Item 9 Flashcards
REad Endocrine overview: 6th edition: Ch.5: 124-134, 137-145 (5th edition: Ch. 5: 125-133, 136-144)
Hypothalamus and pituitary: 6th edition: Ch 6: 148 153, Ch 19: 541 543, Ch 22: 661 663 , Ch 21: 619 623 (5th edition: Ch6: 149 153 , Ch 19: 541 543, Ch 22: 662 663 , Ch 21: 619-623)
ok
35
32
= 67
Cell-to-cell communication that is direct involves small ions and small molecules that use _ _ via connexons
gap junctions
Cell-to-cell communication that is indirect via chemical messenger involves a secretorycell sending a chemical messenger that reaches the receptor of a target cell. The target cell’s receptor needs to be present as well as be _ to the messenger
specific
growth factors, clotting factors and cytokines are examples of _ chemical messenger signaling
paracrine
Paracrines diffuse a _ distance through extracellular fluid, from a secretory cell and binds to adjacent cells
short
Neurotransmitters are released from neurons at synapses, which are specifically labelled as _ and _ cells
presynaptic and postsynaptic
Can neurotransmitters be sent far distances?
yes, provided the axon is super-long
Hormone signalling involves a secretory cell or _ cell which uses a hormone that is a chemical cellular that is released into _ fluid into the blood stream though gaps in capillaries.
endocrine;
interstitial/extracellular
Hormone signalling uses _ capillaries to travel into the blood
fenestrated
Do hormones use receptors?
yes, otherwise they do not respond to hormones
T or F: Hormones are released into the bloodstream and can reach both near and far targets
true
Neurohormones secrete from neurons, and they are released from the ending of the neuron into the blood and will only act on cells with _
receptors to the particular neurohormone
Krinein means to _ or _
secrete or separate
The endocrine system secretes hormones into the bloodstream and have …
target cells which express receptors for the hormone, responsible for hormone function
The organs that secrete hormones are:
- glands
- cells embedded in _
tissue
Primary endocrine glands are meant to…
secrete hormones
Secondary endocrine organs are meant to…
have a main function, but can also release hormones
Primary endocrine organs include:
glands:
- pineal
- hypothalamus
- pituitary
- thyroid
- parathyroid
- thymus
- _ gland
- pancreas
- ovaries (placenta) / testes
adrenal gland
Secondary endocrine organs include:
- heart
- stomach
- liver
- kidney
- small intestine
- _
skin
Functions of the endocrine system:
metabolism
growth and development
reproduction
…
water and electrolyte balance
digestive and circulatory systems - regulation
responses to stress
Regulation of hormone secretion (stimulate or inhibit):
1. neurotransmitters - interaction with _ system
2. other hormones
3. metabolites - glucose (high - insulin), amino acids (insulin, glucagon)
4. ions (potassium, calcium, etc.)
5. …
hormonal feedback - regulation of the actual hormone being secreted - keeps homeostasis in check
Type I diabetes means that, without insulin, the child cannot…
absorb nutrients
Disorders with _ hormone predict an incredibly small or an incredibly large size
growth
Classification of hormones:
_ hormones, which are water soluble (can dissolve in plasma)
hydrophilic
Hydrophilic are lipophobic, and cannot…
cross plasma membranes
Peptide and protein hormones and catecholamines (adrenaline, etc.) are examples of _ hormones
hydrophilic (cannot cross the plasma membrane)
Steroid and thyroid hormones are _ hormones, readily crossing the plasma membrane (lipophilic)
hydrophobic
Hydrophilic hormones are secreted by _, moving into the blood vessel and are dissolved by messengers
exocytosis
Hydrophobic hormones are secreted by _, and are transported in the blood by carrier proteins, although less than 1% can be ‘free’ or without a carrier protein
diffusion
Two types of hormone receptors are _ and membrane-bound
intracellular
Intracellular receptors bind with hydro_ hormones, which are considered cytoplasmic/cytosolic or nuclear receptors
hydrophobic
Intracellulr receptors directly alter gene transcription, and are _ responses
slower
Membrane-bound receptors include G-protein linked receptors, and ligand-gated ion channels, and bind hydro_ hormones.
hydrophilic
Membrane-bound receptors offer _ responses to hormone signals
rapid
What makes a cell responsive to a particular hormone?
a. the chemical properties of the hormone
b. the presence of a receptor for that particular hormone
c. the site where the hormone is secreted
d. the location of the target cells in the body
b. the presence of a receptor for that particular hormone
Hydrophobic hormones require a hydrophobic messenger that diffuses across the plasma membrane into the target cell, where is can then bind to a cytoplasmic receptor, or move into the nucleus, forming with a _ receptor.
