Exam 1

Parathyroid Glands Produce

(on posterior surface of thyroid gland); Parathyroid hormone (PTH)

A woman reports to a fertility clinic and several tests are performed. It is determined that the women does not make estrogen in her ovary although all the required cells are present. List and explain at least three different defects that could be present in the ovary that would result in an inability to make estrogen.

-excessive scar tissue -theca cells not producing androgen -defective aromatase -defective LH/FSH receptors -too much inhibin

How it is possible for an XX individual to have XY genitalia?

1) 21-hydroylase deficiency: congenital adrenal hyperplasia 2) SRY translocation: recombination of SRY from Y to X

How it is possible for an XY individual to have XX genitalia?

1) 5α-reductase deficiency 2) SRY inactivation 3) Androgen insensitivity -> receptor mutuation

Describe the events that occur during the LH surge, including the actions of LH on target cells.

1) Follicles incr estrogen (turns on (+) feedback onto hypothalamus and Ant Pit 2) LH surge in Ant Pit gonadotropes 3) Ovulation of Secondary oocyte 4) Formulation of Corpus Luteum (transient endocrine gland) 5) CL secretes progesterone 6) Progesterone maintains/ prepares the endometrium for implantation

Which neuroendocrine hormonal cell bodies are located in specific nuclei?

1) Paraventricular Nucleus (PVN)- produce ADH and oxytocin 2) Supraoptic nuclei (SON)- produce ADH and oxytocin 3) Suprachiasmatic nucleus (SCN)- controls circadian rhythms 4) Arcuate nucleus (ARC)- produces hypothalamic releasing factors 5) Preoptic area (POA)- regulates release of gonadotropic hormones

What are the phases of the Ovarian cycle? What is happening during each phase (be sure to mention hormone levels)?

1. Follicular phase: follicle growth in the ovary, increased estrogen production Ovulation: LH surge cause the Graafian follicle to release secondary oocyte 2. Luteal Phase- ruptured follicle turns in to the corpus luteum, increased progesterone production (and estrogen)

Characteristics of the Endocrine System

1. Glands that secrete chemical messengers (hormones) into circulatory system 2. Hormone characteristics - Produced in small quantities -Transported some distance in circulatory system - Acts on target tissues elsewhere in body-- vary in their pattern of secretion

Describe the 4 stages of spermiogenesis?

1. Golgi Phase- sperm develop polarity 2. Cap/Acrosome Phase- golgi surrounds condensed nucleus forming acrosomal cap 3. Tail Phase- centriole elongates to become tail 4. Maturation Phase- excess cytoplasm is shed & phagocytosed by Sertoli cells. Sperm are mature but they lack motility @ this phase. They gain motility in the epididymis.

What are three ways hormone secretion can be stimulated?

1. The action of a substance other than a hormone on an endocrine gland-humoral control 2. Neural control of endocrine gland (adrenal) 3. Hormonal control- control of secretory activity of one endocrine gland by hormone or neurohormone secreted by another endocrine gland (pituitary gland)

During Fetal development, _______1______________cell division of germinal cells forms millions of _____2___________, but most of them degenerate. Survivors become __________3________________oocytes containing _______4________chromosomes. Single layers of follicular cells envelop each oocyte forming ____5__________________ follicles, but most of them degenerate; the survivors become _____________6______________follicles. After puberty, usually_______7______ dominant follicle develops each month, and its ooctye undergoes the first _________8______________division producing a __________9__________oocyte and the first__________10______________. Both of these cells contain ____11________chromosomes. Continued growth results in rupture of the follicle at ________12______________, and the released oocyte enters the________13______________ tube. If the secondary oocyte is penetrated by a ___________14_________________, the second______15____________________ division forms an _______16__________________ and the second_________17__________________, each with _________18__________ chromosomes.

1. mitotic 2. oocytes 3. primary 4. 46 5. primordial 6. primary 7. 1 8. meiotic 9. secondary 10. polar body 11. 23 12. ovulation 13. fallopian/ uterine 14. spermatazoan (sperm) 15. meiotic 16. ovum 17. polar body 18. 23

The _______1_______feedback mechanism controlling labor is started by pressure of the fetus on the______2_______, which sends impulses that are carried to the hypothalamus. The hypothalamus then stimulates the _______3__________ to secrete ______4_________that stimulates uterine______5__________. This pattern of feedback produces increasingly stronger contractions until the baby is born.

1. positive 2. cervix 3. posterior pit 4. oxytocin 5. contractions

How long does an oocyte live following ovulation? What happens to the Oocyte if fertilization does not occur?

12-24 hours, degraded

At what stage of spermatogenesis does meiosis I occur? How many chromosomes are present after meiosis I?

2, 23

How many sperm are typically released into the female reproductive tract and how long do they live?

200-300 million sperm, 3 days

Explain why defects in biosynthesis of cortisol can give rise to Congenital adrenal hyperplasia.

21-hydroxylase, prevents the production of cortisol and aldosterone, so when body tries only pathway is the one to create androgens

What is the pH of the vagina and why is that important?

4-4.5, acidic to prevent infection

What are biological effects of T3 action?

4x more active than T4

Describe how T4 is converted to T3?

5'-deiodinase converts T4-> T3 + rT3

What enzyme converts testosterone to DHT?

5a-reductase

What are nuclei?

