FInal Exam Flashcards
Endocrine and Reproductive
Gametes (sperm and egg) are formed by
testis and ovaries
Fertilization produces one cell ______ with one set of chromosomes from each parent
Zygotes
Gonads produce ____ and secrete
gametes and secrete sex hormones
List the different structures in the male reproductive system
- Testis: sperm formation
- Epidiymis: sperm maturation
- Vas (ductus) deferens: sperm duct
- Seminal vesicle: semen
- Prostate: prostatic fluid; semen
- Urethra: urine
- Scrotum: cools testis
- Penis
______ is a sac of loose skin, fascia and SM divided into two pouches by a septum. It is involved in temperature regulation of the testes
Scrotum
- sperm survive: 2-3o lower temp than core body temp
- Muscle: elevates testes on exposure to cold and arousal
______ are paired, oval glands measuring 2in by 1 inch. They are surrounded by a dense white capsule
Testes
- Septa: 200-300 compartments (lobules)
- Lobules: filled with 2 or 3 semniferous tubules (sperm formation)
Inside the testis are specific cells located either between the lobules, or inside the semniferous tubules (within lobules). What are these cells?
- Leydog: Cells in interstitial space between lobules (testosterone);
- Sertoli: inside the semniferous tubules (in lobules)
Semniferous tubules contain
- sperm forming cells
- Sertoli (supporting cells)
- Interstitial cells in between tubules secrete testosterone
Sertoli cells extend from the basement membrane to the lumen inside Semnifrerous tubules. What are the functions of these cells?
- Androgen binding protein
- -bind testosterone (Leydig cells)
- -influences dev. of male gonads - Inhibin (slow sperm production)
- dec. testosterone - blood-testis barrier
- supports developing sperm
- secrete fluid and controls sperm release /movement into lumen
Spermatogenesis: Sperm forming cells go through 2 meiotic divisions. Describe the steps
- Mitosis
- spermatogonium (2n) - Primary spermatocyte (2n)
- Meiosis I
- 2 secondary spermatocytes (1n) - Meiosis II
- 4 spermatids
- 1n - Sperm
Sperm are adapted for reaching and fertilizing the egg. Describe sperm morphology
- Head:
- -DNA, nucleus, acrosomes with enzymes - Midpiece: mitochondria
- Tail: flagella
* final maturation: epidiymus; regulated by testosterone
Describe hormonal control of male physiology
- GnRH (Hypothalamus)
- FSH and LH (Ant. pit.)
- FSH – Sertoli cells secrete androgen binding protein and inhibin
- -conversion of cholesterol to pregnenolone - LH – Leydig (interstitial) to secrete testosterone
* ABP and testosterone inc. spermatogenesis
* Regulation: Neg. feedback by inc. testosterone and inhibin
There are three main exocrine glands in the male reproductive system: Seminal vesicles, Prostate, and Cowper’s glands (bulbourethral).
Describe seminal vesicles
60% of clear, alkaline seminal fluid
major secretions fructose (nutrition) and prostaglandins (passage of semen)
There are three main exocrine glands in the male reproductive system: Seminal vesicles, Prostate, and Cowper’s glands (bulbourethral).
Describe prostate gland secretions
30% of milky, slightly acidic
*antibiotics
Semen: fibrinogen, fibrinolysin
Semen is a mixture of
fluid + seminal fluid
Normal sperm count: 50 to 150 million/mL
Erection is sexual stimulation caused by _______ nervous system
*point n shoot
Parasympathetic
- arterioles dilate: supply arterioles
- blood enters penis - compress veinous outflow
- blood sinuses of penis engorge with blood
Emission is the next step following erection. It stops at the ejaculatory duct (before ejaculation).
During emission, Muscle contractions ____ the sphincter at the base of the bladder.
Fluids are propelled through the ____, _____ and _____ to the bulb of the penis
Muscle contractions: close sphincter
Fluids propelled: ductus deferens, seminal vesicle and ejaculatory ducts into bulb
Prostatic fluid: secreted into urethra
*controlled by sympathetic
EJaculation is the final step in male sex reflex. Ejaculation is controlled by ______ nervous system.
