Quiz 11 (exam 3) Flashcards
Feedback mechanisms generally involve what four features?
System variable
Set point
Detector
Corrective mechanism
List three things that hormones can control
Rates of enzymatic reactions
Movement of ions or molecules across membranes
Gene expression and protein synthesis
The thyroid hormones are produced from the _____ and control ______
Thyroid
Metabolism
Cortisol is produced from the _____. It is involved in….
Adrenal cortex
Energy metabolism
Stress response
Mineralocorticoids is produced from the ____ and functions to …..
Adrenal cortex
Regulates plasma volume effects via on serum electrolytes
Vasopressin (ADH) is produced from the ______ and functions to _____
Posterior pituitary
Regulates plasma osmolality by altering aqueduct concentration in collecting duct
Parathyroid hormone is produced from the _____ and functions to…..
Parathyroids
Regulates calcium and phosphate levels (increases blood calcium)
What are four factors that effect circulating hormone levels?
Synthesis and secretion rates
Rates of inactivation
Receptor binding or availability of receptors
Affinity of a given hormone for plasma carriers (bound forms = inactive forms_)
What are the three chemical classifications of hormones?
What are the solubility/polarity classifications of hormones?
Amine (tyrosine derivative)
Peptide
Steroid
Lipophilic/hydrophilic
Which has a longer half life peptide or steroid hormones?
Steroid hormones
What are the two types of amine derived hormones?
Catecholamines
Thyroid hormones
Catecholamines are lipophilic or hydrophilic? What about thyroid hormones?
Catecholamines - hydrophilic
Thyroid hormones - lipophilic
Which have longer half lives, thyroid hormones or catecholamines?
Thyroid hormones
What types of hormones are the most numerous in the body?
Peptide hormones
Peptide hormones are produced by first creating ____ which can then be cleaved to an active form
Preprohormones
Protein hormones can be bound to carrier proteins to increase their lifetime. When bound to carrier proteins are they considered active or inactive?
Inactive
What are the three steps to produce peptide hormones?
Genes from DNA is transcribed then translated to produce protein precursors
Preprohormone is formed in ER before broken down to pro hormone in the golgi
Posttranslational modifications occur in the golgi. Then secreted. Post secretory modifications may occur
All steroid hormones are derived from…
Cholesterol
True or false… steroid hormones must be carried in plasma by hormone-specific plasma binding globulins
True. Like albumin
What is the aromotase enzyme?
Converts androgens to estrogens. Performed by trophoblastic tumors in the brain and some normal adipose tissue. They use hormones circulated in the blood to convert to different hormones
Where is most estrogen produced in post menopausal women?
Adipose tissue
What is the difference between the long-loop negative feedback and short-loop negative feedback?
Long loop negative feedback - the hormone released from the endocrine gland will inhibit the hypothalamus and the pituitary gland
Short loop negative feedback - the tropic hormone (hormone that goes from anterior pituitary to endocrine gland) will inhibit the hypothalamus
Which the anterior or posterior pituitary gland is connected to the hypothalamus?
Posterior pituitary
What is the infundibular stalk?
Structure that connects the posterior pituitary to the hypothalamus
What is the hypohyseal portal system?
Surrounds the anterior pituitary. Hypothalamic releasing hormones are released in here to get to the anterior pituitary. In the posterior pituitary, on the other hand, the hormones are directly produced by the neurons in they hypothalamus
The adrenocorticotropic hormone is released from the ____ and will have an effect on the ____, to cause…..
Anterior pituitary
Adrenal gland
Helps regulate fluid balance, helps body cope with stress
What maintains the control of ADH secretion?
Hypothalamic osmoreceptors (ADH is actually produced in the hypothalamus but stored in the posterior pituitary
All adrenocortical hormones are ____ derived. List the three different types and in what layer of the cortex they are found
Steroid derived
Mineralocorticoids - zona glomerulosa
Glucocorticoids - zona fasciculata
Adrenal androgens - zona reticulata
The adrenal medulla secretes….
Catecholamines like epinephrine
Aldosterone is a ____ and promotes ____ reabsorption and potassium _____
Mineralocorticoid
Sodium
Excretion
It has its affect on the collecting duct and distal tubule
What is aldosterone escape?
Too much aldosterone. Persistently elevated extracellular fluid, results in pressure dieresis in the kidneys.
Without aldosterone, the kidney loses excessive amounts of sodium and water.
What happens when aldosterone secretions are increased?