Cytoplasmic receptors and the hydrophobic messenger can join, creating hormone-receptor complex that allows them to…
enter the nucleus through a nuclear pore
The hormone-receptor complex forms with the DNA, creating a hormone _ _ (HRE), enabling a subset of genes that would be activated when this binds
hormone receptor element
If the hormone-receptor complex binds to DNA, it binds as a HRE, which activates the transcription of that particular gene, producing _, which leaves the nucleus and binds to ribosomes where the message is translated into proteins which cause a biological effect
mRNA (messenger RNA); the messenger part of it creates proteins made in the cell
The creation of _ into ion channels, enzymes, created structures for the cell, etc. are instigated by the mRNA, a reaction from the hormone-receptor complex binding to DNA as a hormone response element (HRE), a process of hydrophobic hormones
proteins
Hydrophilic hormones use membrane-bound receptors, specifically - linked receptors
G-protein
G-protein linked receptors can act on _ _ or alter enzyme activity e.g., cAMP second messenger system
ion channels
G-protein linked receptors are associated with _, which is a G protein that has an alpha, beta, and gamma component
GDP
When the G protein is BOUND, it includes alpha, beta and gamma subunit proteins that are connected to GDP
unbound
when the messenger binds to the receptor, the G-protein complex will be UN/BOUND
unbound/separation
GDP is BOUND/RELEASED, and GTP is BOUND/RELEASED when a hydrophilic messenger activates a membrane-bound receptor
released;
bound
When a hydrophilic hormone activates a membrane-bound receptor, its result could be the GTP bind to an alpha subunit protein, activating …, which requires no further energy
an ion channel
When a hydrophilic hormone activates a membrane-bound receptor, its result could be the GTP bind to an alpha subunit protein, which can move to an enzyme, i.e., _ _
adenylate cyclase
When a hydrophilic hormone activates a membrane-bound receptor, its result could be the GTP bind to an alpha subunit protein, which can move to an enzyme, i.e., adenylate cyclase.
The activation of adenylate cyclase thereby catalyses the conversion of _ to cAMP, a second messenger, which binds to another protein in the cell
ATP
When a hydrophilic hormone activates a membrane-bound receptor, its result could be the GTP bind to an alpha subunit protein, which can move to an enzyme, i.e., adenylate cyclase.
The activation of adenylate cyclase thereby catalyzes the conversion of ATP to cAMP, a second messenger, which binds to another protein in the cell, protein _ _, and activates it.
kinase A
When a hydrophilic hormone activates a membrane-bound receptor, its result could be the GTP bind to an alpha subunit protein, which can move to an enzyme, i.e., adenylate cyclase.
The activation of adenylate cyclase thereby catalyzes the conversion of ATP to cAMP, a second messenger, which binds to another protein in the cell, protein kinase A, and activates it.
This causes protein kinase A, an enzyme, that phosphorylates a subset of proteins in the cell, i.e., …
change the activity of those proteins, altering the activity of the cell, creating a biological response in the cell
When a hydrophilic hormone activates a membrane-bound receptor, its result could be the GTP bind to an alpha subunit protein, which can move to an enzyme, i.e., adenylate cyclase.
The activation of adenylate cyclase thereby catalyzes the conversion of ATP to cAMP, a second messenger, which binds to another protein in the cell, protein kinase A, and activates it.
