Homeostasis Flashcards
(11 cards)
what is the definition of homeostasis?
a living organism maintaining a stable internal environment
what observations can you take to measure homeostasis
- Core body temperature – TEMPERATURE
- Blood glucose levels – BLOOD GLUCOSE MONITORING
- Blood and tissue oxygen levels – OXYGEN SATURATIONS
- Blood pressure – BLOOD PRESSURE MONITORING
- Fluid and electrolyte balance – URINE OUTPUT/FLUID BALANCE
- Oxygen / Carbon dioxide/ pH – RESPIRATIONS PER MINUTE
- Cardiac output – PULSE RATE PER MINUTE
- Blood flow through peripheral tissues - CAPILLARY REFILL
what is the role of the control systems?
-the receptor/detector detects the problem
-the control centre recieves information from the receptor (sends to effector)
-the effector responds to the commands of the control centre by either opposing or enhancing stimulus
-this process maintains homeostasis
what are the different types of receptors/detectors?
chemicals- chemoreceptors
blood pressure- baroreceptors
temperature- thermoreceptors
pain- nociceptors
negative feedback mechanisms-
what happens when body temperature falls?
-blood vessels constrict so that heat is conserved
-sweat glands do not secrete fluid
-shivering(involuntary contraction of muscles) generates heat.
-heat is retained.
negative feedback mechanisms-
what happens when body temperature rises?
-blood vessels dilate, resulting in heat loss to the environment.
-sweat glands secrete fluid
-as the fluid evaporates, the heat is lost from the body.
- heat is lost to the environment
what is positive feedback mechanism?
positive feedback initiates stimuli and amplifies it (adds more), maintaining homeostasis.
what is negative feedback mechanism?
when a variable triggers a counteract response in order to come back to the set point. (maintains homeostasis)
example of positive feedback: a cut
- a break or tear in the blood vessel wall
- clotting occurs as platelets adhere to site and release chemicals
- released chemicals attract more platelets
- clotting proceeds until break is sealed by a newly formed clot (scabbing).
additional support to maintain homeostasis
-medication
- surgery
- respiratory support
- intravenous therapy
what is important in monitoring observations in practice
- a measure of homeostasis, ensures everything is stable
- essential for obs to be monitored and recorded accurately
- prioritise in workload planning
-provide full explanations to your patient and maintain privacy and dignity at all times
