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BIOL 252 EXAM 1 - HUMAN PHYSIOLOGY
UPDATED QUESTIONS AND 100% CORRECT
ANSWERS WITH A GUARANTEED A+|| 2025-2026
LATEST AND COMPLETE UPDATE WITH
VERIFIED SOLUTIONS|| GUARANTEED PASS!!
What is anatomy? - ANSWER: The study of the structure of living organisms.
What is physiology? - ANSWER: The study of how living organisms function.
What are some examples of physiological variation amongst individuals? -
ANSWER: Age, genetics, diet, weight, physical activity, and the environment.
What is homeostasis? - ANSWER: A relatively constant internal environment
What are some factors that must be maintained via homeostasis? - ANSWER:
Heart rate, body temperature, blood pressure, etc.
What are the components of homeostasis? - ANSWER: Receptors,
control/integrating center, and effectors.
What is a negative feedback mechanism? - ANSWER: A response that makes
deviation from the set point smaller--resisting change
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What is a positive feedback mechanism? - ANSWER: A response that increases
the deviation from the set point
Which mechanism is more common and why? - ANSWER: Negative feedback;
they bring us closer to homeostasis
When may a positive feedback mechanism be deplyed? - ANSWER: Childbirth,
opening of sodium channels with action potentials, or platelet-plug formation
during blood clotting.
What do receptors do in feedback loops? - ANSWER: Monitor the value of some
variable and send information to the control/integrating center.
What does the control/integrating center do in feedback loops? - ANSWER:
Establishes the set point and compares incoming information to that set point.
What does the effector do in feedback loops? - ANSWER: Take signals from the
control center and change activity to change the variable.
Why is there a limit to how large a cell can be? - ANSWER: They're limited by
the ratio of surface area to volume; Because smaller cells are more efficient; cell
volume increases exponentially
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What aspect of increasing a cell's size is the limiting factor? - ANSWER: Volume
What is the basic function of the plasma membrane? - ANSWER: Defines the
boundaries of the cell, controls cell interactions, and controls the movement of
materials in and out of the cell.
Why does the plasma membrane appear as a dark set of parallel lines under a
microscope? - ANSWER: The membrane is composed of a bilayer of
phospholipids with some intracellular fluid in the space between the layers.
What kind of lipids are found in the plasma membrane? - ANSWER:
Phospholipids, cholesterol, and glycolipids.
How much of the plasma membrane is made up by phospholipids? - ANSWER:
About 75%
How much of the plasma membrane is made up by cholesterol? - ANSWER:
About 20%
How much of the plasma membrane is made up by glycolipids? - ANSWER:
About 5%
BIOL 252 EXAM 1 - HUMAN PHYSIOLOGY
UPDATED QUESTIONS AND 100% CORRECT
ANSWERS WITH A GUARANTEED A+|| 2025-2026
LATEST AND COMPLETE UPDATE WITH
VERIFIED SOLUTIONS|| GUARANTEED PASS!!
What is anatomy? - ANSWER: The study of the structure of living organisms.
What is physiology? - ANSWER: The study of how living organisms function.
What are some examples of physiological variation amongst individuals? -
ANSWER: Age, genetics, diet, weight, physical activity, and the environment.
What is homeostasis? - ANSWER: A relatively constant internal environment
What are some factors that must be maintained via homeostasis? - ANSWER:
Heart rate, body temperature, blood pressure, etc.
What are the components of homeostasis? - ANSWER: Receptors,
control/integrating center, and effectors.
What is a negative feedback mechanism? - ANSWER: A response that makes
deviation from the set point smaller--resisting change
,2|Page
What is a positive feedback mechanism? - ANSWER: A response that increases
the deviation from the set point
Which mechanism is more common and why? - ANSWER: Negative feedback;
they bring us closer to homeostasis
When may a positive feedback mechanism be deplyed? - ANSWER: Childbirth,
opening of sodium channels with action potentials, or platelet-plug formation
during blood clotting.
What do receptors do in feedback loops? - ANSWER: Monitor the value of some
variable and send information to the control/integrating center.
What does the control/integrating center do in feedback loops? - ANSWER:
Establishes the set point and compares incoming information to that set point.
What does the effector do in feedback loops? - ANSWER: Take signals from the
control center and change activity to change the variable.
Why is there a limit to how large a cell can be? - ANSWER: They're limited by
the ratio of surface area to volume; Because smaller cells are more efficient; cell
volume increases exponentially
, 3|Page
What aspect of increasing a cell's size is the limiting factor? - ANSWER: Volume
What is the basic function of the plasma membrane? - ANSWER: Defines the
boundaries of the cell, controls cell interactions, and controls the movement of
materials in and out of the cell.
Why does the plasma membrane appear as a dark set of parallel lines under a
microscope? - ANSWER: The membrane is composed of a bilayer of
phospholipids with some intracellular fluid in the space between the layers.
What kind of lipids are found in the plasma membrane? - ANSWER:
Phospholipids, cholesterol, and glycolipids.
How much of the plasma membrane is made up by phospholipids? - ANSWER:
About 75%
How much of the plasma membrane is made up by cholesterol? - ANSWER:
About 20%
How much of the plasma membrane is made up by glycolipids? - ANSWER:
About 5%
