A&P - Chapter 2 Flashcards
(27 cards)
What does survival depend on?
Depends on the maintenance or restoration of homeostasis
Homeostasis
Relative constancy/stability of the internal environment
- a set point / range
What are 5 examples of things that need to be in homeostasis?
- Temperature
- CO2
- O2
- Blood glucose
- pH
Feedback loops
Is the part of a system in which some portion (or all) of the system’s output is used as input for future operations
What are 2 types of feedback loops?
- Positive feedback
2. Negative feedback
Positive feedback
Is when there is an increase of change or output that results in an amplification
Negative feedback
Is where there is a decrease of change or output that results in a decrease of function
What is an example of positive feedback? (2)
- Child birth
- contracting - Blood clotting
What are 2 example of negative feedback?
- Thermoregulation
- if you get too hot or too cold the body will bring it back to normal - Blood sugar regulation
- insulin lowers blood sugar when it is too high
What does feedback mean?
Sending back information
What are the 4 basic components of feedback loops?
- Sensor mechanism
- Integrator or control centre
- Effector mechanism
- Feedback
Sensor mechanism
Senses a change
Integrator or control centre
Analyzes information and send out instructions to deal with the change
Effector mechanism
Responds to instructions
Feedback mechanism
Detects a degree of change
Afferent
Conducting inward or toward something
- sensor –> integrator/control centre
Efferent
Conducting outward or away from something
- integrator/control centre –> effector
What comes first, afferent or efferent?
Afferent
- A comes before E on the alphabet
What are 4 things negative feedback loops do?
- They inhibit
- They stabilize physiological variables
- They produce an action that is opposite to the change that activated the system
- They are responsible for maintaining homeostasis
What are 3 things positive feedback loops do?
- They stimulate
- They amplify the original stimulus
- They feedback to control centre promotes further change in the direction of the original deviation/stimulus
Which feedback loop is more common?
Negative feedback loops
What are positive feedbacks most useful in?
When we want to amplify something in order to complete them quickly
What do all organs function to?
Maintain homeostasis
What are body functions related to?
Age