A cluster of cell bodies

General characteristics of hormones

A. Stability B. Communication: Interaction w/ target cell

Explain the role of aldosterone, AVP and ANP in salt balance regulation

AVP losses salt, Aldosterone incr salt, ANP sends sodium load to kidney, inhibits Na+ reabsorption, decreases Na+ and H20=> decr blood volume=> decr blood pressure

Describe the major structural and functional regions of sperm.

Acrosome - on top of head, helps penetrate egg Dna - in head Mitochondria - around base of tail Tail- motility

What is the hormonal control of Sertoli cells?

Activated by FSH

How is the oocyte moved towards the uterus? How many days does it take the oocyte to travel and ultimately implant?

Activity of the cilia of tubes, Muscular contraction of the tube which during ovulation 3-7 days

Hormones of the Anterior Pituitary

Adrenocorticotropin (ACTH) Thyroid-stimulating hormone (TSH) Growth Hormone (GH) Prolactin (PRL) Luteinizing hormone (LH) Follicle- stimulating hormone (FSH)

Explain role of aldosterone, vasopressin (AVP or ADH) and atrial natriuretic peptide (ANP) in blood pressure regulation.

Aldosterone: incr Na+ uptake and water Vaopressin: stimulate production of aquaporins in tubular cells of distal tubule Renin-> Angiotensin I-> angiotensin 2-> AVP increase blood pressure ANP inhibits Vasopressin, aldosterone and renin, ECF volume goes up and causes release of ANP

Types of Hormones

Amine- thyroid hormones (tyrosine der. and Epinephrine and norepinephrine, serotonin precursor and melatonin), peptide (largest # of hormones and water soluble), protein, Steroid

explain how an anatomical female can occur in an XY person

Androgen Insensitivity Syndrome (Testicular Feminization Syndrome lack functional androgen receptors so cells can't respond to testosterone, no wolffian duct development, MIS secreted so Mullerian duct regresses external female genitalia form b/c testosterone can be aromatized to estrogen in peripheral tissues (fat) femal secondary sex characteristics form but no menstruation

Pituitary Gland Produces

Anterior lobe: ACTH, TSH, GH, PRL, FSH, LH, and MSH Posterior lobe: Release of oxytocin and ADH

Takes over secretion of estrogen and Progesterone In second-third month

CL

Draw the hypothalamo-pituitary-adrenal (HPA) axis and understand the negative feedback circuit

CRH (corticotropin-releasing hormone) -> Corticotroph cells of Anterior pituitary-> ACTH released-> adrenal cortex releases Mineralocorticoids, Glucocorticoids, DHEA(S), cortisol cortisol inhibits anterior pituitary and Hypothalamus

What is cervical effacement? What is the mucus plug? Chadwick's sign?

Chadwick's sign: color change to discoloration or bluish purple hue to cervix, vagina, and vulva (one of earliest signs of pregnancy) Mucus plug (operculum): cervical mucus fills endocervical canal, keeps harmful organisms out of the uterus cervical effacement: cervix thins out

What are Granulosa cells? What major enzyme is expressed and why is it important?

Converts androgen to estrogen, aromatase , testosterone to estrogen

A new born baby is born with a pendrin mutation. Explain what can be expected if the baby goes untreated?

Creatinism

Adrenal Glands produce

Each adrenal gland is subdivided into: Adrenal medulla: Epinephrine (E), Norepinephrine (NE) Adrenal cortex: Cortisol, corticosterone, aldosterone, androgens

Describe the three germ layers what organs they ultimately become.

Ectoderm: epidermis, nervous system Mesoderm: circulatory system, reproductive system, skeletal system, muscular system Endoderm: digestive tract, respiratory system

What hormone is Secreted by follicular cells?

Estrogen and a little bit of progesterone

What is the main stimulus for the proliferative phase of the endometrium? What happens to the endometrium during the proliferative phase of the menstrual cycle?

Estrogen levels rising, generates a new functional layer

What hormone Stimulates the development of ovarian follicles?

FSH

What hormone is Secreted by the hypothalamus?

GnRH

What is the main trigger for the "LH surge"?

High levels of estrogen

The posterior pituitary is not really a true endocrine gland, why not? Discuss the specific hypothalamic nuclei that are important for posterior pituitary function.

Hormones not actually being made in post pit Oxytocin and ADH are produced in supraoptic nuclei and paraventricular nuclei of hypothalamus and just released from posterior pit

What is hCG? What cells are secreting it and where does it bind? Why is it important?

Human Chorionic Gonadotropin, fetus, corpus luteum, hormone used to test for pregnancy

Describe the role of the hypothalamus in regulation of the anterior pituitary hormone secretion. How do hypothalamic hormones reach the anterior pituitary and why is that important?

Hypophyseal portal system - (portal system is just a system with 2 stops before it gets back to the original spot) from hypothalamus to blood -important because peptide hormones -> short half life, need to get them to receptor asap -specific action -> only want it to have action on the anterior pituitary -> undetectable in jugular blood

LH

Increases ovarian progesterone synthesis, luteinization; acts on Leydig cells of testes to increase testosterone synthesis and release and increases interstitial cell development

Describe Renin

Juxtaglomarular cells in kidney, enzyme, cleave angiotensinogen to Ang I

What hormone Stimulates the development and function of the corpus luteum?

LH

What are the cells that produce androgens, and where are they located? What are the factors that influence production of androgens in the testis?

Leydig cells, found in between the seminiferous tubules and testes, LH levels

Function of the hypothalamus from Endocrine standpoint?

