Homeostais Flashcards
anatomy
the study of structure
physiology
the study of body functions
pathophysiology
- the study of disordered body function, disease
- the basis for clinical medicine
- abnormal functioning of the body associated with disease
homeostasis
-the relative stable conditions inside the body needed for survival
chemical level
- various atoms and molecules make up the body
- smallest building blocks of matter
- oxygen, carbon, nitrogen and hydrogen make up 96% of body
- combination of atoms make molecules (proteins, carbohydrates, fats and nucleic acids
cellular level
- fundamental of structure and function of a living being
- smallest unit capable of carrying out the process associated with life
cell functions
- obtaining O2 and nutrients
- performing energy-generating chemical reactions
- eliminating wastes
- synthesizing proteins and other cell components
- moving materials throughout the cell
- responding to the environment
- reproducing
tissues level
-cells of similar structure and specialized function combine to form tissues
four primary tissues
muscle, nervous, epithelial and connective
tissue: muscle
- cells for contracting
- generates tension
- produces movement
- skeletal: moves the skeleton
- cardiac: pumps blood out of the heart
- smooth: controls the movement through hollow tubes
tissue: nervous
- initiating and transmitting electrical impulses
- signals that relay information from one part of the body to another
tissue: epithelial
- specialized cells for exchanging materials between the cell and the cell environment
- epithelial sheets and secretory glands
types of epithelial
simple: one layer
stratified: more than one layer
shape: squamous, cuboidal, columnar
exceptions to epithelial
-pseudostratified: one layer that looks like multiple layers due to the cells different sizes with one nuclei
PSCCE: pseudostratified ciliated columnar epithelial
-in the trachea
transitional: changes shape
ex. bladder, cuboidal is empty, squamous is full
tissue: connective
- connects, supports and anchors various body parts
- areolar (most common), loose and dense
- tendons, blood, bone
fluid compartments
- most body cells are not in direct contact with the external environment
- cell survival depends on maintaining a relatively stable internal fluid environment
organ level
-two or more types of primary tissue organized to perform a function
body system
- groups of organs
- each system perform a related function
- 11 organ systems
intracellular fluid (ICF)
-fluid collectively contained within all body cells
extracellular fluid (ECF)
- fluid outside the cell
- internal environment of the body
- contains the interstitial fluid and plasma
plasma
fluid portion of the blood
interstitial fluid
- surrounds and baths the cells
- in between two cells
factors maintained homeostatically
- concentration of nutrients, O2, CO2, waste products
- pH
- concentrations on water, salt, and other electrolytes
- volume and pressure (BP)
- temperature
homeostatic control system
- functionally interconnected network of body components that operates to maintained a given factor constant
- detects deviations from normal
- integrate this info with other info
- make adjustments to restore the factor to normal
intrinsic control system
- local
- controls that are built into an organ
- an exercising muscle requires more O2 and the blood vessels will dilate to deli ever more O2 to that muscle
extrinsic control system
- systemic
- controls are initiated outside an organ to alter the organs activity
- permits coordinated regulation of several organs towards a common goal
- accomplished by the nervous and endocrine system
feedback control
- promotes stability
- anticipates change
- promotes a change in one direction
- with instability, disease can happen
negative feedback
- both intrinsic and extrinsic control systems
- a change in the controlled variable triggers a response that dives the variable in the opposite direction of initial change
- will go back to baseline
positive feedback
- amplifies the initial change
- moves system away from the set point
- important during childbirth (oxytocin), breast milk production, blood clotting
positive feedback loop
- cell depolarization
- increase cell Na+ permeability
- increase Na influx
- decrease cell membrane potential
- back to an increase in cell Na+ permeability
disruptions in homeostasis
when a disruption becomes so severe that it no longer compatible with survival, death results
components in a negative feedback system
- deviation in a controlled variable
- detected by a sensor
- informs the integrator
- sends instructions to the effector
- brings about compensatory response