This causes protein kinase A, an enzyme, that phosphorylates a subset of proteins in the cell, by the use of _, creating Protein-P + ADP, creating a response in the cell
ATP
One purpose of cAMP as a second messenger in hydrophilic hormones is creating a…
greater biological response in the cell or amplification
Put the following steps in the cAMP second messenger pathway in the correct order:
- G-protein is activated
- hormone binds to receptor located in plasma membrane
- cellular proteins are phosphorylated
- protein kinase A is activated
- cAMP is synthesized
- activity of adenylate cyclase increases
- hormone binds to receptor located in plasma membrane
- G-protein is activated
- activity of adenylate cyclase increases
- cAMP is synthesized
- protein kinase A is activated
- cellular proteins are phosphorylated
Hormones simply relay info to cells through receptors, but do not themselves…
carry out a target effect
Receptor response is dependent on receptor shape and quantity, which can be _
dynamic
Hormonal responses vary depending on strength and _ of stimuli
type
Cell-cell communication in the endocrine system:
- endocrine cells _ and release a hormone
synthesize
Cell-cell communication in the endocrine system:
- endocrine cells synthesize and release a hormone
- determined by _ nature of hormone
chemical
Cell-cell communication in the endocrine system:
- endocrine cells synthesize and release a hormone
- determined by chemical nature of hormone
- determined by chemical nature of hormone and _ of receptor
availability
Cell-cell communication in the endocrine system:
- endocrine cells synthesize and release a hormone
- determined by chemical nature of hormone
- determined by chemical nature of hormone and availability of receptor
- this can be impacted by response-specific _of information transfer
termination
Cell-cell communication in the endocrine system:
- endocrine cells synthesize and release a hormone
- determined by chemical nature of hormone
- determined by chemical nature of hormone and availability of receptor
- this can be impacted by response-specific termination of information transfer - signal _
amplification
Cell-cell communication in the endocrine system:
- endocrine cells synthesize and release a hormone
- determined by chemical nature of hormone
- determined by chemical nature of hormone and availability of receptor
- this can be impacted by response-specific termination of information transfer - signal amplification
- hormone and target cell-specific _
response
Hormones are _ messengers that produce responses in target cells by binding to specific receptors
chemical
Different hormones have different chemical characteristics, i.e., hydro_ or _
philic or phobic
T or F: cells can have receptors for more than one hormone
true
There is more than one type of receptor for a given hormone. This results in the activation of different…
intracellular signalling pathways
The pituitary gland is composed of the anterior (front) and posterior (back) pituitary, attached to the hypothalamus by the _
infundibulum
Neurosecretory cells project into _ pituitary, release hormones into bloodstream
posterior
Nucleus in neurons, means …of neurons
cluster of cell bodies of neurons
Cluster of neurons in _ nucleus secrete oxytocin, whereas the _ nucleus secrete antidiuretic hormone
supraoptic - oxy
paraventricular - ADH
Both supraoptic and paraventricular nuclei have long _ which project to the posterior pituitary gland
axons
- they are neurosecretory cells!
A capillary bed in the posterior pituitary enables blood flow which hormones are secreted from the endings of _ cells into the blood stream that’s bound, and leaves through blood vessels
neurosecretory - supraoptic or paraventricular nuclei
ADH or _ is a posterior pituitary gland hormone
vasopressin
Vasopressin/ADH’s primary function is to increase _ reabsorption in the kidneys
water
ADH/vasopressin conserves body water, maintain water balance and fluid homeostasis and INCREASES…
blood volume and blood pressure
By regulating permeability of cells in the kidney and increasing its permeability, means ADH/vasopressin increases reabsorption and LOWERS/RAISES urine output
lowers
Filtrates flows through collecting duct, forming _
urine
ADH acts on cells in the COLLECTING DUCTS to insert _ transport molecules into the cells that line the kidneys, increasing water reabsorption back into the blood
aquaporin
What regulates ADH secretion?