Link the nervous system via pituitary It synthesizes and releases hypothalamic releasing hormones which stimulate or inhibit secretion of the pituitary hormones

In an effort to prolong the years of female reproduction, a drug company wants to produce a drug that prevents more than one follicle from maturing with each menstrual cycle. Which of the following might be a side-effect of this drug? Lower GnRH levels Higher circulating estrogen levels in the luteal phase Lower circulating progesterone levels in the luteal phase Lower circulating progesterone levels in the follicular phase Lower circulating estrogen levels in the follicular phase

Lower circulating estrogen levels in the follicular phase

What cells are responsible for the blood-testis barrier and what are some unique features that are important for creating the barrier? Why is the blood testis barrier important?

Luminal Sertoli cells, protect haploid cells against immunological recognition as non-self and subsequent antibody-mediated attack

ACE

Lungs, Ang I -> Ang II, enzyme

At what point in the ovarian cycle would you expect cervical mucus to be its thickest? Luteal Follicular Secretory Ovulation Menses

Luteal

describe how a male is made from a female

MIS is released causing Mullerian ducts to regress, testosterone causes Wolffian ducts develop internal male gentitalia then is converted to DHT creating penis, scrotum and prostate

How does oogenesis differ from spermatogenesis? (gametes produced, timing, meiosis I/II, etc.)

Males: starts at puberty, Meiosis I happens then meiosis II to secondary spermatocytes crating spermatid, spermatogenesis happens, 4:4 Females: start before birth (born with max # before birth) Meiosis II after fertilization, ovum at end, 4:1

At what stage is the oocyte at the time of ovulation? How many chromosomes does it have?

Meiosis I, 23

In what phase of replication are primary oocytes arrested?

Meiosis II

Pineal Gland Production

Melatonin

What are the phases of the Uterine cycle?

Menses (shedding endometruim, hormones at low levels), proliferative, Secretory

How does T3/T4 leave the cell?

Monocarboxylate transporter (MCT) facilitates the exit out of the follicular cells,TGB carriesitintheblood

Solid ball of cells formed by cleavage

Morula

What point in the ovarian cycle would you expect cervical mucus to be the thinnest? Secretory Ovulation Luteal Menses Proliferative

Ovulation

Hormones of Posterior Pituitary

Oxytocin and Antidiuretic hormone (ADH, Vasopressin)

What is Pendrin and why is it important?

Pendrin- Cl-/I- counter transporter. mediates exchange for iodide across the apical membrane Must have functional pendrin to make Thyroid hormone

List the subdivisions of the pituitary gland.

Posterior and Anterior

Describe Vasopressin/ADH

Posterior pituitary, peptide, incr aquaporins (incr H2O reabsorption), distal tubule/ collecting duct in kidney

What are the different stages the follicle goes through during each monthly cycle?

Premordial follicles, primary follicle, Secondary follicle, Vesicular (Graafian) follicle, ovulating follicle, corpus luteum, corpus albicans

Describe peptide hormone production and storage.

Preprohormone tell go to ER becomes prohormone-> golgi -> secretory vesicle-> release signal to extracellular space

Hypothalamus Production

Production of ADH, Oxytocin, and regulatory hormones

What hormone Maintains uterine lining in pregnancy?

Progesterone

What hormone Prepares the endometrium for pregnancy?

Progesterone

What hormone in High concentrations inhibit GnRH secretion?

Progesterone

What hormone is Secreted by the Corpus Luteum?

Progesterone (some estrogen)

explain how an anatomical male can occur in an XX person

SRY-containing translocation to X chromosome- 46.XX de la Chapelle Syndrome

List the key characteristics of Sertoli cells (what do they produce?) List the two compartments of Sertoli cells.

Secretes Anti-Mullerian hormone (AMH) and Androgen Binding Protein (ABP)- elevates testosterone conc in testes Basal- between basement membrane and Sertoli intercellular junctions luminal- blood-testes barrier

Detail the path of sperm from production to exiting the body

Seminiferous tubule, Epididymus, Vas Deferens, Urethra

Which of the following would likely occur in a woman on the pill? Formation of the corpus luteum No Meiotic Arrest in primary Oocyte Some antral follicle development Completion of the second meiotic division of the oocyte Regression of the zona pellucida Increased corpus albicans secretion

Some antral follicle development

Where are these sperm stored? What is the path of sperm movement through the male reproductive tract?

Sperm stored in tail of epididymis (immature sperm in head of epididymis) SEVU (seminiferous tubules, epididymis, vas deferens, urethra)

Which sperm precursors develop outside of the blood-testis barrier protection? What compartment of the Sertoli cells is this?

Spermatogonia and Primary Spermatocytes basal

What are the 4 stages of Labor?

Stage 1: 0-10cm Stage 2: from complete dilation and effacement to delivery of the baby Stage 3: from delivery of baby to the delivery of the placenta Stage 4: the first hour after delivery

Draw the hypothalamo-pituitary-thyroid axis and describe its negative feedback.

