Intro to Physiology, Homeostasis, and Feedback Flashcards
What is the study of body structures called?
Anatomy
What is the study of function called?
Physiology
What is the study of how physiological processes are altered in disease or injury called?
Pathophysiology
What does ‘Structure Determines Function’ mean?
The form (anatomy) of a body part dictates what it does (physiology)
What are two types of regulation to maintain homeostasis?
Intrinsic Regulation and Extrinsic Regulation
Who coined the term “homeostasis”?
Walter Cannon
Define Homeostasis
The maintenance of a stable internal environment. It is the ability to detect change, activate mechanisms that oppose it, and thereby maintain relatively stable internal conditions. It is also described as a state of equilibrium where opposing forces are in balance.
What is extrinsic regulation?
Organ systems working together to regulate organism homeostasis; a coordinate response.
What is intrinsic regulation?
Local, automatic adjustments of cells, tissues, and organs to an environmental change.
Give an example of extrinsic regulation.
Increasing heart rate and respiration rate during exercise to increase oxygen supply and remove CO2.
Give an example of intrinsic regulation.
When cells are starved of oxygen, they release chemical signals that cause blood vessels to dilate, allowing blood flow to that area.
What are the three components of a regulatory mechanism (extrinsic regulation)?
Receptor (sensor), Control Center (Integrator), and Effector (Response).
What is the role of a receptor in regulation?
To respond to stimuli (change in the environment) and send signals to the control center.
What is the role of the control center in regulation?
To analyze information and determine the appropriate response.
What is the role of positive feedback?
To increase (amplify) the original stimulus to speed up the body’s response.
What is the role of the effector in regulation?
To carry out instructions and provide a means for response.
Give an example of positive feedback loop in normal physiology.
Labor and Delivery
What is the role of negative feedback?
The response of the effector shuts off (negates) the original stimulus, or reduces its intensity once balance (homeostasis) in the body is reached.
Give an example of positive feedback in blood clotting.
Damaged cells release chemicals, which accelerate the clotting process.
How much of the body is composed of water?
Approximately 60%
What is extracellular fluid (ECF)?
Fluid outside of the cells. It contains about 1/3rd of total body water (TBW). It is comprised of interstitial fluid and intravascular fluid (plasma).
What is the baroreceptor reflex?
The body’s way of adjusting blood pressure to a homeostatic range when it gets too high/low.
What are baroreceptors?
Receptors that monitor blood pressure in the blood vessels by the amount of stretch in them.
What are vasomotor centers?
They regulate blood pressure by adjusting blood vessel diameters.
