Homeostasis
Homeostasis
The ability for the body to maintain a relatively stable internal condition
Dynamic state of equilibrium: when internal conditions may vary within relatively narrow
limits of one another
- Occurs despite the outside continuously changing
Every organ system will play a role in the maintenance of the constancy of the internal
environment
Homeostatic control: communication within the body that is essential to maintain
homeostasis (nervous or endocrine system)
- Communication is mainly accomplished by the nervous and endocrine systems as
they use electrical impulses / bloodborne hormones as information carriers.
Body cells will work the best if they have the correct:
- Temperature
- Water level
- Glucose concentration
Homeostatic control mechanisms
They are like the body’s smart thermostat as they help maintain balance and stability.
Homeostatic imbalance:
- Most diseases are as a result of homeostatic disturbance
- Age
The body’s control system becomes less efficient
Less stability in our internal environment
Mechanisms:
Variable: what is being controlled
Receptor: the sensor – it detects a change and send a signal
Control centre: receives the signal from the sensor and decides what to do from the signal
sent.
Effector: the component that makes changes based on the control centre’s decision.
, Your body will mostly use negative feedback mechanisms
- Aim to stop / reduce changes that end up going too far.
Positive feedback mechanisms
- Identify the change instead of stopping it.
Temperature regulation
Body temp. is regulated by a neg. feedback mechanism.
- If the temp rises, blood vessels will dilate meaning that more heat is lost from the
skin’s surface.
Sweating: when your body is hot, your sweat glands are stimulated in order to release
sweat.
- Liquid sweat will evaporate and turn into gas (it will evaporate due to the heat from
your skin)
- As your skin loses heat, it will cool down and produce less sweat.
Vasodilation: blood will carry most of the heat energy around your body.
- Capillaries that are underneath your skin can be filled with blood if you get too hot
- Brings blood closer to the surface of the skin (for more heat loss)
Vasoconstriction: opposite of vasodilation
- Capillaries underneath the skin get constricted
- Takes blood away from the skin’s surface so that heat can be lost
Piloerection: when the hairs on your skin stand up (shivering can also happen)
- The hairs will trap a layer of air next to the skin which is warmed by bodily heat.
- Air becomes an insulating layer
Homeostasis
The ability for the body to maintain a relatively stable internal condition
Dynamic state of equilibrium: when internal conditions may vary within relatively narrow
limits of one another
- Occurs despite the outside continuously changing
Every organ system will play a role in the maintenance of the constancy of the internal
environment
Homeostatic control: communication within the body that is essential to maintain
homeostasis (nervous or endocrine system)
- Communication is mainly accomplished by the nervous and endocrine systems as
they use electrical impulses / bloodborne hormones as information carriers.
Body cells will work the best if they have the correct:
- Temperature
- Water level
- Glucose concentration
Homeostatic control mechanisms
They are like the body’s smart thermostat as they help maintain balance and stability.
Homeostatic imbalance:
- Most diseases are as a result of homeostatic disturbance
- Age
The body’s control system becomes less efficient
Less stability in our internal environment
Mechanisms:
Variable: what is being controlled
Receptor: the sensor – it detects a change and send a signal
Control centre: receives the signal from the sensor and decides what to do from the signal
sent.
Effector: the component that makes changes based on the control centre’s decision.
, Your body will mostly use negative feedback mechanisms
- Aim to stop / reduce changes that end up going too far.
Positive feedback mechanisms
- Identify the change instead of stopping it.
Temperature regulation
Body temp. is regulated by a neg. feedback mechanism.
- If the temp rises, blood vessels will dilate meaning that more heat is lost from the
skin’s surface.
Sweating: when your body is hot, your sweat glands are stimulated in order to release
sweat.
- Liquid sweat will evaporate and turn into gas (it will evaporate due to the heat from
your skin)
- As your skin loses heat, it will cool down and produce less sweat.
Vasodilation: blood will carry most of the heat energy around your body.
- Capillaries that are underneath your skin can be filled with blood if you get too hot
- Brings blood closer to the surface of the skin (for more heat loss)
Vasoconstriction: opposite of vasodilation
- Capillaries underneath the skin get constricted
- Takes blood away from the skin’s surface so that heat can be lost
Piloerection: when the hairs on your skin stand up (shivering can also happen)
- The hairs will trap a layer of air next to the skin which is warmed by bodily heat.
- Air becomes an insulating layer
