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GCU BIO202 EXAM 1 (ENDOCRINE AND
BLOOD) 2025 UPDATED ACTUAL EXAM WITH
CORRECT SOLUTIONS.
Hormones promote body homeostasis - correct answer-
Hormones react on each other and help keep homeostasis in
an organism. Hormones released from one gland can tell other
glands to make different hormones.
Endocrine system - correct answer- - Uses hormones - Affects
many organs - Slower and longer lasting
Nervous system - correct answer- - Uses electricity and
chemicals - Has a specific effector organ - Faster
Neurotransmitter - correct answer- A chemical compound
released by one neuron to affect the transmembrane potential
of another.
Hormone - correct answer- - A compound secreted by one cell
and travels through the bloodstream to affect cells elsewhere. -
Turns existing enzymes "on" or "off."
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Negative feedback - correct answer- - Responds to changed
body conditions - Signals the body to return to normal levels -
Once back to normal, turns off
Intercellular communication pathways - correct answer- Three
types: Direct communication, Paracrine, Endocrine
Direct communication - correct answer- Occurs between two of
the same type of cell
Paracrine communication - correct answer- Most common;
uses chemical signals to transfer information between cells
within a single tissue
Endocrine communication - correct answer- Slower; hormones
released into bloodstream and alter metabolic activities
Target organ - correct answer- Specific cells that have
receptors to "read" hormonal messages
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Lock and Key system - correct answer- Hormones fit receptors
on target cells like a key fits a lock
Hormone classification - correct answer- Three types: Amino
acid derivatives, Peptide hormones, Lipid derivatives (steroid
hormones)
Free hormones - correct answer- Function for less than 1 hour;
diffuse out of bloodstream; broken down by enzymes or
absorbed by liver/kidney
Protein-bound hormones - correct answer- Remain in
circulation longer; enter bloodstream attached to proteins
Lipid-soluble hormone - correct answer- Enters cell, binds to
intracellular receptor, activates gene transcription, and directs
protein synthesis
Lipid-insoluble hormone - correct answer- Uses first and
second messengers (e.g., cAMP) to relay signal; doesn't enter
the cell directly
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Amplification - correct answer- A small number of hormones
trigger thousands of second messengers, magnifying the effect
on target cells
Down regulation - correct answer- High hormone levels reduce
receptor numbers; decreases sensitivity (e.g., type 2 diabetes)
Up regulation - correct answer- Low hormone levels increase
receptor numbers; increases sensitivity
Hormones promote body homeostasis - correct answer-
Hormones react on each other and help keep homeostasis in
an organism. Hormones released from one gland can tell other
glands to make different hormones.
Endocrine system - correct answer- - Uses hormones - Affects
many organs - Slower and longer lasting
Nervous system - correct answer- - Uses electricity and
chemicals - Has a specific effector organ - Faster
GCU BIO202 EXAM 1 (ENDOCRINE AND
BLOOD) 2025 UPDATED ACTUAL EXAM WITH
CORRECT SOLUTIONS.
Hormones promote body homeostasis - correct answer-
Hormones react on each other and help keep homeostasis in
an organism. Hormones released from one gland can tell other
glands to make different hormones.
Endocrine system - correct answer- - Uses hormones - Affects
many organs - Slower and longer lasting
Nervous system - correct answer- - Uses electricity and
chemicals - Has a specific effector organ - Faster
Neurotransmitter - correct answer- A chemical compound
released by one neuron to affect the transmembrane potential
of another.
Hormone - correct answer- - A compound secreted by one cell
and travels through the bloodstream to affect cells elsewhere. -
Turns existing enzymes "on" or "off."
,2 | Page
Negative feedback - correct answer- - Responds to changed
body conditions - Signals the body to return to normal levels -
Once back to normal, turns off
Intercellular communication pathways - correct answer- Three
types: Direct communication, Paracrine, Endocrine
Direct communication - correct answer- Occurs between two of
the same type of cell
Paracrine communication - correct answer- Most common;
uses chemical signals to transfer information between cells
within a single tissue
Endocrine communication - correct answer- Slower; hormones
released into bloodstream and alter metabolic activities
Target organ - correct answer- Specific cells that have
receptors to "read" hormonal messages
,3 | Page
Lock and Key system - correct answer- Hormones fit receptors
on target cells like a key fits a lock
Hormone classification - correct answer- Three types: Amino
acid derivatives, Peptide hormones, Lipid derivatives (steroid
hormones)
Free hormones - correct answer- Function for less than 1 hour;
diffuse out of bloodstream; broken down by enzymes or
absorbed by liver/kidney
Protein-bound hormones - correct answer- Remain in
circulation longer; enter bloodstream attached to proteins
Lipid-soluble hormone - correct answer- Enters cell, binds to
intracellular receptor, activates gene transcription, and directs
protein synthesis
Lipid-insoluble hormone - correct answer- Uses first and
second messengers (e.g., cAMP) to relay signal; doesn't enter
the cell directly
, 4 | Page
Amplification - correct answer- A small number of hormones
trigger thousands of second messengers, magnifying the effect
on target cells
Down regulation - correct answer- High hormone levels reduce
receptor numbers; decreases sensitivity (e.g., type 2 diabetes)
Up regulation - correct answer- Low hormone levels increase
receptor numbers; increases sensitivity
Hormones promote body homeostasis - correct answer-
Hormones react on each other and help keep homeostasis in
an organism. Hormones released from one gland can tell other
glands to make different hormones.
Endocrine system - correct answer- - Uses hormones - Affects
many organs - Slower and longer lasting
Nervous system - correct answer- - Uses electricity and
chemicals - Has a specific effector organ - Faster