T3 and T4 negatively feedbacks to anterior pit and Hypothalamus

Explain and describe the synthesis and release of thyroid hormones (T3 and T4)

TRH (hypothalamus)-> TSH (Anterior pit)-> thyroid to make T3 and T4 TH uptakes Iodide then DIT and MIT coupling leads to T4 and T3 5'-deiodinase coverts T4 to T3 and rT3

Describe the mechanisms behind (and treatments for) hyperthyroidism and Graves' disease

TSH levels really low, antibody looks like TSH that causes overproduction of T3 and T4

Gonads produce

Testes (male): Androgens (especially testosterone), inhibin Ovaries (female): Estrogens, progestins, inhibin

explain complete androgen insensitivity syndrome

Testis produce testosterone via the Leydig cells. No androgen receptors. Leads to increase in GnRH, which increases LH and FSH secretion. Anatomically female XY

Thyroid Gland

Thyroxine (T4), Triiodothyronine (T3), Calcitonin (CT)

Most contraception options for males target the Vas deferens, can you think of ways the vas deferens can be modified to control fertility?

Vasectomy - ligate vas deferens, no travel of sperm to urethra Reversible vasectomy RISUG - inject gel into vas deferens, blocking path so sperm can't travel to urethra

Receptor on the Zona Pellucida necessary for Sperm binding

ZP3

Describe the Acrosome reaction and why its important.

ZP3-binding molec binds to ZP3 on zona pellucida, sperm releases Hyaluronidase and acrosin (acrosomal enzymes), enzymes digest zona pellucida creating pathway to ovum

1) Which one of the following statements is FALSE? For thyroid hormones and their synthesis, __________________________ a. Iodide is actively exchanged with K+ at the luminal surface of the follicular cell by Pendrin b. Iodide is converted to iodine by the activity of thyroid peroxidase (TPO) c. Thyroxine (T4) is synthesized in greater amounts than tri-iodothyronine (T3) d. T3 is far more active than T4 e. The monocarboylate transporter allows for the exit of T4/T3 from the follicular cell

a

Atrial Natriuretic Factor a. Decreases secretion of Reninb. Increases secretion of aldosterone c. Is secreted by the kidney d. Increases blood pressure e. Decreases potassium levels

a

Based on the ACTH stimulation test results, what type of adrenal insufficiency does JFK have? a. Primary b. Secondary c. Tertiary

a

Based on what you know about the diurnal pattern of cortisol secretion, when would be the best time for JFK to visit the safety deposit boxes that contained his cortisol (so that he could take his mediation)? a. early morning b. late afternoon c. evening d. midnight

a

Ovulation is immediately preceded by which of the following a) A surge of LH b) Lowering estrogen levels c) Production of progesterone d) Release of the egg into the fallopian tube Positive feedback from Testosterone

a

Which of the following is NOT a tropic hormone ________________. a. Prolactin b. Luteinizing Hormone (LH) c. Thyroid stimulating hormone (TSH) d. ACTH e. GnRH

a

JFK had several significant surgeries to repair bones in his back after WWII. He had many complications from these surgeries including poor wound and bone healing. How did his chronic cortisol intake contribute to these complications. Check all that apply. a. poor wound healing due to immune suppression b. his bones are weakened from osteoporosis c. poor wound healing from increased inflammation d. his bones are too dense to properly heal e. poor wound healing because of increased cytokine production

a and b

What results would you expect from someone who has looked at their smart phone for several hours before going to bed? Check all that apply. a. shortened sleep time b. increased melatonin c. increased alertness the following day d. altered circadian rhythm e. increased norepinepherine

a and d

What is the hypothalamus and why is it important from an endocrine standpoint?

a collection of specific regions within the brain is below (hypo) the thalamus

What level of the hypothalamic-pituitary-gonadal axis does the birth control pill target for feedback? Click all that apply. a) hypothalamus b) posterior pituitary c) anterior pituitary d) hypophyseal portal system

a) and c)

Which of the following best describes melatonin secretion? Check all that apply a) increased by darkness b) Secreted on a set biological rhythm and does not change c) synthesis stimulated by norepipherine d) secreted in greater amounts during light exposure e) secreted by the hypothalamus

a) and c)

Which of the following are FALSE about the mini-pill? Click all that apply a) It contains estrogen b) All the pills are active c) It should be taken at the same time every day d) It contains progestin e) It doesn't prevent ovulation

a) and e)

Which are TRUE about the actions of progesterone? Click all that apply a) It induces thick, sticky mucus in the cervix. b) It increases body temperature. c) Induces the LH surge d) Stimulates the secretory phase of the uterine cycle

a), b), and d)

What are the ways that hormonal based birth control (the pill) works to prevent pregnancy? Click all that apply. a) thins uterine lining b) increases length of menstrual phase c) decreases primordial follicles d) no ovulation e) thickens cervical mucus f) increases inhibin production

a), d), e)

Which of the following patients are at risk for developing Cushing's Disease? Select all that apply a. a patient with a pitutiary tumor causing too much ACTH secretion b. patient with adrenalectomy c. patient taking glucocorticoids for weeks d. over functioning of the zona fasciculata e. CRH deficiency

a, c, d

What would be typical symptoms that JFK would be experiencing with Addison's disease? Check all that apply. a. Fatigue b. High sodium in the ECF c. Low blood pressure d. Weight loss e. Muscle weakness

a, c, d, e

TSH

acts on thyroid follicle cells to stimulate thyroid hormone synthesis

Circadian Rhythm in humans: Check all that apply a. is approximately a 24 hour cycle b. Repeats itself c. Can be modified by melatonin d. controlled by the suprachiasmatic nucleus

all of them

What is a goiter? Give examples of how a goiter can form-

an enlarged thyroid gland can get from hypothyroidism- Hashimoto's Hyperthyroidism- Grave's disease

Explain the biological effects of cortisol

anxiety and memory hypertension obesity, lipolysis Myopathy Incr glucose, osteoporosis, antiinflammatory , reduces stored glucose; reduces GLUT4 transport

What happens to the other Graafian follicles that have matured but not ovulated during the cycle?

apoptosis

Shedding of the endometrial lining occurs because of increasing FSH levels because ovulation disrupts the growing follicle. a day after the LH surge. as a result of a fall in plasma levels of estradiol and progesterone. because the nondominant follicles undergo atresia

as a result of a fall in plasma levels of estradiol and progesterone.

