Survival of the individual:
- Stay alive
- Growth
Survival of the species:
- Reproduction
- Care
Fight/flight response: autonomic and physiological responses
➔ Stay alive, first requirement
Signal coming from the brain to different organs
Adrenal (on top of the kidney) produces hormones (adrenalin) released into the blood stream →
increases heart frequency + cardiac output → release energy
Second response: Cortex releases cortisol
Physiology: studies the functioning of the body
- Molecular level
- Organ level
- Interactions between organisms and the environment
1. Integrative physiology
→ organs working together
- Perception of the stress stimulus in the brain → activation of the fight-flight response
- Activation of brain areas involved I the release of energy substrates and the stimulation of
the cardiovascular system
- Communication between brain and body through chemical messengers: neurotransmitters
and hormones
- Adrenalin ↑ → sympathetic nervous system ↑
- Activation of several processes in the body
Pancreas → insulin ↓, liver → glucose release
White adipose tissue → release of fatty acids
Heart rate ↑ and blood pressure ↑
- Increased availability of energy substrates and changes in blood distribution
- ACTH and cortisol ↑
- Inhibition of irrelevant processes, a.o. the gut and the immune system
Fight/flight; released glucose and FFAs are utilized by the active muscle
No fight/flight: pathological condition
Adrenal(top of the kidney) produces hormones
Adrenaline; activates blood circulation, increase heart frequentie
If physiology goes wrong → become sick
Stress (patho)physiology
,Individual differences → same task → difference responses
Stress situations associated with elevated adrenalin and noradrenalin levels, increased heart rate and
blood pressure, release of glucose and FFAs
- Speaking in public
- Parachute training
- Erotic movies, thrillers, horrors
- Exam
- Hypnosis (fear, exercise)
- Homeostasis
➔ Feedback mechanisms (balance)
- Feedback
- Setpoint: body returns always to this point
- Failure of homeostasis (pathology)
The effect of food deprivation and forced overfeeding is compensated
- Negative feedback: the response counteracts the stimulus,
shutting off the response loop
Initial stimulus → response → stimulus
- Negative feedback loop:
, - Positive feedback: the response reinforces the stimulus, sending the variable farther from
the setpoint
Integrative physiology and homeostasis: bodily functions are integrated
➔ Requires communication
➔ Ways of communication:
o Nervous system
o Blood
o Lymph
o Air
o Water
➔ Communication tools:
o Neurotransmitters
o Hormones
o Pheromonen
Chemical messengers and regulatory factors:
- Autocrine:
- Paracrine:
-
- Endocrine: done by hormones,
- Neuroendocrine:
- Neurotransmission:
Insulin: hormone released in the bloodstream, travelling to the organs (endocrine/paracrine)
CCK(hormone) is released in the gut after a meal
- Paracrine: activating enzyme
- Endocrine: release of insulin by the pancreatic B-cell
- Neural: stimulation of the afferent neurons of the parasympathetic nervous system →
satiation
Communication between individuals → pheromones
- Androsterone: reproductive signal
released into the air
, Vomeronasal organ, makes it possible to have sex
➔ Hole in the nose
➔ The same menstruation cycle, was synchronized when the girls like each other
➔ Signal comes in but always brain area that can decide to ignore or not
The nervous system
- Central nervous system (CNS)
o Brain, in the skull
o Spinal cord, in the spine
- Peripheral nervous system (PNS)
➔ Located outside of the skull and spine
➔ Serves to bring information into the CNS and carry signals out of the CNS
o Somatic nervous system
▪ Afferent nerves (to the brain)
▪ Efferent nerves( down to the body)
▪ Muscles can be activated
o Autonomic nervous system
▪ Sympathic and parasympathic nerves
▪ Both afferent and efferent nerves
▪ Goes autonomically
-
-
System that is rules by the brain
- Store energy: nerves assimilateurs
- Release energy: nerves desassimilateurs
Autonomic nervous system
- Innervates those systems that cannot be controlled by the conscious brain such as heart,
smooth muscle, blood vessels, most visceral organs and all endocrine glands
- Nervous parasympathetic and sympathetic system
- All the organs in the belly that work automatically
- Controlled by the brain but don’t notice it
Plays an important role in the integration of peripheral body functions
Integrative physiology, homeostasis and communication
The selfish gene: the organism exists and functions so that the genes can survive beyond the mortal