Hypokalemia (results in muscle weakness)
Whenever sodium is reabsorbed, potassium is excreted, resulting in low levels of potassium
What is a result of decreased levels of aldosterone?
Hyperkalemia - may lead to cardiac toxicity
Cortisol is a ____ and it functions to…
Glucocorticoid
Stimulates gluconeogenesis in the liver and decreases glucose use in hepatocytes.
Basically it results in an overal increase in serum glucose
It also decreases protein stores by Inhibiton of protein synthesis and promotes protein catabolism
True or false… cortisol also has an anti-inflammatory effect
True
What are some hormones that are considered adrenal androgens? What do they do?
DHEA, androstenedione.
It will basically result in an increase of male sex hormones
ACTH will caus an increase in what two hormones?
Adrenal hormones and cortisol
The sympathetic nervous system will cause the adrenal medulla to secrete 80% of ____ and 20% of ____
Epinephrine
Norepinephrine
The ____ is involved in the acute stress response while the ____ is involved in the long-term stress response
Medulla
Cortex
Describe the cortisol regulation by the HPA axis
Hypothalamus is signaled by stress, circadian rhythm, or pro-inflammatory cytokines to release CRH
CRH stimulates the anterior pituitary to release ACTH (adrenocorticotropic hormone).
ACTH will cause the release of cortisol, and adrenal hormones. Cortisol will suppress both CRF and ACTH release in a negative feedback loop
What are the three main types of endocrine disorders?
Endocrine gland hyposecretion (type 1 diabetes)
Hormone resistance (type two diabetes)
Hormone excess (acromegaly)
What causes addisons disease? What are its symptoms?
Adrenal insufficiency
Causes fatigue, stomach upset, dehydration, skin changes
Excessive production of what hormone results in Cushing’s syndrome? What are its symptoms?
ACTH, which results in overproduction of cortisol
Red cheeks, bloated stomach with stretch marks, tumors
What are the differences between hypothyroidism and hyperthyroidism?
Hypothyroidism - not enough thyroid hormones leads to fatigue, hashimotos disease, depression
Hyperthyroidism - too much thyroid hormone leads to fast heart rate, sweating, bulging eyes.
Both can result in goiters
The sphenopalatine artery arises from ____ and will supply _____
3rd part of maxillary artery
Incisive foramen
Greater palatine artery arises from _____ and supplies ____
3rd part of maxillary
Greater palatine foramen
Lesser palatine artery arises from ____ and supplies ____
3rd part of maxillary
Lesser palatine foramen
The ascending palatine artery arises from ____ and supplies blood to ____
Branch of facial
Serves the soft palate
The ascending pharyngeal artery arises from ___ and serves blood to the _____
Branch of ECA
Serves the soft palate
The superior labial nerve branches from what nerve?
Branches from infraorbital, which is a branch of V2
The middle superior alveolar branch is a branch from what nerve?
Infraorbital nerve, which is a branch of V2
The long buccal nerve is a branch from…?
Trigeminal. V3
Buccal is motor from facial
Long buccal is sensory from
V3
The greater and lesser palatine nerves are branches from…?
Pterygopalatine ganglion
What is the bartholin?
Duct that drains into floor of mouth via sublingual caruncle
The sublingual gland is innervated by…
Chorda tympani. Via lingual branch of V3
What is the saliva composition of the sublingual gland?
5% saliva, mixed but mostly mucous
What is the duct that drains the submandibular gland into the floor of mouth via sublingual ____?
Warhtin’s duct
Caruncle
What artery supplies the submandibular gland?
Facial artery
What is the name of the duct that drains the parotid gland? Wher does it drain?
Stensen’s duct drains into rear/upper area
What is the innervation of the parotid gland?
Lesser petrosal via V3 (aurictemporal)
What artery supplies the parotid gland?
Transverse facial branches of superficial temporal
Which salivary gland produces amylase?
Parotid
What are Sialoliths?
Stones of the parotid gland that blocks the ducts, causes pain and swelling
In the ovary, ____ cells provide androgens which stimulate the ____ cells and produce the circulating ____
The cal
Granulosa
Estrogens
Estrogens feedback inhibit….
GnRH
LH
FSH
Inhibits are produced from ____ cells and these function to inhibit _____
Granulosa
FSH secretion
LH stimulates ____ cells, while both LH and FSH stimulate ______ cells
Thecal
Granulosa
All natural estrogens are characterized by ….
