Review: Homeostasis Slides Flashcards
What is homeostasis?
Maintenance of constant internal environment
What constitutes the internal environment?
Interstitial fluid that bathes every cell
What makes up organ systems?
Organs, which are groups of tissues working together, which are groups of cells
What do cells need to survive?
Energy (what drives the cell), food/nutrients, and oxygen
4 tissue types
Epithelial, Connective, Nervous, Muscle
Components of Homeostatic system
Receptors, Control Center/Integrator, Effectors
Receptor function
Provide information about specific conditions
Control center function
Evaluate info from receptors and know the set point (the norm)
Effector function
Respond to restore the deviation from the set values of the internal environment (respond to info from control center)
What is the receptor, control center, and effector in the temperature control scenario?
-Receptor: temperature monitoring nerve cells-Control center: hypothalamus-Effectors: skeletal muscles and blood vessels of skin
Temp change scenario: How do the effectors respond to a decrease in temperature?
Cause shivering (increases heat) and vasoconstriction (minimizes heat loss by thinning blood vessels so not as much water and therefore not as much heat get through)
What is a negative feedback mechanism?
The body does the opposite of what you’re faced with (brings variable back to “ideal” and reduce effect of stimulus)
What is a positive feedback mechanism (and two examples)?
Output enhances original stimulus (e.g., lactation, where suckling of baby triggers mechanism)
Endotherms
Regulate body temperature by generating metabolic heat and/or preventing heat loss (all mammals and birds)
Ectotherms
Depend on external heat sources to maintain body temperature