- low blood pressure
- low blood volume
- …
- high plasma osmolarity
Changes in _ are detected by receptors in the hypothalamus, which is the most potent stimulus for ADH release
osmolarity (osmoreceptors)
Blood pressure changes are detected by baroreceptors which INCREASED/REDUCED stretch in:
- walls of the atria of the heart
- aortic and carotid arteries
REDUCED
- if pressure is reduced, then it means there isn’t enough volume in the blood, needing an increase in blood volume
People who consume alcohol need to urinate more because they are not…
getting effective water reabsorption due to alcohol’s block of ADH
Oxytocin-secreting endocrine cells in the _ release hormone from the posterior pituitary
hypothalamus
Oxytocin stimulates contraction of the _ muscle, which is the most common pharmacological agent to induce labour
uterine
Oxytocin is important for ejection of milk after parturition or _, secreted in response to suckling, causes smooth muscle contraction for milk ejection in breast tissue
labour
Milk ejection in breast tissue is caused by _ muscle contraction
smooth
Cervical stretch from the baby dropping lower in the uterus to initiate labour stimulates _ release, which causes uterine contractions and pushes baby against the cervix causing more cervical stretch, a type of positive feedback loop.
oxytocin
What stops the uterine contractions is…
the delivery of a baby
The _ pituitary is considered the hypothalamic-pituitary portal system
anterior
Median eminence in the infundibulum is the site of hormone release for the _ pituitary, travelling to a second capillary bed there
anterior
Hypothalamic hermones will bind to _ cells in the anterior pituitary, with hormones inhibiting or stimulating release of another hormone from _ [first word]
endocrine;
the endocrine cell
Prolactin-inhibiting hormone is a.k.a. _
dopamine
Thyrotropin-releasing hormone (TRH)
TRH
Corticotropic-releasing hormone
CRH
growth hormone-releasing hormone
GHRH
Growth hormone-inhibiting hormone (GHIH), a.k.a.,
somatostatin
gonadotropin-releasing hormone
GnRH
T or F: Prolactin-INHIBITING hormone (PIH) has not been found in research.
false; PRH hasn’t been found in nature
TSH
thyroid stimulating hormone
ACTH
adreno-corticotropic hormone
lh
luteinizing
Follicle-stimulating hormone
FSH
GH
growth hormone
T or F: anterior pituitary tropic hormones travel through the bloodstream, and only act on receptors of their target organs
true
Anterior pituitary hormone, PIH (prolactin-inhibiting hormone)/dopamine is released in the hypothalamic-pituitary portal vein, which then _ the anterior pituitary gland to release prolactin which are later responsive to the breasts, creating milk ejection
INHIBITS - it prevents the release of prolactin from happening
The two inhibiting hormones from the anterior pituitary system are:
- prolactin-inhibiting hormone (PIH) / dopamine
… / somatostatin
growth hormone-inhibiting hormone
PIH/dopamine prevents _ from being released to the breasts, whereas GHIH/somatostatin prevents _ from being released to the liver and/or other cells throughout the body
prolactin;
growth hormone
Of the 7 (or 6, if you don’t include PRH) hormones released by the anterior pituitary system, 2 are inhibiting hormones and 5 are _
activating
Of the 7 (or 6, if you don’t include PRH) hormones released by the anterior pituitary system, 2 are inhibiting hormones and 5 are activating. The 5 include:
- TRH – > TSH -> thyroid gland - TH
- CRH –> ACTH -> adrenal cortex - cortisol
- GHRH –> GH -> liver/cells throughout body - insulin-like growth factors
- PRH –> prolactin -> breasts
- …? –> luteinizing hormone or follicle-stimulating hormone -> gonads -> androgens (male) or estrogen or progesterone (female)
GnRH
T or F: the breasts and other cells throughout the body do not produce hormones, whereas other target organs stimulated by the anterior pituitary system do release hormones
true
Hormones in the anterior pituitary system use _ feedback, whether as a short loop (from anterior pituitary to the hypothalamus preventing build up of anterior pituitary hormone), or a long loop (endocrine gland to the hypothalamus which suppresses both the hypothalamic and the pituitary hormone)
negative; that’s why inhibiting or releasing hormones exist. the hormone inhibits or releases hormone which prevents build up
1st level - hypothalamus
2nd level - anterior pituitary
3rd level - endocrine gland
4th level - target cell (which responds, but doesn’t release a hormone)
Feedback of _ inhibits release of CRH and ACTH by actions at the hypothalamus and anterior pituitary, respectively
cortisol
Humans have _ growth spurts, with girls before boys for the pubertal growth spurt
2 - the other is postnatal (up until 2)
Factors influencing growth:
- diet - adequate nutrition, energy, calcium, protein
- genetics
- growth factors
- PROLONGED stress (emotional or physical)
- hormones:
–growth hormone
– _ hormone
– sex hormones: androgens and estrogens
– insulin
thyroid
Growth hormone pathway:
1. hypothalamus releases GHRH or ghih (_)
somatostatin
Growth hormone pathway:
1. hypothalamus releases GHRH or ghih (somatostatin)
2. anterior pituitary releases or inhibits _ (respectively)
GH
Growth hormone pathway:
1. hypothalamus releases GHRH or GHIH (somatostatin)
2. anterior pituitary releases or inhibits growth hormone (GH) (respectively)
3. If released, GH is sent in _ to the liver and/or cells throughout the body, with more released during the DAY/NIGHT
pulses;
night
Growth hormone pathway:
1. hypothalamus releases GHRH or GHIH (somatostatin)
2. anterior pituitary releases or inhibits growth hormone (GH) (respectively)
3. If released, GH is sent in pulses to the liver and/or cells throughout the body, with more released during the night
4. If sent to the _, it would then release its own insulin-like growth factors would be released
liver
_, exercise and acute stress stimulate growth hormone
sleep!