18 carbon skeleton called an estrane skeleton
Estradiol (E2) is predominant when?
What about Estrone (E1)
What about Estriol (E3)
Reproductive years
Menopause
Pregnancy
List 8 things that estrogens can do
Sexual maturation
Increase CNS excitability
Stimulate endometrial proliferation and uterine growth
Maintenance of healthy blood vessels Increase SHBG Reduce rate of bone readsorption Alter plasma lipids (Increase HDL) Enhance blood coagulability
Estrogen is ____ during menses. So the pituitary makes and secretes ____ and _____
Low
FSH and LH
Prior to ovulation, LH acts predominantly on the ____ cells
Theca
What causes the LH surge that causes ovulation?
Estrogen inhibits the release of LH. Once enough is built up enough it is released because the high levels of E2 reaches a tripping point in which it briefly flips the GNRH feedback from negative to positive. This stimulates the hypothalamus to release mor GnRH which tells the anterior pituitary to release LH and some FSH
How long does it take for ovulation to occur after the peak of the LH surge?
10-12 hours
Explain the ovulatory mechanism
Includes the release of metalloproteinases that weaken the ovarian wall; blood flow to the area stops and the follicle wall thins and ruptures, allowing the egg to be released
What occurs in the luteal phase
Begins at ovulation, the remaining ovarian cells become the corpus luteum and produces some E2 but mostly a boat load of progesterone. This lasts ~14 days
What does progesterone do?
Inhibits pituitary release of LH and FSH, usually preventing a second ovulation event
Prepares the uterine wall for implantation (more vascularized and thickening)
If fertilization doesn’t occur, the corpus luteum degenerates, (thus less progesterone), and becomes the corpus albicans, and shedding results (menses)
Following ovulation, what cells converts enzymatic activity from predominantly estrogen-producing to progesterone producing as the corpus luteum develops/
Granulosa cells
True or false, progesterone (a progestin) is a precursor to the synthesis of all estrogens
True
What are some physiological effects of progesterone?
Prepares uterus for implantation Plays a role in the development of the secretory mechanism of the breast Increases fat deposition Decrease CNS excitability Increase insulin levels Increases body temp Decreases PCO2 during pregnancy
Critical body weight must be erased for puberty in women to occur. Involves leptin. How does leptin start the process of ovarian cycle stuff?
If leptin levels are adequate, the hypothalamus becomes less sensitive to estrogen and GNRH release begins
True or false… ovulation usually begins with the menarche (first menses)
False
What is perimenopause?
Can proceed menopause by 1-10 years.
Fluctuations of gonadotropins and estradiol levels are observed , believed to be due to loss of inhibins. (Loss of inhibition of FSH)
At onset of menopause, ___levels are markedly elevated
FSH
In postmenopausal women, what estrogen is formed from testosterone by _____ in _____
E1
Aromatase enzyme in adipocytes
Upon implantation, _____ cells begin secreting ______, which functions to ….
Trophoblast
hCG
Supports the corpus luteum which is producing progesterone which functions to spport the endometrial lining and therefore maintains pregnancy
What are progesterone’s effects during pregnancy?
Prevents uterine contractions
Moderates maternal immune response to preserve pregnancy
Stimulates lobular-alveolar development in mammary glands
Suppresses milk synthesis until child birth
What takes over the production of progesterone by about week 8 if pregnancy occurs?
Placenta
How is estrogen involved in parturition?
Induces oxytocin receptors on uterus
What is relaxin’s role in partuition?
Peptide hormone secreted by the placenta to relax the cervix and pelvic ligaments to ease birth
Prolactin is under predominant inhibitory control. What inhibits its release?
Prolactin inhibitory factor (dopamine) which is secreted by the hypothalamus
Milk ejection is promoted by what hormone?
Oxytocin (positive feedback)
The first fluid released from breast after birth is called ____. It is high in _____ but low in ____
Colostrum
Proteins/carbohydrates
Fat
The head of the sperm contains the ____ which is….
Acrosome
It is a vesicles full of enzymes that can breakdown the outer layer of the ovum during the acrosome reaction. This will allow fusion of the sperm with the ovum
Other than DNA, what else does the sperm cell contribute to the ovum?
Centrioles (which are a complex of micotubules)
What is the axoneme?
A cytoskeleton component of the sperm flagella which is formed from microtubules.
The seminiferous tubules are lined with _____ (which are ____)
Spermatogonia
Diploid germinal epithelial cells
Spermatogonia can undergo mitosis or meiosis… true or false
True
What are serotoli cells?