life of individual members of a species
Physiological mechanisms
Survival of the individual:
- Stay alive
- Growth
Survival of the species:
- Reproduction
- Care
Fight/flight response: autonomic and physiological responses
➔ Stay alive, first requirement
Signal coming from the brain to different organs
Adrenal (on top of the kidney) produces hormones (adrenalin) released into the blood stream →
increases heart frequency + cardiac output → release energy
Second response: Cortex releases cortisol
Physiology: studies the functioning of the body
- Molecular level
- Organ level
- Interactions between organisms and the environment
1. Integrative physiology
→ organs working together
- Perception of the stress stimulus in the brain → activation of the fight-flight response
- Activation of brain areas involved I the release of energy substrates and the stimulation of
the cardiovascular system
- Communication between brain and body through chemical messengers: neurotransmitters
and hormones
- Adrenalin ↑ → sympathetic nervous system ↑
- Activation of several processes in the body
Pancreas → insulin ↓, liver → glucose release
White adipose tissue → release of fatty acids
Heart rate ↑ and blood pressure ↑
- Increased availability of energy substrates and changes in blood distribution
- ACTH and cortisol ↑
- Inhibition of irrelevant processes, a.o. the gut and the immune system
Fight/flight; released glucose and FFAs are utilized by the active muscle
No fight/flight: pathological condition
Adrenal(top of the kidney) produces hormones
Adrenaline; activates blood circulation, increase heart frequentie
If physiology goes wrong → become sick
Stress (patho)physiology
,Individual differences → same task → difference responses
Stress situations associated with elevated adrenalin and noradrenalin levels, increased heart rate and
blood pressure, release of glucose and FFAs
- Speaking in public
- Parachute training
- Erotic movies, thrillers, horrors
- Exam
- Hypnosis (fear, exercise)
- Homeostasis
➔ Feedback mechanisms (balance)
- Feedback
- Setpoint: body returns always to this point
- Failure of homeostasis (pathology)
The effect of food deprivation and forced overfeeding is compensated
- Negative feedback: the response counteracts the stimulus,
shutting off the response loop
Initial stimulus → response → stimulus
- Negative feedback loop:
, - Positive feedback: the response reinforces the stimulus, sending the variable farther from
the setpoint
Integrative physiology and homeostasis: bodily functions are integrated
➔ Requires communication
➔ Ways of communication:
o Nervous system
o Blood
o Lymph
o Air
o Water
➔ Communication tools:
o Neurotransmitters
o Hormones
o Pheromonen
Chemical messengers and regulatory factors:
- Autocrine:
- Paracrine:
-
- Endocrine: done by hormones,
- Neuroendocrine:
- Neurotransmission:
Insulin: hormone released in the bloodstream, travelling to the organs (endocrine/paracrine)
CCK(hormone) is released in the gut after a meal
- Paracrine: activating enzyme
- Endocrine: release of insulin by the pancreatic B-cell
- Neural: stimulation of the afferent neurons of the parasympathetic nervous system →
satiation
Communication between individuals → pheromones
- Androsterone: reproductive signal
released into the air
, Vomeronasal organ, makes it possible to have sex
➔ Hole in the nose
➔ The same menstruation cycle, was synchronized when the girls like each other
➔ Signal comes in but always brain area that can decide to ignore or not
The nervous system
- Central nervous system (CNS)
o Brain, in the skull
o Spinal cord, in the spine
- Peripheral nervous system (PNS)
➔ Located outside of the skull and spine
➔ Serves to bring information into the CNS and carry signals out of the CNS
o Somatic nervous system
▪ Afferent nerves (to the brain)
▪ Efferent nerves( down to the body)
▪ Muscles can be activated
o Autonomic nervous system
▪ Sympathic and parasympathic nerves
▪ Both afferent and efferent nerves
▪ Goes autonomically
-
-
System that is rules by the brain
- Store energy: nerves assimilateurs
- Release energy: nerves desassimilateurs
Autonomic nervous system
- Innervates those systems that cannot be controlled by the conscious brain such as heart,
smooth muscle, blood vessels, most visceral organs and all endocrine glands
- Nervous parasympathetic and sympathetic system
- All the organs in the belly that work automatically
- Controlled by the brain but don’t notice it
Plays an important role in the integration of peripheral body functions