The release of … creates a negative feedback loop for the anterior pituitary and the hypothalamus, ensuring sufficient amounts of growth hormone and/or GHRH or GHIH are released, respectively
insulin-like growth factors
The release of growth hormone creates a _ feedback loop for the hypothalamus, ensuring sufficient amounts of GHRH and/or GHIH (somatostatin) are released. This can be confusing, since GH would ensure LESS/MORE release of GHIH, preventing further release of growth hormone by the anterior pituitary. But, it is still considered a _ feedback loop
negative;
MORE;
negative
Actions of GH/insulin-like growth factors:
- promotor linear growth
- _ actions supporting growth (increase available energy for use)
metabolic
GH/insulin-like growth factors promote LINEAR growth in two ways:
1. increases cell proliferation (cell number)
2. increases cell size by _ _
protein synthesis
GH/insulin-like growth factors promote LINEAR growth in two ways:
1. increases cell proliferation (cell number)
2. increases cell size by _ _
protein synthesis
GH/insulin-like growth factors use metabolic actions supporting growth by increasing the available …?
energy for use
GH/insulin-like growth factors use metabolic actions supporting growth by increasing the available energy for use. This is done in 4 ways:
1. INHIBIT/STIMULATE glucose uptake into adipose tissue and skeletal muscle
inhibit - leaves more in the system for later use?
GH/insulin-like growth factors use metabolic actions supporting growth by increasing the available energy for use. This is done in 4 ways:
1. INHIBIT glucose uptake into adipose tissue and skeletal muscle
2. INHIBIT/STIMULATE lipolysis (fat breakdown) in adipose tissue)
stimulate - the increased fat breakdown means more energy is available in tissue, rather than left for storage
GH/insulin-like growth factors use metabolic actions supporting growth by increasing the available energy for use. This is done in 4 ways:
1. INHIBIT glucose uptake into adipose tissue and skeletal muscle
2. STIMULATE lipolysis (fat breakdown) in adipose tissue)
3. INHIBIT/STIMULATE gluconeogenesis in liver
stimulate - you want more glucose released from the liver to allow greater amount of energy available, when needed
GH/insulin-like growth factors use metabolic actions supporting growth by increasing the available energy for use. This is done in 4 ways:
1. INHIBIT glucose uptake into adipose tissue and skeletal muscle
2. STIMULATE lipolysis (fat breakdown) in adipose tissue)
3. STIMULATE gluconeogenesis in liver
4. DECREASE/INCREASE uptake of amino acids into cells
INCREASE - we want more amino acids into the cells to encourage the amount of available energy for use
GH/insulin-like growth factors use metabolic actions supporting growth by increasing the available energy for use. This is done in 4 ways:
1. INHIBIT glucose uptake into adipose tissue and skeletal muscle
2. STIMULATE lipolysis (fat breakdown) in adipose tissue)
3. STIMULATE gluconeogenesis in liver
4. DECREASE/INCREASE uptake of amino acids into cells
INCREASE - we want more amino acids into the cells to encourage the amount of available energy for use to build proteins
increasing uptake of amino acids into cells by GH and insulin-like growth factors helps to…
have available components for building proteins
T or F: the liver only does insulin-like growth factor secretion
false - many tissues do (not adipose tissue or muscle)
T or F: Protein synthesis increase only occurs in non-adipose tissue,
true
Adipose tissue and muscle both are targets of GH by acting to … However, they increase lipolysis and increase amino acid uptake, respectively, which the latter does not