These are ‘nurses’ that surround the spermatogonia to help them sperm cells develop. They also for the blood-testis barrier
The leydig cells lay on the outer surface of the seminiferous tubules. They produce ____ in response to ____, which initiatives spermatogenesis
Testosterone
LH
How long does it take for spermatogenesis to occur?
64 days
What is inhibin’s role in hormonal control of spermatogenesis?
Produced by sertoli cells
Negative feedback of anterior pituitary to inhibit FSH release (acts on anterior pituitary)
What is the role of Growth Hormone in the hormonal control of spermatogenesis?
Basic total regulation of metabolism of testes
LH stimulates ___ cells while FSH stimulates _____ cells.
____ is secreted by leydig cells which drives division of spermatogonia
Sertoli cells secrete ____ which regulates spermatogenesis. This hormone is formed from ____
Leydig
Sertoli
Testosterone
Estrogen
Testosterone
What is the tubulus rectus?
Connection of seminiferous tubules with the rete testes
What is the rete testes?
Tubule which delivers maturing sperm to the epididymis and serves to reabsorb some tubular fluid, the concentrating the sperm
Once the sperm are in the epididmyis for about a day….
They are capable of movement (they mature), but they do not move because they are inhibited by the factors in the fluid
What are some things that the seminal vesicles add to the mixture?
Fructose: fuel for sperm motility
Prostaglandins: thin cervical mucus, allowing sperm ingress, and possibly causing reverse peristaltic contraction bringing sperm inwards (?)
Fibrinogen: functions to form a clot later on
The seminal vesicles contribute about ____% of the final product
60-70
Through what structure does the semen pass to enter the prostate?
Internal urethra
What are some things that the prostate gland adds? What do they do?
Clotting enzymes: causes semen to clot (more likely to result in fertilization)
Pro-fibrinolysin: can helpfully breakdown the clot semen forms
Various alkaloids: neutralizes the pH of the vagina somewhat for better sperm survival and motility
In total, the prostate gland contributes ____% of the final product
25-30
How much of total semen is actual sperm?
5%
What do bulbouretrhal glands do? What percent do they contribute to the total semen?
Lubricant for the urethra to help sperm along
Can transmit disease
1% of total final ejaculate volume
What pH is the semen?
7.5
What gives semen its milky appearance?
Fluid from the prostate
Sperm can survive in utero for how long?
2-3 days
Describe sperm capacitation
Semen contains mobility inhibiting factors
Upon entering the vagina these are washed away, ‘capacitating’ the sperm’ meaning that the become motile.
The cell membrane around the acrosome weakens allowing easier rupture
Calcium permeability increases which causes a more vigorous motion of flagella
Pre-ejaculate is released in response to the _____ nerves
Parasympathetic (S2-4)
What factors causes vasodilation in the penis?
NO, ACH, other vasoactive transmitters
What nerves cause contraction of the vas deferens to move the sperm towards the seminal vesicles?
Sympathetic
Define emission
Passing of future ejaculate into the prostate, then passing into the internal urethra where it mixes with bulbourethral gland
Describe the order of type of epithelium found in salivary glands from innermost to outermost.
Intercalated - simple cuboidal
Striated - simple columnar
Interlobar - stratified columnar
Which branch of V does not run through the cavernous sinus?
V3
What artery ascends within the parotid gland?
Superficial temporal
What nerve innervates the tensor veli palatini muscle. Specifically
Pterygoid nerve from V3
True or false… the inferior thyroid supplies part of the pharynx
True
If the macula densa senses a decrease in the NaCl concentration, it means that the GFR is too ____
Low
The sodium potassium ATPases that are used to set of the concentration gradient to help pull things like hydrogen ions and glucose across the cells into the peritubular capillaries are located where?
On the basolateral side of the cell
Where does most water readsorption take place in the kidney?
In the loop of henle
What is the primary precursor for amino acid production?
Glucose
The large subunit of the ribosome binds to the mRNA after ____ has already attached?
The methionine anticodon
About what day of the menstral cycle does ovulation occur?
Day 13
A woman’s first ovulation could occur how many years after her first menstruation?
2-4 years
What nerve gives sensation to the uvula?
Lesser palatine
Enzymes that produce steroid hormones are located in what organelles?
Mitochondria and smooth ER.
How is the adrenal medulla stimulated to produce catecholamines?
Ach from sympathetic nerves