Sympathetic
-skeletal muscle (bulbospong…) squeeze semen out through urethra
Erectile dysfunction
unable to have an erection
-viagra (vasodilator)
Determine between genetic sex, gonadal sex and phenotypic sex
- Genetic sex: determine by sperm (XX, XY)
- Gonadal sex: testis vs. ovary
Males: testis determining factor - Sertoli and Leydig cells produce anti-mullerian hormone and testosterone (respectively)
Females: absence of testis determining, anti-mullerian and testosterone forms female
- Phenotypic sex: gential tract, external genitalia
List the external parts of the female reproductive system
Externa:
- Vulva:
- pubis
- labia majora
- labia minora
- clitoris - Vestibule
- urethral opening
List the internal reproductive structures in females
Internal:
- Ovaries: egg (oocyte) production and hormones
- Uterine tubes: transport eggs
- uterus: fetal development
- Vagina (birth canal)
- External genitalia (vulva)
- Mammary glands: milk
True/False: Before birth females already produce oogonia
True
Puberty: 400,000
Geriatric/Menopause: death
List the steps of sperm development
- germ cell
- spermatogonium
DNA replication/S phase - Primary spermatocyte
Meiosis I - Secondary spermatocyte
Meiosis II - Spermatid
Spermiogenesis (lose cytosplasm, gain flagella, acrosome) - Spermatozoa
capacitation - increase motility, change in cell surface proteins and acrosome
List the steps in gestation
1. germ cell gestation 2. Oogonium S phase/DNA rep. 3. Primary oocyte meiosis I meiotic arrest until LH, FSH surge at puberty 4. Secondary oocyte + 1 polar body (may degenerate) Meiosis II Meiosis II arrest until fertilization 5. Ovum + up to 3 polar bodies
List the steps in gestation
- germ cell
gestation - Oogonium
S phase/DNA rep.
(Mitosis) - Primary oocyte
meiosis I
meiotic arrest until LH, FSH surge at puberty - Secondary oocyte + 1 polar body (may degenerate)
Meiosis II (metaphase II)
Meiosis II arrest until fertilization - Ovum (graafian follicle) + up to 3 polar bodies
* longest stage between prophase I and metaphase II
* eggs contained in follicles
FSH acts mainly on
granulosa cells
-aromatase: converts androgens from theca to estrogen
granulosa cells (inner) and theca (outer) cells surround the oocyte and secrete mainly
estrogen
- growth/repair of uterine lining
- regulate female cycle
- sex characteristics
- maintain bone and muscle
A mature, graafian follicle reases an oocyte each month during
ovulation
Oocytes develop within
follicles
List the stages of follicular development
- Primordial follicle: single layer of sq. cells around oocyte
- Primary follicle:
- layers of cuboidal granulosa cells around oocyte
- -secrete estrogens - Secondary follicle
- antral cavity forms
- granulosa cells
- theca cells - Graafian follicle
- follicle mature
- ready to ovulate oocyte
* *antrum
* *theca and granulosa - Ovulation
- follicle ruptures releasing oocyte
After ovulation, the empty follicle becomes the Corpus luteum secretes:
- Progesterone – completes the preparation of uterine lining
- Estrogens – work with progesterone
- Relaxin – relaxes uterine muscles and pubic symphysis
- Inhibin – decreases secretion of FSH and LH
When the egg is released, it enters the fimbria end of the fallopian tube.
Describe anatomy of the uterine/fallopian tubes?
-extends from ovary to uterus
- enters infundibulum (fimbraie)
- -cilia sweep - ampulla (central region)
- site of fertilization
- -24 hrs/after ovulation - Isthmus: narrowest portion joins uterus
* zygote reaches uterus about 7 days after ovulation
The female reproductive cycle is controlled by monthly hormonal cycle from the hypothalamus, anterior pituitary and ovary.
List the two cycles
- Ovarian cycle:
- changes in ovary during and after maturation of the follicle and oocyte - Uterine cycle (menstrual)
- prep. uterus to receive fertilized ovum
*if implantation does not occur, functional layer of endometrium is shed during menstruation
- If implantation occurs: continue progesterone
- -zygote release hcG
Non-classical endocrine organs
Heart, Skin
Endocrine system: True/False: Glands that work together to maintain homeostasis
True
______ is a signalling molecule that is released into the bloodstream and modulates an aspect of physiology from a distant location
Hormone
Protein/Peptide hormones
water soluble
- pre-prohormone form in ER
- cleaved to pro-hormone
- cleaved in TGolgi
- hormone packaged into vesicles
ex: oxytocin, all hormones of hypothalamus and ant. pituitary
Steroid hormones
lipid soluble
cholesterl precursor
ex: testosterone, progesterone
- reproductive tract and adrenal cortex
Amine hormones
water soluble
Made from tyrosine
ex: norepinephrine, thyroid
Which two hormones require carrier proteins?