decrease glucose uptake
Growth of long bones involves the _ plate, whether in the leg or arm
epiphyseal
The area that growth of long bones occurs is in the _ _
epiphyseal plate, not in the shaft or epiphysis
The epiphyseal plate is the site of growth for increases in length of bone, and is composed of _
cartilage
T or F: blood vessels are not found in bone
false - they are
Bone marrow’s cavity contains: red and _ marrow
yellow
_ marrow in long bones produces red and white blood cells, whereas _ marrow in long bones produce adipocytes
red;
yellow
The epiphyseal plates in children are more _ than in adults
separated, composed as cartilage
_ _ closure occurs during late puberty
epiphyseal plate (long bones)
Epiphyseal plate closure is affected by circulating _ hormones
sex
Epiphyseal plate closure means that no further… once complete
increase in bone length happens
The epiphyseal plate separates the epiphysis from the bone _ of a long bone
shaft
Cells that make up new bone in the epiphyseal plate are _
chondrocytes
If we look at the epiphyseal plate vertically and imagine bone at the top, going down we anticipate:
1. bone
2. epiphyseal plate
2. a. young chondrocytes undergoing cell division
2. b. chondrocytes enlarged
2. c. chondrocytes trapped during calcification and die
2. d expansion of bone
3. _ - protrudes above and touches upon the epiphyseal plate
4. blood vessels
5. osteoids - separate the osteoblast structures (look like pink teeth)
osteoblasts
_ divide, produce cartilage, then degenerate in the growth of long bones
chondrocytes
_ deposit osteoid which becomes calcified creating bone tissue in the growth of long bones
osteoblasts
Calcification is the deposit of _ _ crystals onto osteoid which creates bone tissue in the growth of long bones
calcium phosphate crystals
Under the influence of GH and mostly _, chondrocytes divide and enlarge, producing cartilage in the epiphyseal plate
insulin-like growth factors
Increased _ in the epiphyseal plate elongates the bone
cartilage
Chondrocytes degenerate and _ move in to create bone
osteoblasts
Osteoblasts convert cartilage to bone, which becomes _
calcified
Bone _ is the laying down of new bone, whereas bone _ is the breakdown of bone
deposition;
resorption
Bone _ is important for calcium homeostasis
resorption - breakdown of bone
- we are concerned about calcium levels as we get older, so we monitor the resorption to determine whether calcium amounts are appropriate
Acromegaly occurs when too much GH release that occurs BEFORE/AFTER epiphyseal plate closure
after - facial features are different, with proliferation in various sites (e.g., larger lips, undereyes, etc.)
Gigantism occurs when too much bone growth occurs BEFORE/AFTER epiphyseal plate closure
before
What would you expect to see in a person with too much GH because of a pituitary tumour?
a. decreased osteoblast activity in bone tissue
b. increased number of chondrocytes
c. decreased IGF-1
d. increased levels of GHRH
b. increased number of chondrocytes
it’s not d because the negative feedback loop would prevent GHRH from being too much, when the tumour is in the pituitary gland, not the hypothalamus
Anti-diuretic hormone is made in the _ but released in the posterior pituitary to increase water reabsorption in the kidney
hypothalamus
Oxytocin is made in the _ but released in the posterior pituitary and promotes labour contractiosn and milk ejection
hypothalamus
Body growth is promoted by _ hormone, which is secreted by the anterior pituitary and acts to promote the growth of soft tissues and bones
growth
Create a hormone summary chart. refer to notes
!
