PHGY 216 Module 1 Exam – Complete
Study Guide with Practice Questions &
Detailed Answers|| LATEST UPDATE 2026
What are the functions of the endocrine system? -CORRECTANSWER - maintain
constant internal environment via regulation of metabolism and H2O/electrolyte balance
- adaptive stress response
- growth and development
- reproduction
- red blood cell production
- integrating with the ANS in regulating both the circulation and digestive functions
What are hormones? -CORRECTANSWER hormones are chemical substances that
are secreted directly into the blood at low quantities and exert a physiological effect at a
distant target tissue
What are characteristics of hydrophilic hormones? -CORRECTANSWER - water loving
- highly water soluble and have low lipid solubility
- found unbound to carrier molecules within the plasma
- most are peptides or proteins
- amines are hormones based on single amino acid residues
,What are examples of amine hormones? -CORRECTANSWER - catecholamines
(norepinephrine and epinephrine)
- catecholamines are found free and bound to carrier molecules
- thyroid hormones
- thyroid hormones are not hydrophilic
How are peptide hormones synthesized? -CORRECTANSWER synthesized and
secreted by the same cellular machinery that makes proteins within cells
How are peptide hormones synthesized in the synthesis phase? -CORRECTANSWER
large precursor proteins called preprohormones are synthesized by ER ribosomes into
prohormones
How are peptide hormones synthesized in the packaging phase? -CORRECTANSWER
as they travel through the ER and Golgi complex, these prohormones are processed
into active hormones and packaged into secretory vesicles
How are peptide hormones synthesized in the storage phase? -CORRECTANSWER
these hormone containing secretory vesicles can be stored until the cell receives the
appropriate signal
,How are peptide hormones synthesized in the secretion phase? -CORRECTANSWER
the appropriate signal initiates exocytosis if the vesicles and the hormones are released
into the blood
What are characteristics of lipophilic hormones? -CORRECTANSWER - lipid loving
- highly soluble in lipids and poorly soluble in water
- require a carrier molecule for transport throughout the body
What are examples of lipophilic hormones? -CORRECTANSWER - amine thyroid
hormone
- steroid hormones
How are steroid hormones synthesized ? -CORRECTANSWER - all synthesized from
cholesterol
- which steroid hormone is produced by a particular tissue depends on the specific
enzymes within the cells of that tissue
- not stored
- they are secreted as they are synthesized
- to regulate the amount of steroid hormone released, you need to regulate its synthesis
Where is cortisol made? -CORRECTANSWER adrenal cortex
, Which hormones are dissolved in plasma? -CORRECTANSWER peptide hormones are
able to freely dissolve in plasma
Which hormones are found bound to carrier molecules or proteins? -
CORRECTANSWER steroid and thyroid hormones bind to specific carrier molecules or
to plasma proteins such as albumin
Which hormones are dissolved in plasma or bound to carrier molecules or proteins? -
CORRECTANSWER catecholamines are unique as 50% are found free in the plasma
and 50% bind to albumin, they are water soluble
How do hormones interact with their target cells? -CORRECTANSWER - only free,
unbound hormones can interact with a receptor at its target cell
- not an issue for hydrophilic hormones and catecholamines
What is the dynamic equilibrium of lipophilic hormones binding to its carrier? -
CORRECTANSWER - at a given time, not 100% of a steroid hormone in the blood is
bound to its carrier molecule
- instead, the hormones are dynamically unbinding and rebinding which results in a
small fraction of hormone that is unbound at any given time
- this unbound hormone is active and able to act on target cells
Study Guide with Practice Questions &
Detailed Answers|| LATEST UPDATE 2026
What are the functions of the endocrine system? -CORRECTANSWER - maintain
constant internal environment via regulation of metabolism and H2O/electrolyte balance
- adaptive stress response
- growth and development
- reproduction
- red blood cell production
- integrating with the ANS in regulating both the circulation and digestive functions
What are hormones? -CORRECTANSWER hormones are chemical substances that
are secreted directly into the blood at low quantities and exert a physiological effect at a
distant target tissue
What are characteristics of hydrophilic hormones? -CORRECTANSWER - water loving
- highly water soluble and have low lipid solubility
- found unbound to carrier molecules within the plasma
- most are peptides or proteins
- amines are hormones based on single amino acid residues
,What are examples of amine hormones? -CORRECTANSWER - catecholamines
(norepinephrine and epinephrine)
- catecholamines are found free and bound to carrier molecules
- thyroid hormones
- thyroid hormones are not hydrophilic
How are peptide hormones synthesized? -CORRECTANSWER synthesized and
secreted by the same cellular machinery that makes proteins within cells
How are peptide hormones synthesized in the synthesis phase? -CORRECTANSWER
large precursor proteins called preprohormones are synthesized by ER ribosomes into
prohormones
How are peptide hormones synthesized in the packaging phase? -CORRECTANSWER
as they travel through the ER and Golgi complex, these prohormones are processed
into active hormones and packaged into secretory vesicles
How are peptide hormones synthesized in the storage phase? -CORRECTANSWER
these hormone containing secretory vesicles can be stored until the cell receives the
appropriate signal
,How are peptide hormones synthesized in the secretion phase? -CORRECTANSWER
the appropriate signal initiates exocytosis if the vesicles and the hormones are released
into the blood
What are characteristics of lipophilic hormones? -CORRECTANSWER - lipid loving
- highly soluble in lipids and poorly soluble in water
- require a carrier molecule for transport throughout the body
What are examples of lipophilic hormones? -CORRECTANSWER - amine thyroid
hormone
- steroid hormones
How are steroid hormones synthesized ? -CORRECTANSWER - all synthesized from
cholesterol
- which steroid hormone is produced by a particular tissue depends on the specific
enzymes within the cells of that tissue
- not stored
- they are secreted as they are synthesized
- to regulate the amount of steroid hormone released, you need to regulate its synthesis
Where is cortisol made? -CORRECTANSWER adrenal cortex
, Which hormones are dissolved in plasma? -CORRECTANSWER peptide hormones are
able to freely dissolve in plasma
Which hormones are found bound to carrier molecules or proteins? -
CORRECTANSWER steroid and thyroid hormones bind to specific carrier molecules or
to plasma proteins such as albumin
Which hormones are dissolved in plasma or bound to carrier molecules or proteins? -
CORRECTANSWER catecholamines are unique as 50% are found free in the plasma
and 50% bind to albumin, they are water soluble
How do hormones interact with their target cells? -CORRECTANSWER - only free,
unbound hormones can interact with a receptor at its target cell
- not an issue for hydrophilic hormones and catecholamines
What is the dynamic equilibrium of lipophilic hormones binding to its carrier? -
CORRECTANSWER - at a given time, not 100% of a steroid hormone in the blood is
bound to its carrier molecule
- instead, the hormones are dynamically unbinding and rebinding which results in a
small fraction of hormone that is unbound at any given time
- this unbound hormone is active and able to act on target cells