Steroid hormones and thyroid hormone
Hormone effects are mainly due to ____
receptor
3 requirements for hormone receptor:
- high affinity
- high specificity
- signal amplification within the target cell
Types of Hormone receptors
- GPCR (Gs, Gi, Gq)
- Steroid hormone receptors (nucleus)
- Guanylyl cyclase (cGMP)
- Receptor tyrosine kinase (autophosphorylation)
- Tyrosine-kinase associated receptor
(linked to tyrosine kinase that can phosphorylate)
Insulin binds what receptors?
Receptor tyrosine kinase
Modulation of hormones
- positive FB (oxytocin)
- negative FB
- up/downregulate receptors
- change gene expression
- carrier proteins (steroie/thyroid)
How does the Hypothalamus communicate with the anterior pituitary?
- Anterior pituitary
- -hypothalamohypophyseal portal system
How does the Hypothalamus communicate with the posterior pituitary?
*Hormones synthesized in hypothalamus; stored in Herring bodies in posterior pituitary
- Supraoptic nucleus (ADH)
- Paraventricular nucleus (oxytocin)
Dopamine inhibits _______
prolactin
TRH stimulates
prolactin and TSH
Somatostatin inhibits
GI system, insulin, glucagon, GH
*octreotide (analog) used for acromegaly; vasoconstrictor
Melanocyte Stimulating Hormone is produced by
Intermediate pituitary/anterior pituitary
FSH acts on ______
Males: Sertoli cells
- sperm production
- inhibin
- androgen binding protein
- anti-mullerian hormone
Females: Granulosa cells
–convert androgens to estradiol
(aromatase)
LH acts on _____
Males: Leydig cells
- -testosterone
- -androstenedione, DHEA
Females: Theca interna
–androgens
ACTH acts on the ______
ZF and ZR of adrenal cortex
The zona glomerulosa of the adrenal cortex is regulated by the
Renin-angiotensin-aldosterone system
*not affected by pituitary adenoma
Prolactin acts on the mammary gland and the hypothalamus to stimulate milk production. What does it inhibit?
GnRH
Anti-psychotics have what effect on dopamine?
block dopamine – inc. prolactin and dec. GnRH
GH acts on the liver to increase ______ which causes cellular growth
IGF-1
- muscles, bones,
- alters blood glucose
- high GH dec. tissue sensitivity to insulin
High blood glucose level has what effect on growth hormone?
Inhibits GH
GH-secreting pituitary adenoma can cause
Adults: acromegaly
Kids: Gigantism
Melanocyte stimulating hormone (M SH) is produced from the precursor molecule
POMC
- stimulates melanocytes
- melanin
POMC is synthesized in the _______ with at least 4 different cleavage sites. Where are these sites?
Synthesis: anterior pituitary
Cleavage: ACTH, B-endorphin, enkaphilin, MSH
Oxytocin (post. pituitary) acts on the uterus and mammary glands to cause
contractions and milk let down
ADH acts on ____ receptors in SM cells and on _____ receptors on principal cells of CD.
SM cells: V1
- -vasoconstriction
- -Gq (IP3)
CD: V2
–aquaporins to cell membrane
SIADH occurs from hypersecretion of ADH. What results?
- SSRI’s
- Carbemazepine
- Small cell carcinoma
-Urine is concentrated
-Hyponatremia
(<125mEq)
-Dangerous and dilutional
(retain too much fluid)
*personality changes, seizures, cerebral edema
Diabetes insipidus is the opposite of SIADH due to low levels of ADH. What happens in DI
excessive loss of diluted urine (lose too much fluid)
- hypernatremia
- psychogenic (mind), central (lack of ADH; idiopathic; trauma) nephrogenic (ADH receptor issue; drug-induced; Lithium)
ANP in the heart causes ______ of Na+
inhibition of Na2+ reabsorption
*vasodilator
Classification of Endocrine disorders occurs by
Location
Primary: organ
Secondary: anterior pituitary
Tertiary: Hypothalamus
True/False: Negative feedback axis describes that the final hormone or hormones produced at the level of the pituitary being able to inhibit additional further release of hormones from the Hypothalamus/pituitary
True
The Hypothalamic-Pituitary - Adrenal (HPA) Axis involves signalling from the hypothalamus that results in Cortisol release from the adrenal cortex. Disruption of the HPA axis can result in Cushing Syndrome
Describe Cushing Syndrome
High Cortisol levels in blood – inhibit CRH and ACTH
Loss of ACTH from anterior pituitary
Atrophy of adrenal glands
Symptoms: hypertension (alpha-1 receptors); immunosuppression
Addison’s disease is Adrenal destruction that results in
low cortisol, low aldosterone
- autoimmune
- no negative feedback
- high CRH, ACTH
- Crisis!
