Exam 5 Practice Quiz Flashcards
A hormone is defined as a chemical substance produced by an endocrine cell in response to certain stimuli to cause an effect on a target cell, which in turn causes a change or adjustment in various organ systems in the body.
true
The endocrine system has little to do with homeostasis for processes involved in growth and development, blood pressure, or regulation of ions.
false
There are 4 endocrine signaling pathways that exist. In telecrine signaling, a hormone:
a. Exerts an effect by diffusing to a nearby cell
b. Exerts an effect on the same cell that secreted it
c. Exerts an effect over a long distance via the bloodstream
c
Hormones can be classified according to structure and are synthesized from different parent compounds. Amines are specifically derived from the amino acid:
a. Threonine
b. Tryptophan
c. Tyrosine
d. Phenylalanine
c
For peptide hormones, the structure is usually very similar across species
true
Within a species, peptide hormones have very similar structures and may only differ in a side chain, thus allowing them to weakly act on several types of receptors.
true
For a peptide hormone to be synthesized, the mRNA is translated on ribosomes to form a:
a. Pre-Pro-hormone
b. Pre-hormone
c. Pro-hormone
d. Hormone
a
For steroid, amine and eicosanoid hormones, secretion from a cell is:
a. Fast and occurs through secretory vesicles
b. Fast and occurs through simple transfer through the cell membrane
c. Slow and occurs through secretory vesicles
B
Examples of amine hormones include:
a. Catecholamines, dopamine, and growth hormone
b. Oxytocin, dopamine, and growth hormone
c. Catecholamines, dopamine, and thyroid hormones
d. Oxytocin, dopamine, and prostaglandin
C
Feedback loops can be long, short or ultra-short. An example of a long feedback loop would be feedback from target tissue back to the pituitary/hypothalamus.
t
When a hormone interacts with its target cell, there are several factors that determine the level of response achieved in the target tissue. One of these factors would be number and/or affinity of receptors for that hormone.
t
If less hormone can achieve 50% of the maximal response, then it can be said that sensitivity has:
a. Increased
b. Decreased
c. Stayed the same
A
In up-regulation of a hormone, the number or affinity of receptors increases. Therefore, it can be said that sensitivity of the hormone has:
a. Increased
b. Decreased
c. Stayed the same
A
There are several ways in which a hormone-receptor complex can generate a response in the target cell. In a classic cell membrane receptor system:
a. The response is typically rapid and uses an enzyme system with kinases
b. The response is typically slow and uses an enzyme system with kinases
c. The response is typically rapid and uses a second messenger system
C
Second messenger systems may be coupled to G-proteins and may use the adenylyl cyclase-cAMP system.
t
An example of a hormone response that uses cAMP as its second messenger system is:
a. Thyrotropin-releasing hormone (TRH)
b. Thyroid-stimulating hormone (TSH)
c. Oxytocin
d. Growth-hormone releasing hormone (GHRH)
B
An example of a catalytic hormone receptor system is:
a. Tyrosine kinase
b. Phospholipase C
c. Phospholipase E
A
Insulin and insulin-like-growth-factors (IGF) use this type of tyrosine kinase system:
a. Tyrosine-kinase associated receptor
b. Monomer-type
c. Dimer-type
C
Steroid hormones use intracellular receptor systems and must find their receptor in the cytoplasm or nucleus. Additionally, they must bind:
a. Steroid-binding element (SBE)
b. Steroid-responsive element (SRE)
c. Steroid-like element (SLE)
B
The anterior and posterior lobes of the pituitary gland are derived from different tissue and are functionally different.
t
Examples of neurotransmitters that influence the hypothalamus include dopamine, serotonin and GABA.
t
Control of the adenohypophysis and neurohypophysis occurs via the hypothalamus. For the adenohypophysis, hormones are produced in the hypothalamus, travel down axons, and are released at the end of the neurons.
There are several releasing-hormones produced by the hypothalamus that in turn, cause release of hormones from the anterior lobe of the pituitary. Name 3 of these hormones.
