Homeostasis - 4% Flashcards
What is Homeostasis?
Homeostasis is the ability of the body to maintain a relatively stable internal environment when faced with a continually changing external environment.
What are the three components of a control system?
- RECEPTOR
- CONTROL CENTRE
- EFFECTOR
Whats the core body temperature?
37°C
What are three examples of homeostasis?
- Regulation of blood sugar
- Fluid balance
- Thermoregulation
What is Thermoregulation?
The regulation of body temperature.
What is the Hypothalamus and where can it be found?
The hypothalamus is the control centre for temperature regulation and is found in the brain, above the pituitary gland to which it is attached.
What are the four mechanisms of heat transfer?
Radiation - infra red waves (thermal energy) at rest 50-60% body heat loss.
Conduction - heat transfer between objects that are in direct contact (molecule to molecule contact).
Convection - movement in fluids. Normally enhances heat exchange from the body surface to the air.
Evaporation - heat absorbed from the body causes water molecules to change from a liquid to a gas.
What is Advection Heat Transfer?
A forced convection that differs from convection as the movement of heat is confined to the horizontal plane.
This type of heat transfer requires an outside force, such as wind, fan or movement to displace air.
What are two heat loss mechanisms the body has?
- Vasodilation of cutaneous blood vessels - skin blood vessels swell (more heat to the shell)
- Enhanced sweating - when the body becomes overheated or when the environmental temperature is > 610°C heat cannot be lost by other means then sweating becomes necessary.
What is Hypothermia?
A condition in which core temperature drops below the required temperature for normal metabolism and body functions (35.0 °C)
What is Hyperthermia?
Is defined as a temperature greater than 37.5–38.3°C
