1: introduction to physiology and homeostasis Flashcards
mechanistic theory of physiology
answers the “how” questions in physiology
teleological approach to physiology
answers the “why” questions of physiology
muscle tissue
consists of cells specialized for contracting
nervous tissue
consists of cells specialized for initiating and transmitting electrical impulses
epithelial tissue
consists of cells specialized for exchanging materials between the cell and its environment
exocrine glands
secrete through ducts to the outside of the body
endocrine glands
lack ducts and release their products into the blood
connective tissue
distinguished by having relatively few cells with an abundance of extra cellular matrix. this tissue supports and anchors various body parts.
homeostasis
maintenance of a relatively stable internal environment
intercellular fluid
fluid contained within the body’s cells
extracellular fluid
the internal environment of the body. made up of plasma and interstitial fluid.
homeostatically regulated factors (7)
concentration of nutrients
concentration of O2 and CO2
concentration of waste
pH
concentrations of water/salt/electrolytes
volume and pressure
temperature
the circulatory system
transports materials like nutrients, O2 and CO2
the digestive system
breaks down food into molecules that can be absorbed into the plasma for distribution to the body cells
the respiratory system
gets O2 and eliminates CO2 to the external environments
the urinary system
removes excess water, salt, acid, and other electrolytes from the plasma and eliminates them in the urine
the skeletal system
provides support and protection for the soft tissues and organs
the muscular system
moves the bones to which the skeletal muscles are attached
the integumentary system
serves as an outer protective barrier that prevents internal fluid from being lost and foreign microorganisms from entering
the immune system
defends against foreign invaders
the nervous system
controls and coordinates body activities and detects changes in the external environment
the endocrine system
all hormone secreting glands, regulatory
the reproductive system
not essential for homeostasis
negative feedback
a change in homeostatically controlled factor triggers a response that seeks to restore the factor to normal by moving the factor in the opposite direction of its initial change
positive feedback
the output enhances or amplifies a change so that the controlled variable continues to move in the direction of the initial change
