Homeostasis Flashcards
What are the three components of any homeostatic mechanism?
Receptors, A Control Centre and Effectors
What do receptors respond to?
Stimuli bringing change to a controlled condition within the body
Where do receptors send information to in a homeostatic mechanism?
A Control Centre
Homeostasis aims to do what?
Maintain a relatively stable internal environment
Internal environment typically refers to what?
The composition of the interstitial fluid (from textbook)
What are the controlled conditions that homeostasis regulates?
Body temperature, water balance, electrolyte balance, blood pH (acidity), blood glucose level and blood pressure
What are the two types of Homeostatic feedback loops?
Negative and Positive feedback loops
Baroreceptors respond to what?
Changes in blood pressure
Where can baroreceptors be found?
The aortic arch and carotid sinus
Chemoreceptors respond to what?
Changes in chemical stimuli including Oxygen, Carbon Dioxide, and Glucose
What are chemoreceptors that specifically respond to blood glucose concentration? Where can they be found?
Glucoreceptors, found in the pancreas and hypothalamus
Osmoreceptors respond to what?
Changes in fluid balance and blood osmolarity
Where can osmoreceptors be found?
The Hypothalamus
Thermoreceptors respond to what?
Changes in temperature
Where can thermoreceptors be found?
On the skin and mucous membranes (Peripheral) and deeper in the body (Central)
Where do homeostatic control centres get their input from?
Receptors sending information about changes in controlled conditions
What do homeostatic control centres do after receiving information (input) from receptors?
Analyse the input and determine an appropriate response to carry out via effectors (output)
What are effectors?
Means by which the body’s control centres can affect and change controlled conditions.
Typically, effectors in the body are either ___ or ___
Typically, effectors in the body are either Glands or Muscles
What do homeostatic negative feedback mechanisms aim to achieve in relation to a change in a controlled condition?
Homeostatic negative feedback mechanisms aim to reverse the change in the controlled condition
e.g. Decrease body temperature if the body is overheating
What do homeostatic positive feedback mechanisms aim to achieve in relation to a change in a controlled condition?
Homeostatic positive feedback mechanisms aim to increase or intensify the change in the controlled condition until the end result is reached and the loop is terminated.
e.g. The loop of the baby exerting pressure on the cervix causing uterine contractions, pushing the baby towards the cervix during labor
