Anatomy and Physiology Chapter 7
Put the following events associated with thyroid hormone production and release in the correct sequential order. Metabolism is regulated. Iodine is concentrated by the thyroid gland. Thyroxine and triiodothyronine are produced. Iodine is combined with the amino acid tyrosine.
2, 4, 3, 1
The pituitary hormone that controls the release of glucocorticoids from the adrenal cortex is
ACTH
The posterior pituitary gland secretes
ADH (vasopressin)
Which of the following adrenergic receptors increase cAMP levels?
B receptors
Insulin-like growth factors (IGFs) are intermediary hormones stimulated by which of the following hormones?
GH (growth hormone)
Which second messenger causes the release of calcium from the endoplasmic reticulum?
IP3
The pituitary hormone that controls hormone synthesis and release from the thyroid gland is
TSH
Hypothalamus
a brain region that contains several collections of neuronal cell bodies that provide a connection between the nervous system and the endocrine system
A friend of yours is working in a pharmaceutical development lab where they are working on a drug to cure Graves' disease. He poses the following four ideas listed below. Which would be the best solution?
a drug that breaks down the antibodies produced
When might negative feedback fail to regulate hormone production, and how would this affect hormone secretion?
a pathology in the endocrine gland could prevent negative feedback from working, resulting in hypersecretion
When stimulated by a particular hormone, there is a marked increase in the activity of G proteins in the membrane. The hormone is probably
a peptide
Which of the following is a specialized region of the circulatory system consisting of a capillary bed followed by a larger blood vessel followed by another capillary bed?
a portal system
When a catecholamine or peptide hormone binds to receptors on the surface of a cell,
a second messenger appears in the cytoplasm
A new hormone is discovered. Analysis suggests that it is synthesized on demand and has a long half-life in the bloodstream once it is released. It seems to activate gene transcription in its target cells though no cell surface receptors can be identified. Which type of hormone is this most likely to be?
a steroid
Anterior pituitary
a true endocrine gland of epithelial origin, sometimes called the adenohypophysis
Which is the correct order of events for hormones activating Gs proteins?
activation of G protein, binding of GTP, activation of adenylate cyclase, conversion of ATP to cAMP
What is the mechanism of action of lipid-soluble hormones?
activation of genes, which increases protein synthesis in the cell
After a lipid-soluble hormone is bound to its intracellular receptor, what does the hormone complex do?
acts as a transcription factor and binds to DNA, activating a gene
The ________ gland sits along the superior border of the kidney.
adrenal
Anterior pituitary hormone for adrenal gland
adrenocorticotrophic hormone (ACTH)
What tropic hormone stimulates cortisol from the adrenal gland?
adrenocorticotropic hormone (ACTH)
Match each hormone with its primary source. A. prolactin B. insulin C. aldosterone D. melatonin E. calcitonin F. epinephrine adrenal cortex
aldosterone
The adrenal cortex produces a steroid hormone called ________ that controls Na+ and K+ homeostasis and another steroid hormone called ________ that controls blood glucose levels.
aldosterone; cortisol
Match each term with the appropriate description. A. peptide hormone B. steroid hormone C. amino acid-derived hormone D. anterior pituitary E. hypothalamus F. posterior pituitary derivatives of tyrosine
amino acid-derived hormone
Posterior pituitary
an extension of the neural tissue of the brain, sometimes referred to as the neurohypophysis
Two hormones that have opposing effects are called
antagonists
Match each term with the appropriate description. A. peptide hormone B. steroid hormone C. amino acid-derived hormone D. anterior pituitary E. hypothalamus F. posterior pituitary true endocrine gland of epithelial origin
anterior pituitary
Which of the following statements regarding the anterior and posterior pituitary is correct?
anterior pituitary is composed of endocrine tissue while the posterior pituitary is composed of neural tissue
The amplification of the signal from a water-soluble hormone is achieved through an increase in
cAMP in the cytoplasm
When adenylyl cyclase is activated,
cAMP is formed
A cell's or tissue's response to a hormone primarily depends on the
cells receptors and the signal transduction pathway used by the cell
What keeps intracellular receptors from binding to DNA before a hormone binds to the receptor?
