AND SOLUTIONS SCORED A+
✔✔Variable - ✔✔Homeostasis control mechanism being regulated. Ex: body
temperature, heart rate, blood pressure, oxygen content of blood, blood sugar, etc.
✔✔Receptor - ✔✔First component: some type of sensor that monitors the environment
and responds to changes called stimuli, by sending information (input) to the control
center.
✔✔Control center - ✔✔Second component: receives information (input) from the
receptor along the afferent pathway. Determines the set point, which is the level or
range at which a variable is to be maintained.
✔✔Effector - ✔✔Third component: receives information (output) from the control center
along the efferent pathway. Provides the means for the control centers response
(output) to the stimulus.
✔✔Afferent pathway - ✔✔Approaches the control center (monitors)
✔✔Efferent pathway - ✔✔Exits the control center (issues orders to muscles or glands)
✔✔Negative feedback mechanisms - ✔✔The output shuts off the original effect of the
stimulus or reduces its intensity. Causes the variable to change in a direction opposite
to that of the initial change, returning to its ideal value. If too fast, then slows. If hot, then
cools.
✔✔Body temperature and blood sugar are regulated by what? - ✔✔Negative feedback
mechanism
✔✔some variables regulated by negative feedback mechanisms to maintain
homeostasis - ✔✔core body temperature, blood glucose, plasma calcium, amount of
oxygen and carbon dioxide in blood, blood pressure, volume of body water
✔✔Main goal for negative feedback mechanisms? - ✔✔To prevent sudden severe
changes within the body.
✔✔Positive feedback mechanisms - ✔✔The result or response enhances the original
stimulus so that the response is accelerated. The change that results proceeds in the
same direction as the initial change, causing the variable to deviate further and further
from its original value or range.
, ✔✔Positive feedback mechanisms control... - ✔✔Infrequent events that do not require
continuous adjustments. Often referred to as cascades. Ex: labor contractions and
blood clotting.
✔✔Homeostatic imbalance - ✔✔Disturbance in homeostasis. Occurs when the usual
negative feedback mechanisms are overwhelmed and destructive positive feedback
mechanisms take over.
✔✔Anatomical position - ✔✔Standard anatomical reference point, the body is erect with
feet slightly apart. It resembles "standing at attention", except the palms face forward
and the thumbs point away from the body.
✔✔Directional terms - ✔✔Explains where one body structure is in relation to another.
✔✔superior (cranial) - ✔✔toward the head end or upper part of a structure or the body;
above
✔✔inferior (caudal) - ✔✔away from the head end or toward the lower part of a structure
or the body; below
✔✔anterior (ventral) - ✔✔toward or at the front end of the body; in front of
✔✔posterior (dorsal) - ✔✔toward or at the back end of the body; behind
✔✔medial - ✔✔toward or at the midline of the body; on the inner side of
✔✔lateral - ✔✔away from the midline of the body; on the outer side of
✔✔intermediate - ✔✔between a more medial and a more lateral structure
✔✔proximal - ✔✔closer to the origin of the body part or the point of attachment of a limb
to the body trunk
✔✔distal - ✔✔farther from the origin of a body part or the point of attachment of a limb
to the body trunk
✔✔superficial (external) - ✔✔toward or at the body surface
✔✔deep (internal) - ✔✔away from the body surface; more internal
✔✔Axial - ✔✔Makes up the main axis of our body. Includes head, neck, and trunk.
✔✔Two fundamental divisions of the body - ✔✔Axial and appendicular