An autoimmune disease associated with hypothyroidism is a. Cushing's b. Hashimoto's c. Addison's d. Graves' e. Nelson's

b

Estrogen production in ovarian follicles _________________________ a. Is controlled exclusively by LH b. Involves both thecal cells and granulosa cells c. Is dependent on 5a-reductase enzyme d. Is reduced just prior to ovulation Requires the synthesis of androgens in granulosa cells

b

If the adrenal glands were removed from a patient, his plasma cortisol levels would ________, secretion of CRH by the ________ would ________, and secretion of ACTH by the ________ would ________. a. increase; hypothalamus; decrease; anterior pituitary gland; decrease b. decrease; hypothalamus; increase; adenohypophysis; increase c. decrease; anterior pituitary gland; increase; hypothalamus; increase d. increase; hypothalamus; increase; adenohypophysis; increase e. decrease; adenohypophysis; increase; anterior pituitary gland; increase

b

Which is a result of elevated thyroid hormone levels? a. An increase in triglyceride storage b. Increased ATP production c. Decreased body temperature d. Skin darkening e. High TSH levels

b

Based on the reading, what hormone(s) are likely impaired in JFK? Check all that apply. a. CRH b. Cortisol c. ACTH d. Aldosterone

b and d

Which of the following is correct? Check all that apply a. blue light has a long wavelength b. Melanopsin detects light in the eye c. blue light is best before bed d. Melanopsin is the most sensitive to blue light e. blue light is the most inhibitory to melatonin secretion

b, d, e

Which type of chemical messenger, when released, binds to receptors on the cell that released the chemical messenger? a. paracrine b. autocrine c. systemic hormone d. cytokine e. neurohormone

b- cell releases hormone that binds to same cell

How is thyroid hormone transported in the plasma?

by thyroxine binding globulin (TBG)

A woman with regular menstrual cycles undergoes fertility testing. She has a typical LH surge but has low progesterone through the menstrual cycle. Which of the following is most likely responsible for difficulty? a) Inability to develop mature follicles b) GnRH deficiency c) Inability to develop a healthy corpus luteum d) Estrogen deficiencies e) 5 alpha reductase deficiency

c

An ACTH stimulation test measures how well the adrenal glands respond to adrenocorticotropic hormone. The test is done the following way: Your blood is drawn. You then receive a shot of ACTH After either 30 minutes or 60 minutes, or both, your blood is drawn again. The lab checks the cortisol level in ALL the blood samples (pre/post ACTH stimulation). What result would JFK have if an ACTH stimulation test was administered? a. cortisol would increase b. cortisol would decrease c. no change in cortisol d. cortisol would increase and then return to normal e. cortisol would increase and stay elevated

c

In the differentiation of a normal female: a. Müllerian inhibiting substance (AMH) causes the Müllerian ducts to regress. b. The uterus and fallopian tubes are formed from the Wolffian ducts. c. Female genitalia form in the absence of hormonal stimulation. d. The gonads remain undifferentiated throughout fetal life. e. The SRX protein present on X chromosomes makes the gonads differentiate into ovaries.

c

JFK's ACTH concentrations would be: a. normal b. lower than normal c. higher than normal

c

Which diet makes the most sense for JFK/Addison's disease patient: a. High fat b. low protein c. high carbs and increased sodium d. low protein, increased sodium e. high potassium

c

Which of the following is NOT stimulated by cortisol during stress? a. Gluconeogenesis b. Protein catabolism c. Glucose uptake into muscle cells d. Triglyceride catabolism in adipose cells e. Bone resorption

c

Which one of the following statements about cortisol is TRUE? Cortisol ______________________________ a. Is mainly secreted from the glomerulosa layer of the adrenal cortex b. Is synthesized from androgens c. Reduces antibody production d. Is metabolized to estrogen in renal tubular cells e. Lowest levels are found in the morning

c

Which one of the following statements is TRUE? a. Thyroid hormones are water-soluble, which explains why they pass through cell membranes quite easily. b. Tri-iodothyronine has a strong stimulatory effect on TRH secretion. c. Goiter is due to iodine deficiency or increased iodine demand. d. Thyroglobulin has a tryptophan backbone necessary for T4 synthesis e. Deiodinase expression at target cells converts T3 to T4

c

What path does sperm take to meet the egg? Where does Fertilization take place?

capacitation, chemoattraction, attachment to and penetration of the zona pellucida, exocytosis of acrosomal vesicle, binding of the sperm, membrane fusion fallopian tube

Describe secretory pattern of cortisol and its importance

carried in the blood by corticosteroid binding globulin (CBG)= transcortin

describe effects of testosterone during development on the body and brain and how these are manifested

cause Wolffian ducts to transform and convert to DHT to create penis, scrotum and prostate

