Chapter 17. The Endocrine System
Which is one difference between the endocrine and the nervous system
The nervous system is more targeted in its response.
What is the fate of most hormones
They are degraded by the liver and kidneys
When peptides and catecholamines bind to the target cell, how do they stimulate its physiology
Through second messenger systems.
Which endocrine gland secretes several hormones that stimulate lymphatic organs and T cell activity
Thymus
Which endocrine gland serves as the site for lymphocyte maturation
Thymus
Which gland is located in the mediastinum superior to the heart
Thymus
Which gland is located immediately below the larynx and shaped like a butterfly
Thyroid gland
Once a steroid or thyroid hormone binds to its receptor, the receptor-hormone complex associates with a target gene and controls which of the following
Transcription
T/F: Andreal sex steroid have various developmental nad reproductive functions
True
Target cells can become more sensitive to a hormone by increasing the number of receptors via which process
Up-regulation
The adrenal cortex is composed of how many layers of tissue which differ in their distology and hormone output
3
What is a hypoglycemic hormone
A hormone that lowers blood glucose.
The pituitary gland is composed of two structures: the posterior lobe called the neurohypophysis and the anterior lobe called the ____.
Adenohypophysis.
What are the target cells of insulin
Adipose, skeletal muscle, and liver
Which secrete steroid hormones
Adrenal cortex, ovary, testes
Which adrenal cortical hormone helps maintain blood pressure and blood volume
Aldosterone
Peptide hormones are comprised of chains of what
Amino acids
What are monoamine hormones and neurotransmitters derived from
Amino acids; Monoamines are made from amino acids and retain an amino group, from which this hormone class gets its name.
In both sexes, the group of adrenal cortical hormones call ___ induce growth of pubic and axillary hair and their associated apocrine scent glands at puberty and stimulate the libido through adolescent and adult life.
Androgens
Which adrenal cortical hormones are responsible for the growth of pubic and axillary hair during puberty
Androgens
Where is the adrenal medulla
At the core of the adrenal gland, superior to the kidney
How are the endocrine and the nervous systems alike
Both use chemical messengers for communication
Parafollicular cells of the thyroid gland secrete ___ in response to rising blood calcium
Calcitonin
Which hormone stimulates the deposition of calcium in bones
Calcitonin
PTH is secreted in response to low levels of the mineral
Calcium
Thyroid hormone accelerates the breakdown of what
Carbs, fats and proteins
What is a potent glucocorticoid that stimulates fat and protein catabolism, gluconeogenesis, and the release of fatty acids into the blood
Cortisol
Which hormone is a potent glucocorticoid that is secreted in response to ACTH to help the body adapt to stress
Cortisol
Which hormones are classified as steroid hormones
Cortisol and testosterone (estrogens, progesterone, and testosterone; cortisol, aldosterone, and DHEA)
When they secretes hormones, the ovaries and testes are considered what type of glands
Endocrine
Which lands secrete their product by way of a duct directly onto an epithelial surface
Exocrine
T/F: Organs can have only endocrine or exocrine functions, not both.
False
T/F: The inner core of the adrenal gland is called the adrenal cortex.
False
Cells called spongiocytes are found within the zona ___ of the adrenal cortex.
Fasciculata
Cells called spongiocytes are found within the zona ____ of the adrenal cortex.
Fasciculata
The thyroid gland is composed of sacs that are filled with a protein-rich colloid. What are these sacs called
Follicles
What are the functions of testosterone
Fuel sex drive, develop male physique and reproductive system
Steroid hormones enter the target cell nucleus and act directly on the ____, changing target cell physiology by either activating or inhibiting transcription.
Genes. Some hormones enter the target-cell nucleus and act directly on the genes, changing target-cell physiology by either activating or inhibiting transcription of the gene for a metabolic enzyme or other protein. Such is the case with steroid hormones.
Mineralocorticoids are produced in the zona ___ of the adrenal cortex.