chaperone proteins
What is the function of the ventral hypothalamic neurons?
control secretion of thyroid stimulating hormone (TSH)
The outer layer of the adrenal gland is called the adrenal
cortex
Which of the following hormones has intracellular receptors?
cortisol
Patients that suffer from hyperinsulinemia may have a decreased number of insulin receptors on their cell membranes. This is an example of which phenomenon?
down-regulation
________ is a decrease in the number of receptors of target cells in order to dampen the effects of excess hormone.
down-regulation
Which is the most accurate example of a primary endocrine pathology in the pathway controlling cortisol secretion?
dysfunction in the adrenal cortex
Match each hormone with its primary source. A. prolactin B. insulin C. aldosterone D. melatonin E. calcitonin F. epinephrine adrenal medulla
epinephrine
Which hormone is classified as an amino acid derivative?
epinephrine
Hormones acting through signal transduction pathways elicit a ________ response compared to hormones that produce genomic effects.
faster
What does the word "exogenous" mean?
from outside the body
Typically, when steroid hormones bind to their receptors,
gene transcription may increase or decrease
Anterior pituitary hormone for muscles and bones
growth hormone (GH)
What distinguishes a hormone from other signaling molecules such as cytokines or paracrine or autocrine signaling molecules?
hormones are secreted into the bloodstream
How do endocrine hormones reach their target cells?
hormones are transported through the blood stream to target cells
Synergism occurs when
hormones working together produce a larger effect than predicted
The trophic hormones reach the pituitary through the
hypothalamic-hypophyseal portal system
Match each term with the appropriate description. A. peptide hormone B. steroid hormone C. amino acid-derived hormone D. anterior pituitary E. hypothalamus F. posterior pituitary site of vasopressin synthesis
hypothalamus
The hormones of the anterior pituitary are controlled by trophic hormones from the
hypothalamus
The most complex endocrine responses involve the
hypothalamus
Where is antidiuretic hormone (ADH), also known as vasopressin, synthesized?
hypothalamus
Which two organs of the body release hormones that lead to the release of thyroid hormone?
hypothalamus and anterior pituitary
Hyposecretion from damage to pituitary: hypothalamus: anterior pituitary: adrenal cortex:
hypothalamus: increased CRH secretion anterior pituitary: decreased ACTH secretion adrenal cortex: decreased cortisol secretion
Hypo secretion from atrophy of the adrenal cortex hypothalamus: anterior pituitary: adrenal cortex:
hypothalamus: increased CRH secretion anterior pituitary: increased ACTH secretion adrenal cortex: decreased cortisol secretion
Where are the neurohormones released by the posterior pituitary produced?
in the neuronal cell bodies found in the hypothalamus
If TRH levels increase, what will directly happen to the levels of TSH and thyroid hormone?
increase; increase
Match each hormone with its primary source. A. prolactin B. insulin C. aldosterone D. melatonin E. calcitonin F. epinephrine pancreas
insulin
After a hormone has exerted its effects, it typically
is inactivated or removed from the blood
Anterior pituitary hormone for ovary or testis
luteinizing hormone (LH); follicle stimulating hormone (FSH)
The inner portion of the adrenal gland is called the adrenal
medulla
Match each hormone with its primary source. A. prolactin B. insulin C. aldosterone D. melatonin E. calcitonin F. epinephrine pineal
melatonin
What is the most important regulatory factor controlling the circulating levels of thyroid hormone?
negative feedback
How would you classify the type of chemical released by the posterior pituitary (e.g., classic hormone, neurotransmitter, etc.)?
neurohormone
Which of the following hormones is regulated by a neuroendocrine ("letdown") reflex?
oxytocin
Which of the following is a neurohormone?
oxytocin
Hormones released by the posterior pituitary
oxytocin and vasopressin
Norepinephrine and epinephrine cause an increase in heart rate (HR) and stroke volume (SV), which is the amount of blood pumped out during each heartbeat. This effect is enhanced when thyroid hormone (TH) is also present. TH has little effect on HR and SV alone. What is the effect of TH on HR and SV called?