- Hyponatremia, hypglycemia, hyperpigmentation (gums, palmar surface)
Cosyntropin Stimulation test
distinguishes whether low cortisol is primary (adrenal gland) or secondary (ant. pituitary)
- Primary: Low cortisol, high ACTH
- Secondary/Tertiary: Low cortisol, low ACTH
True/False: Klinefelter’s syndrome
(47, XXY) is inherited disorder of males in which males have an extra X and don’t develop normal sexual characteristics
- -dec. testes
- -inc. GnRH
Hypothalamic - Pituitary Axis in the Liver Muscle involves GH and IGF-1 release. What inhibits GH?
Somatostatin
Insulin is secreted from the endocrine pancreas Beta cells along with C-peptide. It is the major anabolic hormone of the body.
What are its functions?
- dec. blood glucose (GLUT-4; SK and adipose)
- dec. blood aa’s
- dec. blood fa’s
- inc. K+ uptake
(inc. lipogenesis; glycolysis; protein synthesis)
List the counter-regulatory hormones of Insulin
Glucagon
GH
Cortisol
Epinephrine
Diabetes Mellitus Types
- Type I
- -Type IV hypersensitivity
- -destroy beta cells
*DKA
- Type II
- -receptor downregulation
- -end organ resistance - Gestational
- -pregnancy
- -high blood glucose crosses placenta
- -produce insulin
* hypoglycemia eventually
Effects of T3
6 B’s
- brain maturation
- bone growth (w/GH)
- B-adrenergic (inc. beta receptors in heart)
* beta blockers - Basal metabolic rate
- blood sugar
- break down lipids
TSH binds, initiating formation of T3, T4. What pathway does it use?
Gs, GPCR/cAMP
5-deiodinase converts ____ to _____ in peripheral target tissues.
T4 to T3
True/False: Free t3/T4 are the only ones that perform negative feedback
True
Hyperthyroidism is caused by high thyroid (T3/T4) and low TSH.
What is the most common disease of hyperthyroidism?
Graves disease
TSH Ab’s that act like TSH
- pre-tibial myxedema
- opthalmopathy
Hypothyroidism results from low thyroid hormone (T3/T4) but high TSH.
What is a common disese of hypothyroidism?
Hashimoto’s thyroiditis
- autoimmune destruction
- TPO antibodies
Chief cells of the parathyroid hormone secrete
PTH
–inc. serum calcium
Parafollicular C cells of Thyroid gland secrete
Calcitonin
-reduce calcium serum
PTH functions
- inc. bone resorption of ______ and ______
- inc. kidney reabsorption of Ca2+ in _______
- dec. reabsorption of phosphate in ______
- inc. Vit. D3 (calcitriol) production in ______
- Ca2+ and PO4
- RANKL (osteoblasts)
- RANK (osteoclasts) - Reabsorbs Calcium at DCT
- Trashes phosphate at PCT
- Vit. D3 at PCT
- -activates 1-alpha hydroxylase
High Calcium levels results in what actions?
- Calcium sensing receptors
- Vit. D. inhibits PTH
(mRNA level) - Calcitonin (parafollicular cells of thyroid)
Forms of Plasma Calcium
- bound to albumin
- complexed w/citrate and phosphate
- free ions
- free ions = active
- inc. pH = inc. affinity of albumin for Ca2+
True/False: Hypocalcemia makes neurons more excitable
True
Layers of Adrenal Cortex
“The deeper you go, the sweeter it gets….salt, sugar, sex. “
- Z. glomerulosa
- -Aldosterone - Z. fasciculata
- -Cortisol - Z. reticularis
- -weak androgens (precursors)
- -DHEA/ androstenedione
The female reproductive cycle is controlled by what hormones?
GnRH: hypothalamus
FSH and LH: Ant. Pit.