Glomerulosa
While both endocrine and nervous systems are involved with communication, they differ in their mechanisms. What is one difference between hormones of the endocrine system and neurotransmitters of the nervous system
Hormones are released into the interstitial fluids while neurotransmitters are released into the synaptic cleft.
Many of the functions of which organs are carried out by way of the pituitary gland, which is closely associated with it both anatomically and physiologically
Hypothalamus
Where are the paraventricular nucleus and supraoptic nucleus located
Hypothalamus
Peptides and catecholamines are hydrophilic and cannot penetrate a target cell. Thye therefore bind to receptors where
On the cell surface
What are the three types of interactive effects hormones can have
Permissive, synergistic, antagonistic
Which gland is thought to play a role in establishing 24-hour circadian rhythms
Pineal gland
Hypothalamic inhibiting hormones inhibit the release of hormones from the anterior ___ gland.
Pituitary
Which endocrine gland stores and releases oxytocin and antidiuretic hormone
Posterior pituitary
The pancreas is located retroperitoneally and ___.
Posterior to the stomach
In the ovary, the corpus luteum produces which hormone
Progesterone
What are the roles of estrogen and progesterone
Promote adolescent bone growth, regulate the menstrual cycle, contribute to the development of the reproductive system
Similar to neurotransmitters, hormones exert their action only on cells that have specific ____ that the hormones bind to.
Receptors
Endocrinology involves the study of cells that do which of the following
Secrete hormones
Through which process can one hormone molecule trigger the synthesis of a large number of enzyme molecules
Signal amplification
What type of hormone is synthesized from cholesterol and differ mainly in the functional groups attached to the four-ringed backbone
Steroid hormones
How do most steroids differ from one another
Steroid hormones are synthesized from cholesterol and differ mainly in the functional groups attached to the four-ringed steroid backbone.
Weak adrenal cortical androgens which possess little biological activity are converted to the much more potent androgen called ___
Testosterone
Weak adrenal cortical androgens which possess little biological activity are converted to the much more potent androgen called ___.
Testosterone
Weak adrenal; cortical androgens which possess little biological activity are converted to the much more potent androgen called ___.
Testosterone
Which hormone is responsible for the development and general health of the male reproductive tract
Testosterone
T/F Hormone transport proteins protect hormones from enzyme breakdown and from being excreted by the kidney.
True. Transport proteins not only carry the hydrophobic hormones, but also prolong their half-lives. They protect hormones from being broken down by enzymes in the blood plasma and liver and from being filtered out of the blood by the kidneys.
T/F: If excessive amounts of hormones are present they may bind to receptor sites for other related hormones and mimic their effects.
True. Two ways in which adverse side effects can arise are: (1) Excess hormones may bind to receptor sites for other related hormones and mimic their effects; and (2) a target cell may convert one hormone into another, such as testosterone to estrogen.
The gland that is the site of maturation for T lymphocytes is the _____
thymus
Through which of the following can cell-to-cell communication be accomplished
Paracrines, neurotransmitters, gap junctions, hormones
The ovoid glands partially embedded in the posterior surface of the thyroid are the ___ glands
Parathyroid
Which endocrine gland is housed in the sella turcica of the sphenoid bone
Pituitary gland
Which endocrine gland also acts as an exocrine gland
Pancreas
Where is the pineal gland
Inferior to the posterior portion of the corpus callosum
Pancreatic beta cells secrete ___ during and immediately following a meal.
Insulin
What is an example of a hypoglycemic hormone
Insulin
Endocrine secretions interact with their target cells and lead to which of the following
Intracellular changes
The nervous system is similar to the endocrine system in that both work through chemical messengers to affect physiological response. However, the nervous system has a ____ response.
Less persistent
The inner core of the adrenal gland is the adrenal ___.
Medulla
Which terms refers to the rate at which hormones are cleared from the blood
Metabolic clearance rate