Final Exam Review: Unit 1

anatomy definition

the study of form

physiology definition

the study of function

levels of complexity and examples

chemical (Na, Cl)

cells (nerve, keratinocytes)- first level to contain life

tissues (blood, bone)

organ (heart, brain

organ system (integumentary, digestive)

organism

what is homeostasis

the ability to maintain a stable internal environment despite changing external conditions

what are the characteristics of homeostasis

variables fluctuate around set points (to reach dynamic equilibrium), as the boy responds to stressors. the goal is to reach balance. (set point = average set of values for any given variable)

what are the components of feedback loops (with examples)

receptors: monitor variables in body and send information to ICC (chemoreceptor and thermoreceptor)

Integrating control center: receives and processes information, determines and sends response to effectors (cardiac center of brain, endocrine system, hormones as communication molecules)

effectors: carry out corrective action (heart, uterus)

negative feedback loop definition 

mechanism for opposing and reversing change within the body. pushes variables closer to set point, and closer to equilibrium

positive feedback loop definition

mechanism that pushes the body away from homeostasis by reinforcing changes. pushes variables further outside of set point

what are the benefits and drawbacks of positive feedback loops

they allow the quick completion of stressful events, but they cause the body to be pushed further from the life sustaining state of homeostasis

what is an example of a positive feedback loop

the uterus contracts, the baby’s head hits the cervix and stretch receptors trigger the release of oxytocin, which causes the uterus to contract again

what is an example of a negative feedback loop

person rises from bed, blood pressure drops, baroreceptors sense change, the cardiac center releases norepinephrine to raise heart rate, the increased HR raises BP

what is a plane

an imaginary flat surface through the body or an organwh

what is the frontal plane

runs along the body’s length, dividing anterior and posterior

what is the sagittal plane

runs along the length of the body, separating left and right

• paramedian is a sagittal plane that divides unequally

• median plane is a sagittal plane that divides equally

what is the transverse plane

perpendicular to frontal and sagittal, divides the body into superior and anterior

• oblique is a transverse plane that divides the body at an angle