- THYROTROPIN RELEASING HORMONE (TRH)
- CORTICOTROPIN RELEASING HORMONE (CRH)
- GONADOTROPIN RELEASING HORMONE (GnRH)
In response to pulsatile secretions of releasing-hormones from the hypothalamus, these types of cells in the anterior pituitary secrete hormones episodically:
a. Trophic
b. Autocrine
c. Paracrine
d. Pars
A
Name three hormones released by the anterior pituitary.
- GROWTH HORMONE (GH)
- ADENOCROTICOTROPIC HORMONES (ACTH)
- PROLACTIN
Two stimulators of TSH secretion include:
a. Increase in triiodothyronine (T3) and thyroxine (T4)
b. Somatostatin and growth hormone
c. TRH and a decrease in T3
C
ACTH is secreted as a large pre-pro-hormone called:
a. POMC
b. Β-lipotropin
c. Β-endorphin
A
An inhibitor of ACTH secretion can be:
a. A decrease in cortisol
b. Stress
c. TRH
d. ACTH
A
Secretion of FSH and LH are stimulated by:
a. Melatonin
b. Prolactin
c. Pheromones
d. Testosterone
D
A tonic inhibitor of prolactin is:
a. Suckling
b. Dopamine
c. TRH
B
GH secretion peaks:
a. Nocturnally
b. Diurnally
A
The following two factors will stimulate release of GH:
a. Increased glucose, GH
b. Increased FFA, somatostatin
c. Decreased glucose, increased amino acids (AA)
C
Somatomedins are produced in the liver and an example is:
a. Ketones
b. Insulin-like growth factor 1 (IGF-1)
c. Leptin
B
The direct anabolic effects of growth hormone are mediated by somatomedins
t
In addition to the anabolic effects of GH, it also has catabolic effects. An example of a catabolic effect of GH is:
a. Increased lipolysis and release of free fatty acids (FFA)
b. Decreased gluconeogenesis
c. Increased glucose uptake in muscle
d. Increased protein synthesis in muscle
A
Dwarfism can be due to lack of GH.
t
Oxytocin is primarily produced in this portion of the hypothalamus:
a. Supraoptic nuclei
b. Paraventricular nuclei
c. Preoptic nuclei
d. Medial nuclei
B
Hormones produced by the hypothalamus are synthesized as pre-pro-hormones, packaged into vesicles as pro-hormones, and this compound is cleaved off as it travels down the axon to the posterior pituitary:
a. Synaptophysin
b. Pantophysin
c. Nanophysin
d. Neurophysin
D
Oxytocin not only has effects in the female, but also has effects in the male on sperm movement and ejaculation.
t
A stimulator of anti-diuretic hormone (ADH) secretion is:
a. Increased blood pressure
b. Decreased plasma osmolality
c. Increased plasma osmolality
d. Increased blood volume
C
ADH has effects on both the kidney and vascular smooth muscle. In the kidney, ADH will:
a. Cause Na+ reabsorption
b. Decrease water reabsorption
c. Allow expression of aquaporin proteins in the distal convoluted tubules and collecting ducts for reabsorption of water
C
ADH causes dilation in vascular smooth muscle.
The predominant hormone secreted by the follicles of the thyroid gland is:
a. Reverse T3
b. Triiodothyronine (T3)
c. Thyroxine (T4)
C
In the synthesis of thyroid hormones, a tyrosine amino acid attaches to this structure within the follicular cell:
a. Iodine
b. Thyroglobulin
c. Peroxidase
B
How is iodine transported into the follicular cell of the thyroid?
a. Symport
b. Antiport
c. Na+/K+ ATPase
A
Which hormone causes release of thyroid hormones from the thyroid gland?
a. TRH
b. T3
c. T4
d. TSH
D
When a follicular cell is stimulated to release thyroid hormones (T3, T4), these hormones are cleaved from what compound?
a. Monoiodotyrosine
b. Diiodotyrosine
c. Thyroglobulin
d. Peroxidase
C
The biologically active form of thyroid hormone is:
a. T3
b. T4
c. rT3
A