In some cases, individuals are born with antidiuretic hormone receptors that do not function as well as
normal. What would you expect to observe in these individuals?
a. produce a small volume of very salty urine
b. have a higher than normal level of ADH in their blood
c. produce a large volume of very salty urine
d. be unable to sense a change in plasma osmolarity
b. have a higher than normal level of ADH in their blood
Caffeine inhibits the breakdown of cAMP in cells. What would you expect to observe in cells following the activation of the cAMP second messenger pathway in cells treated with caffeine in comparison to untreated cells?
a. higher concentrations of G proteins in plasma membranes
b. higher activity of protein kinase A
c. higher activity of adenylate cyclase
d. higher degree of phosphorylation of all cellular proteins
b. higher activity of protein kinase A
Which of the following is correct about bone growth?
a. growth in childhood occurs at the region of the bones where the yellow marrow is located
b. in childhood, IGF stimulates chondrocyte division in the epiphyseal plate
c. chondrocytes are responsible for the mineralization of cartilage to form bone
d. in adulthood, growth hormone stimulates the division of chondrocytes in the epiphyseal plate
b. in childhood, IGF stimulates chondrocyte division in the epiphyseal plate
What is the structure/purpose of the hormone response element?
a. it is a specific hormone receptor that is found on the cell surface and binds to a specific hormone
b. it is a specific sequence of DNA that binds to a specific hormone/receptor complex
c. it is a specific gene that codes for a specific hormone receptor
d. it is a specific hormone receptor that binds to a specific hormone
b. it is a specific sequence of DNA that binds to a specific hormone/receptor complex
Which of the following is correct about the structure and regulation of the hypothalamus/pituitary?
a. posterior pituitary hormones are regulated by hypothalamic releasing and inhibiting hormones
b. there are fewer cell types in the anterior pituitary in comparison to the number of cell types in the posterior pituitary
c. hormones regulating the function of the anterior pituitary cells are secreted into the posterior pituitary
d. hypothalamic neuroendocrine cells regulating anterior pituitary function have shorter axons than those involved in posterior pituitary function
d. hypothalamic neuroendocrine cells regulating anterior pituitary function have shorter axons than those involved in posterior pituitary function
Which of the following correctly describes a pathway for secretion of a hormone under the control of tropic hormones?
a. CRH stimulates ACTH release, which stimulates somatomedin release
b. PRH stimulates PH release, which stimulates prolactin release
c. GnRH stimulates dopamine release, which stimulates prolactin release
d. GHRH stimulates GH release, which stimulates insulin-like growth factor release
d. GHRH stimulates GH release, which stimulates insulin-like growth factor release
All of the following anterior pituitary hormones listed below stimulates the release of another hormone EXCEPT.
a. growth hormone
b. adrenocorticotropic hormone
c. follicle stimulating hormone
d. prolactin
d. prolactin
Which of the following changes in plasma levels would be observed in a primary hyposecretion of cortisol?
a. decreased CRH, decreased ACTH, and decreased cortisol
b. decreased CRH, decreased ACTH, and increased cortisol
c. increased CRH, increased ACTH, and increased cortisol
d. increased CRH, increased ACTH, and decreased cortisol
d. increased CRH, increased ACTH, and decreased cortisol
Oxytocin is produced by neurons of the supraoptic nucleus in the hypothalamus, but is released into the bloodstream where?
a. uterus
b. posterior pituitary
c. capillary beds of the median eminence
d. anterior pituitary
b. posterior pituitary
Lipophilic chemical messengers are poorly soluble in water. However, many of these lipophilic messengers are transported throughout the body. Their transport in blood (water) is facilitated by
a. carrier proteins
b. lipoproteins
c. chylomicrons
d. red blood cells
a. carrier proteins
Which of the following affect the magnitude of a cell’s response to a specific hydrophilic hormone?
a. number of receptors
b. all answers are correct
c. hormone concentration
d. presence of a receptor for the hormone
b. all answers are correct
What enzyme is activated by cAMP?
a. tyrosine kinase
b. protein kinase C
c. adenylate cyclase
d. protein kinase A
d. protein kinase A
What is the structure/purpose of the hormone response element?
a. it is a specific hormone receptor that is found on the cell surface and binds to a specific hormone
b. it is a specific gene that codes for a specific hormone receptor
c. it is a specific sequence of DNA that binds to a specific hormone/receptor complex
d. it is a specific hormone receptor that binds to a specific hormone
c. it is a specific sequence of DNA that binds to a specific hormone/receptor complex