FSH/LH: target ovaries and drive ovarian cycle
Estrogen & progesterone: drive uterine cycle
List the phases of the Ovarian Cycle
- Follicular phase
(inc. estrogen)
- FSH stimulates follicle growth
- Growth into Graafian
- Granulosa cells: estrogen and inhibin
- inhibition of FSH
*estrogen inc. LH
- Ovulation
- -LH surge
- -rupture of Graafian and release oocyte
- -uterine tube - Luteal Phase
- -Corpus luteum (via LH)
- -Progesterone, some estrogen
- -prepares endometrium
List the phases of the Uterine Cycle
- Proliferative phase
- -rising estrogen levels
- -develop uterine walls
- -endometrial thickening - Secretory phase
- -Corpus luteum secretes progesterone
- -inc. thickening of functional layer
- -blood supply
- -glands - Menstruation phase
- -dec. progesterone
- -discharge of functional layer
- -beginning of next cycle
What happens to the corpus luteum if fertilization does not occur?
- atrophy – corpus albicans
- progesterne and estrogen levels decline
- functional layer shed (1st five days)
*inhibition of LH, FSH, and GnRH is lifted
The ______ is the site of menstruation and development of the fetus
Uterus
-fundus, body and cervix
List the layers of the Uterus
- Endometrium
- simple columnar
- Stroma
A. functional layer
B. Basal layer
- Myometrium
- 3 layers SM - Perimetrieum
- Visceral peritoneum
The ______ is a 4 inch long, fibromuscular organ ending at the cervix. It acts as the passageway for birth, menstrual flow and intercourse.
Vagina
- between urinary bladder and rectum
- orifice partially closed w/ hymen
The ________ are modified sweat glands that produce milk (lactate). The amount of adipose determines the size of the breast.
Mammary glands
Milk-secreting mammary glands alveoli open by _______ ducts at the nipple
lactiferous ducts
*areola: pigmented area around nipple
The breasts are suspended from deep fascia of the pectroal muscles via the _____ ligaments
Suspensory (cooper’s) ligaments
- _______ develop the ducts system in the breasts
- develop the milk-secreting glands which are called alveoli
- _______ stimulates milk synthesis in the alveoli
- ______ stimulates milk ejection from the alveoli
- Estrogens
- Progesterone
- Prolactin
- Oxytocin
What stimulates milk ejection?
- Nursing, suckiling, crying releases oxytocin
- SM of alveoli contract
- lactiferous ducts — lactiferous sinuses – nipple
-sensory impulses from nipple
- positive feedback
- suppresses ovulation
What happens to the corpus luteum if fertilization occurs?
- embryo implants in endometrium
- Progesterone levels maintained
- -dec. LH - hcG (embryo; outer part of blastocyst)
- -similar to LH
After about 3-4 months of pregnancy, the corpus luteum degenerates. What takes over production estrogen and progesterone?
Placenta
*progesterone: inhibits prolactin until baby is delivered
Labor should normally occur at 40 weeks of gestation. It is divided into 3 stages:
- 1st stage (3-24 hrs)
- -contractions (oxytocin; progesterone)
- -until full cervical dilation (8-10cm)
- -longest - 2nd stage (30-120min)
- -full cervical dilatation to birth
- -nulliparous: 2 hours
- -multiparous: 1 hour - 3rd stage (15-30 min)
- -delivery of placenta
During the 1st phase of labor Relaxin is released. What is the function of relaxin?
- soften CT
- ease passage of baby
During lactation:
- _____- Stimulates duct growth
- ______ - Promotes lobule growth
- __________ - Stimulate the synthesis of enzymes necessary for milk production
- Oestrogen
- Progesterone
- Prolactin & Human Chorionic Somatomammotropin
Suckling stimulates milk production via the release of ______ from ant. pit.
Milk is ejected via contraction of myoepithelial cells and release of ______ from post. pit
Milk production: PRL
Milk ejection: Oxytocin
PRL: contraceptive role
List methods of contraception
- abstinence
- vasectomy
- -vas deferens - tubule ligation
- -uterine tubes - birth control pills
- IUD’s
- cervix - Condom
- Diaphragm
- Withdrawal
- Rhythm method
Describe the process of fertilization
- acrosome
- attach to corona radiata (outer coating of ovum)
- acrosin - hydrolysis reaction
- reach inner coating (zona pellucida) - 1 sperm penetrates
- -fuses w/ cell membrane - Rapid depolarization
The following symptoms describe:
HTN, hypokalemia, Metabolic alkalosis (loss of H+ ions), hypernatremi
Primary hyperaldosteronism
*adrenal adenoma
Aldosterone acts on the _____ to reabsorb Na and water (inc. blood volume and pressure)
Collecting duct
*secrete K+ and H+
Cortisol:
BIG FIB
inhibits phospholipase A2
inhibits WBC adhesion
blocks IL-2
