Intro to Physiology Flashcards
Define the term ‘Human Physiology’
Human physiology is the normal functioning of the human body, and its integrative mechanisms that control them at the level of cells, tissue, organs, body systems and the whole body itself.
Define a ‘tissue’
A group of cells with similar structure and specialised function.
Define an ‘organ’
Composed of two or more primary tissues that function together to form a particular function.
Define a ‘body system’
A group of organs that perform related functions and work together to achieve a common goal.
Define ‘homeostasis’
Tendency of a biology system to maintain a state of equilibrium by resisting change.
Maintains a constant internal environment to allow cells to work efficiently and optimally within narrow limits, even when external conditions vary.
Utilises coordinated physiologically mechanisms.
What can disruption in homeostatic mechanisms result in?
Disease or death as this is caused by a deficient, inappropriate, or excessive homeostatic mechanisms.
What are the 3 components a physiological control system be comprised of?
Sensor- should be able to sense deviations from the normal in the internal environment that should be held within narrow limits.
Control Centre- integrate such information with other relevant information.
Effector- make appropriate adjustments to restore the controlled variable to the desired value.
What are the 2 classes of homeostatic control systems?
Intrinsic controls- local controls that are inherent in an organ.
Extrinsic controls- regulatory mechanisms initiated outside an organ; accomplished by the nervous or endocrine system.
What is a feedfoward control system?
Term used to describe responses made in anticipation of a change.
What is a feedback control system?
Response made after the change has been detected e.g. positive or negative.
Provide and explain an example of a positive and negative feedback system.
Positive feedback system- oxytocin at birth.
Negative feedback system- blood glucose levels.
What is important about negative feedback systems?
Negative feedback system promote stability by regulation of a controlled variable through the flow of information along a closed loop (oppose an initial change).