Describe hormonal positive feedback involved with delivery

cervical stretch-> stimulates oxytocin release-> causes uterine contractions-> push baby against cervix-> cervical stretch delivery of baby stops the cycle

What is the hypophyseal portal system and describe why its important?

connects hypothalamus to pituitary, allows for the direct transfer of hormone from one tissue to another without having to travel through systemic circulation important b/c delivers neural hormones precisely and restricts them to the pituitary

define 5α-reductase

converts testosterone to DHT

What happens to the follicle immediately after ovulation? What are the main hormone products?

corpus luteum forms, Progesterone (mainly this) and estrogen

Describe the mechanisms behind (and treatments for) iodine deficiency

cretinism, infant or child has TH deficiency, no thyroid gland, thyroid glad doesn't produce T3 and T4 or lack pendrin, or lack iodine give T4 and T3

A patient goes to his doctor for a normal check-up, and the doctor sees that he has very high levels of Na+ and Cl-. He runs some tests, and determines that: a. The patient has high blood pressure caused by underproduction of aldosterone. b. The patient has high blood pressure caused by no production of aldosterone. c. The patient has low blood pressure caused by overproduction of aldosterone. d. The patient has high blood pressure caused by overproduction of aldosterone. e. The patient has low blood pressure caused by underproduction of aldosterone.

d

Angiotensinogen is converted into angiotensin I by ________________________ a. the macula densa b. aromatase c. aldosterone d. renin angiotensin-converting enzyme

d

In spermatogenesis, meiosis results in the formation of a. One sperm cell with 23 chromosomes b. Two sperm cells with 46 chromosomes each c. Two sperm cells with 23 chromosomes each d. Four sperm cells with 23 chromosomes each e. Four sperm cells with 46 chromosomes each

d

In the male, androgens (testosterone) are made by ________________cells. a. thecal b. granulosa c. dermal d. Leydig e. Sertoli

d

JFK was often described as having a glowing perpetual tan. Now that you understand the adrenal, what is teh mechanism behind JFKs tan? a. ACTH deposits in the skin and creates dark pigment b. his low ACTH levels activate melanocytes in the skin c. his high cortisol levels activate melanocytes in the skin d. ACTH has homology with MSH and can activate melanocytes e. his melanocytes are producing less melanin

d

Which ONE of the following statements is TRUE? a. Aromatase is an enzyme acting on estradiol b. The negative feedback effect of estradiol drives the LH surge c. Progesterone causes breast development in XY "females" d. FSH and LH are secreted by the same cells e. Primordial follicles contain secondary oocytes

d

Which is the correct order of how the pineal gland receives input? a. retina, pineal gland b. retina, suprachasmatic nucleus, pineal gland c. retina, superior cervical ganglion, suprachiasmatic nucleus, pineal gland d. retina, suprachiasmatic nucleus, paraventricular nucleus, superior cervical ganglion, pineal gland e. retina, paraventricular nucleus, superior cervical ganglion, pineal gland

d

Which of the following describes the traditional signal transduction mechanism for estrogen, a steroid hormone? a. Activation of a G-protein coupled receptor b. Activation of the cAMP second messenger system c. Opening or closing of ligand-gated channels d. Altering transcription of mRNA Release of intracellular calcium stores

d

Which of the following statements is FALSE: a) Melatonin is derived from Serotonin b) the duration of melatonin release corresponds to night length c) the pineal gland is located in the epithalamus d) Melatonin is made from tyrosine e) the pineal gland is called the third eye

d

Which of the following would cause humoral stimuli of an endocrine gland. a. High follicle stimulating hormone b. Catecholamine release c. High oxytocin d. Low calcium levels e. Low Estrogen

d

All of the following are likely consequences of an exogenous administration of cortisol EXCEPT: a. Stimulation of glyconeogenesis b. Inhibition of glucose uptake in adipose tissue c. breakdown of skeletal muscle d. down-regulation of anti-inflammatory proteins e. breakdown of bone tissue

d.

Explain the consequences of Addison's disease

darker skin (hyperpigmentation), low blood pressure, weight loss, fatigue, weakness

Darcy and Paul are having difficulty conceiving. Darcy ovulates every 28 days and Paul's sperm count is normal. But, after evaluation of Paul's sperm after ejaculation, they appear to be moving sluggishly. When Paul's sperm encounter Darcy's oocyte, they appear incapable of generating an adequate acrosome reaction. Explain what likely is occurring.

decrease capacitation

What happens to the corpus luteum if fertilization does not take place?

degenerates, corpus albicans

Define spermatogonia, primary spermatocyte, secondary spermatocyte, spermatids and spermatozoa.

diploid cells that go through mitosis go through Meiosis I haploid Meiosis II haploid spermatids: product of Meiosis II (haploid) spermatozoa: sperm final result

Why is the pituitary called the master gland?

directs other organs and endocrine glands to suppress or induce hormone production

In females, the _____________________ ducts atrophy as a result of apoptosis. a. epidydimal b. chorionic c. Müllerian d. seminiferous e. Wolffian

e

What does the superior cervical ganglion (SCG) secrete and what are the target cells? a. Serotonin, Pinealocytes b. Melatonin, Suprachiasmatic nucleus c. Norepinepherine, Suprachiasmatic nucleus d. Melonin, Paraventricular nucleus e. Norepinepherine, Pinealocytes

e

Progestin is a synthetic progesterone that has anti-estrogenic effects in the endometrium. What phase of the uterine cycle is most affected by progestin treatment? a) follicular phase b) secretory phase c) luteal phase d) menstrual phase e) proliferative phase

e) proliferative phase

What are totipotent and pluripotent cells?

