BIO 253 Exam 1 115 Questions and Answers (A+ Solution
guide)
Explain how anatomy and physiology are related
.......ANSWER......anatomy is the study of structure of body parts
and physiology is the study of function of body parts. they are
closely related because the function of a body part is associated
to where it is located
levels of organization (smallest to largest) .......ANSWER......atom
molecule
macromolecule
organelle
cell
tissue
organ
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organ system
organism
Homeostasis .......ANSWER......maintenance of a stable internal
environment
Homeostatic mechanism .......ANSWER......self-regulating systems
that monitor aspects of the internal environment and correct them
as needed
3 PARTS
1. receptor
2. control center
3. effector
Receptor .......ANSWER......detects and provides information
about the stimuli
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Control center .......ANSWER......decision-maker that maintains the
set point
Effector .......ANSWER......muscle or gland that responds to the
control center, and causes the necessary change in the internal
environment
Negative feedback .......ANSWER......effectors reduce or oppose
the change in internal conditions (stop the change or reverse the
change)
examples: controlling body temperature, blood pressure, and
glucose level in the blood
Positive feedback .......ANSWER......effectors increase change,
instead of reversing it (leads to unstable conditions that will
eventually bring it back to homeostasis)
examples: blood clotting, and the uterine contractions of
childbirth
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2 Main Portions of the Human Body .......ANSWER......axial
portion: head, neck, and trunk
appendicular portion: upper and lower limbs
Major Body Cavities .......ANSWER......cranial cavity : houses brain
vertebral canal (spinal cavity) : contains spinal cord
thoracic cavity : houses lungs and thoracic viscera
abdominopelvic cavity : contains abdominal and pelvic
Organ systems .......ANSWER......integumentary
skeletal
muscular
nervous
endocrine cardiovascular
lymphatic
respiratory