Homeostasis Flashcards
(45 cards)
What are tissues?
Groups of cells that share the same characteristics or specializations
What are organs?
Collection of tissues, usually of several different type, that synchronise to perform a particular function
What do all cells require in order to survive?
Energy
Preventing disturbance to the system is maintaining what?
Homeostasis
What is physiology?
The study of the body working in harmony
What is pathology?
The study of the body not working in harmony - i.e when something goes wrong
What systems co-ordinate and control all other systems in the body?
Nervous and endocrine
Maintaining optimum internal environment within the body for all cells to function is known as what?
Homeostasis
Failure to regulate changes to our bodies internal environment results in what?
Disturbance to the system pathology
The body usually has a range within which it can tolerate change… true or false?
True
What are some common everyday changes to our internal environment?
External temperature, diet, exercise
At extremes of variables what happens to homeostasis?
It is disturbed/ it becomes less effective
Through what control system is the basis of homeostasis usually controlled by?
Negative feedback
The magnitude of the generated response in negative feedback is in proportion to what?
The magnitude of the generated signal and the magnitude of the difference from the normal
What is the aim of negative feedback?
To restore the internal environment to optimal conditions
What picks up the stimulus to change?
Receptor
What are homeotherms?
Us
What is a characteristic of negative feedback?
it restores the regulated varibale AFTER ir initial displacement but cannot PREVENT it from happening
Are feed forward systems, more of less sophisticated than negative feedback?
More sophisticated
Why are feed forward systems more sophisticated?
because to some extent they can predict and even prevent change
In feed forward what permits the system to anticipate change?
Additional receptors
What is positive feedback the opposite to?
Negative feedback
What do positive feedback cycles lead to?
Instability in the system/ opposite to negative feedback which aims to restore the system
Give an example of a positive feedback system in physiology?
Action potential - Na+ influx leads to a higher permeability to Na+