each cell can develop into a new individual each cell can into over 200 cell types

Primary germ layers

ectoderm, mesoderm (Gastrula), endoderm

Cervix must do this before birth

efface (thin), dilate

What is the main stimulus for the secretory phase of the endometrium? What happens during the secretory phase of the endometrium?

elevated progesterone, receptive to implantation of the blastocyst and supportive of early pregnancy

What is androgen binding protein and why is it important?

elevates testosterone conc in the testes

define aromatase

enzyme used to convert testosterone to estradiol

Acute hormone secretion (Patterns of Hormone Secretion)

epinephrine in response to stress, not released all the time

What hormone Promotes thickening of the endometrium?

estrogen

describe the roles of estrogen and dihydrotestosterone in sexual development

estrogen causes Wolffian duct regression and outer vagina along with external genitalia DHT causes development of penis, scrotum and prostate

Define the hypothalamic-pituitary-ovarian axis and its feedback loops.

estrogen exerts neg feedback on the hypothalamus and anterior pituitary except at high levels when estrogen exerts a positive feedback positive feedback triggers the LH SURGE, which triggers ovulation

Why is it that only one sperm out of the hundreds available actually enter the oocyte?

fast block: depolarization of ovum membrane slow block: intracellular incr Calcium

What are the two types of blocks to polyspermy? Describe their mechanisms

fast block: membrane depolarization slow block: Ca2+ releases by oocyte ER, destroys sperm receptors

Episodic (Cyclic) hormone secretion (Patterns of Hormone Secretion)

female reproductive hormones

define the Wolffian duct

fetal leydig cells produce testosterone which stimulates Wolffian duct differentiation, transforms into epididymis, vas deferens, seminal vesicles, ejaculatory duct

What is quickening?

first fetal movements that woman feels

define SRY gene

gene on Y chromosome and expressed in urogenital ridge is required for the formation of the testis in males

GH

general anabolic stimulant, increases release of insulin-like growth factor (IGF-I), cell growth

Describe the mechanisms behind (and treatments for) hypothyroidism and Hashimoto's disease

give T4, low in iodide in developing countries, why we have iodized salt

What cells are producing inhibin? Why is inhibin important?

granulosa cells in response to FSH, stops aromatase from making estrogen

Hormone secreted by trophoblast

hCG

Maintains corpus luteum for 2-3 months

hCG

Discuss the important features of the head, midpiece, and tail of mature spermatozoa.

head: DNA becomes highly condensed, cap/ Acrosome phase- golgi surrounds condenses nucleus forming Acrosomal cap midpiece- mitochondria tail: centriole elongates to become tail. Mito conc in 1st part of tail, sperm point tail towards center of lumen

Explain specific consequences of high ACTH and cortisol and adrenal androgen disorders.

high cortisol + high ACTH= Cushing's no cortisol and no aldosterone= Congenital Adrenal Hyperplasia (CAH) Low Cortisol/ High ACTH= Primary Adrenal Insufficiency Low Cortisol/ Low ACTH= Secondary(or tertiary) Adrenal Insufficiency

Autocrine

hormones act on same cell

What is a tropic hormone? Which hormones of the anterior pituitary are tropic?

hormones that target other endocrine glands GH (sometimes, only if going to the liver), FSH, LH, ACTH, TSH

List 3 possible ways that dysfunction of this axis can give rise to Cushings disease.

hypothelamus is insensitive to cortisol tumors in hypothamus- incr CRH tertiary Cushings tumor in AP= incr ACTH secondary Cushings Tumor in adrenal: incr cortisol primary cushings

define the Mullerian duct

in absence of Mullerian inhibiting substance (MIS/ AMH). precursor to female reproductive tract, transforms into uterus, fallopian tubes, inner vagina

How does TSH stimulate T3/T4 production?

in ant pit goes to thyroid and incr iodide transport incr thyroglubulin-> T4 and T3

Prohormone

inactive hormone precursor

Define the zona reticularis and the hormones that they produce

inner layer, androgens

Mass of cells within the blastocyst

inner mass

explain 5α-reductase deficiency

intersex, at puberty incr testosterone creates DHT so testes descend, penis enlarges, facial hair appears, voice deepens, muscles develop- appear female before puberty Large group in Dominican Republic- Guevedoces

Describe the effects of ACTH on the adrenal

it converts cholesterol to Pregnenolone wihich is used to make aldosterone, cortisol, and DHEA (androgen production)

Define the zona fasiculata and the hormones that they produce

layer between glomerulosa and reticularis, cortisol

Describe structure and function of the adrenal cortex

layer surrounding medulla, has fasiculata, reticularis, and glomerulosa make hormones

Secondary amenorrhea (loss of menstrual period) is common in female athletes due to blocked hypothalamic regulation. These women produce little, if any, estrogen (which can also cause osteoporosis). Why are such women deficient in estrogen (please explain all three tiers of the reproduction axis)? What treatment would you recommend and why?

low GnRH-> low LH & FSH in Ant Pit-> decrease folliagenesis (ovary)->low or no estrogen Supplement with estrogen

Describe how steroid hormones signal (generally).

made and carried through blood by binding globulin-> across plasma membrane and bind to a receptor

Chronic hormone secretion (Patterns of Hormone Secretion)

maintenance of relatively constant concentration of hormone, Thyroid hormone

Describe Sperm capacitation and why is it important?