permissiveness
The signal molecule produced by one animal that may affect the behavior of another animal of the same species is the
pheromone
Cyclic AMP is degraded by __________
phosphodiesterase
Which intracellular substance degrades cAMP, thus inactivating the response to a hormone?
phosphodiesterase
What is the role of activated protein kinases?
phosphorylate proteins
Water-soluble hormones affect target cells by binding to __________.
plasma membrane receptors
Match each term with the appropriate description. A. peptide hormone B. steroid hormone C. amino acid-derived hormone D. anterior pituitary E. hypothalamus F. posterior pituitary storage and release site for oxytocin
posterior pituitary
________ pathologies arise in the last endocrine gland in a reflex.
primary
Anterior pituitary hormone for mammary glands
prolactin
Match each hormone with its primary source. A. prolactin B. insulin C. aldosterone D. melatonin E. calcitonin F. epinephrine anterior pituitary
prolactin
The pituitary hormone that stimulates milk production by the mammary glands is
prolactin
Hormones released by the anterior pituitary
prolactin, adrenocorticotropic hormone (ACTH), thyroid stimulating hormone (TSH), follicle stimulating hormone (FSH), growth hormone (GH), and luteinizing hormone (LH)
Order of release of hormone from the anterior pituitary
release of GnRH from hypothalamic neurons--> GnRH travels through portal system circulation--> stimulation of endocrine cells in anterior pituitary--> release of FSH--> FSH enters into general, systemic circulation--> FSH binds to ovary, promoting follicular growth and development and release of estrogen
In a simple endocrine reflex, the endocrine cell is the
sensor and integrating center
Steroid hormones are synthesized in the ________ of the cell.
smooth endoplasmic reticulum
Match each term with the appropriate description. A. peptide hormone B. steroid hormone C. amino acid-derived hormone D. anterior pituitary E. hypothalamus F. posterior pituitary cannot be stored in secretory vesicles
steroid hormone
Order of complex endocrine pathway
stimulus--> hypothalamus--> trophic hormone--> anterior pituitary--> trophic hormone--> endocrine gland--> hormone--> target tissue--> response
Hypophysectomized rats (those that have had their pituitary glands removed) grow fastest when given both GH and testosterone together than either separately. What is this phenomenon called?
synergism
A blood sample is found to have low levels of GHRH and excessive levels of GH and IGFs. Where would the pathology be located in this example?
the anterior pituitary
Which loss of function would occur if you were to sever the connection between the hypothalamus and the anterior pituitary?
the anterior pituitary would not release hormones in response to trophic hormone stimulation
In the simplest endocrine reflexes, which structure contains the sensor cells that trigger hormone release?
the endocrine gland
In the long loop negative feedback regulation of thyroid hormone (TH), where would TH have an inhibitory action?
the hypothalamus
What would the levels of TRH be in a person that has Graves' disease? Why?
the levels of TRH should be low because thyroid hormone is on a negative feedback loop
Mrs. Johnson goes to visit her doctor because of some health issues that she has been having, and one of the many tests that were run on Mrs. Johnson revealed that she had no circulating concentrations of vasopressin. The doctor does a further analysis of her hypothalamus and posterior pituitary to see what might be causing this problem. Predict which of the following might explain Mrs. Johnson's condition.
the neuronal cell bodies in the hypothalamus are damaged
What does the mRNA for a peptide hormone code for?
the preprohormone
Infundibulum
the stalk that connects the pituitary gland to the brain
Neurohormones are classified as such because __________.
they are produced by neurons
Which hormone's receptor is always bound to DNA, even when the receptor is empty?
thyroid hormone
Anterior pituitary hormone for thyroid gland
thyroid stimulating hormone (TSH)
What is the role of the hypothalamus with regard to hormone release and endocrine function?
to release trophic hormones that stimulate the anterior pituitary
The term for any hormone that controls the secretion of another hormone is a
trophic hormone
Growth factor hormones, such as insulin, bind to which type of receptor?
tyrosine kinase receptors
Which of the following are released by the posterior pituitary?
vasopressin, oxytocin
What type of hormones bind to receptors located on the cell membrane?
water-soluble hormones, such as insulin and epinephrine
