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