occurs while migrating through female reproductive tract Cholesterol withdrawl Surface proteins redistributed Calcium influx (increases motility-> whiplashing) allows sperm to penetrate the corona radiata, contact the zona pellucida and undergo the acrosome reaction

Define the zona glomerulosa and the hormones that they produce

outer edge of adrenal gland, aldosterone

FSH

ovarian follicle development and ovulation, increases estrogen production; acts on Sertoli cells of seminiferous tubule to increase spermatogenesis

Describe ANP

peptide, Atrium of heart, stimulated by incr BP 1) Kidney, lowers renin 2) adrenal cortex, decr aldosterone 3) posterior pituitary, lowers ADH 4) vascular, incr vasodilation

Describe ANGII

peptide, incr vasoconstrict, incr aldosterone (adrenal cortex), incr ADH (post pit)

Secretes Oxytocin

posterior pituitary

What are the advantages of iodized salt?

prevent low iodine and Cretininsm

What is the difference between a primordial and a primary follicle?

primordial- oocyte and granulosa cells nucleus of oocyte, fully grown oocyte, granulosa cells and zona pellucida

What are theca cells and how are stimulated? What hormone do they produce?

produces androgen that goes to granulosa cells

Negative feedback systems

product turns off the sensor which initiated the product stimulates the sensor to incr its own production-self propagating

explain congenital adrenal hyperplasia

progesterone ->17-hydroxyprogesterone-> adrenal androgens

What is ZP3 and where is it located?

receptor on zona pellucida that sperm binds to

Describe how peptide hormones signal (generally).

receptor-> signal transduction (relay molecules)-> nucleus

Long half-life:

regulate activities that remain @ a constant rate through time. Usually lipid soluble and travel in plasma attached to proteins

paracrine signaling

release of chemical messengers

ADH

responds to osmoreceptor which senses extracellular [Na+], blood pressure regulation, incr H2O readsorption from distal tubules in kidney

What are the functions of testosterone (androgen)?

secondary sex characteristics, and making DHT via 5Alpha reductase enzyme

Preprohormone

signal sequence plus inactive precursor hormone

What is a Morula? What is a blastocyst?

small collection of cells over 100 cells; fluid center, once attaches to endometrium them referred to as embryo

What is a polar body? Where in a woman's body would you find a secondary oocyte?

small haploid cell that was created from uneven cytoplasmic cell division during meiosis is ovulated, fallopian tube?

Explain why cortisol must be converted in the kidney (recall liquorice).

so it doesn't bind to aldosterone receptor

What is the relationship between the sodium/iodide symporter and pendrin? How would inactivating mutations in either transporter alter iodide uptake?

sodium/iodide symporter: 2 Na+ with 1 I- into follicular cell Pendrin: 1 Cl- (enter follicular cell) 1 I- (enter into lumen)

What is colloid and what does it contain?

space inside follicle, contains thyroglobulin which is a precursor to thyroid hormone

What are the seminiferous tubules and what cells are located there?

sperm production, sertoli cells and germs cells

What essential role does the epididymis play?

sperm storage and maturation

What are the products of mitotic division of the primitive germ cells in the seminiferous tubules? When does mitotic division begin?

spermatocytes, at increases at puberty

What are the primitive germ cells of the epithelium of the seminiferous tubule called, and where are they located?

spermatogonia (spermatogonial stem cells, spermatocytes, spermatids, spermatozoa) seminiferous tubule

Name and describe the process during which a spermatid is converted to motile sperm

spermiogenesis 1) Golgi phase: polarity (head and tail) 2) Acrosome phase: golgi surrounds nucleus, makes cap) 3) Tail phase: centriole = tail, mitochondria condense around base of tail) 4) Maturation: gains motility Sperm now fully formed, stored in tail of epididymis

What are the two main functions of the testes

steroid hormone production Sperm production

Describe Aldosterone

steroid, adrenal cortex, target distal tubule of kidney, incr Na+ reabsorption, decr K+ reabsorption

Why would thyroxine (T4) be sufficient for treatment of the baby?

still functioning 5'-deiodinase Type I: T4->rT3- nonfunctional, limit T4 in body Type 2: T4->T3 baby's body now has T3 and T4

Describe the possible effects of ACTH (MSH) on the skin

stimulates MSH (melanocyte stimulating hormone) melanocytes and can darken skin

ACTH

stimulates cells of adrenal gland to increase steroid synthesis and secretion

PRL

stimulates differentiation of cells of mammary gland and stimulates milk synthesis

Describe steroid hormone production and storage

synthesized on demand from precursors- not stored, simple diffusion

Where are the most mature sperm concentrated in the epididymis?

tail

endocrine signaling

targets distant cell through the bloodstream

Discuss the negative feedback regulation of the hypothalamic-pitutiary-gonadal (HPG) axis in the male.

testosterone neg feedbacks posterior pituitary (FSH and LH) and hypothalamus (GnRH)

Half-life

the length of time it takes for half a dose of substance to be eliminated from circulatory system

What is fertilization?

union of sperm and egg

Oxytocin

uterine contraction, causes milk ejection in lactating females, responds to suckling reflex and estradiol

Short half-life

water-soluble hormones as proteins, epinephrine. Have a rapid onset and short duration

Broadly Describe maternal changes during pregnancy.

weight gain, incr water retention, mammary gland development