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218 Cards in this Set
- Front
- Back
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Gonads |
The primary sex organs: ovaries or testes |
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Secondary Sex Organs |
Male: ducts, glands and penis (deliver sperm) Female: uterine tubes, uterus and vagina (receive sperm and nourish fetus) |
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Secondary sex characteristics |
Pubic, armpit and facial hair, scent glands, body morphology and low voices in males |
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Mesonephric (Wolffian) Ducts |
Develop into male reproductive system Paramesonephric ducts degenerate |
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Paramesonephric (Mullerian) Ducts |
Develop into female reproductive tract Mesonephric ducts degenerate |
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SRY |
Sex-determining Region of Y gene Grows testes and secretes testosterone Degenerates mullerian ducts Without SRY, a female develops |
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Androgen Insensitivity Syndrome |
Genetically male (XY) Testosterone is secreted, but no receptors for it. No masculinizing effects occur |
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Somatic Cells |
Diploid cells. 46 chromosomes. 23 pairs. Also known as autosomes. |
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Sex Chromosomes |
Also known as Gametes. One pair of 23 chromosomes. Either X or Y. Produced by Meiosis. |
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Prophase I of Meiosis I |
DNA membrane dissolves and spindles emerge |
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Metaphase I of Meiosis I |
Homologous chromosomes line up along the center and crossing over occurs. Microtubules attach |
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Anaphase I of Meiosis I |
Each pair of homologous chromosomes are divided as they are pulled to opposite sides of the cell |
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Telophase of Meiosis I |
The cell divides resulting in 2 Haploid cells |
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Purpose of Meiosis I |
One diploid cell becomes two haploid cells |
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Tetrad |
Two homologous chromosomes are attached at a centromere, each with two sister chromatids totaling 4. |
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Purpose of Meiosis II |
To create 4 unique haploid daughter cells (gametes) from 2 haploid cells. Each gamete contains one sister chromatid instead of a whole chromosome |
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What is the vertical division of the scrotum called? |
The median septum made up of the tunica albuginea |
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What is contained in the spermatic cord? |
The ductus deferens, testicular artery and vein (Pampiniform plexus), autonomic nerves, lymphatics and the cremaster muscle |
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Pampiniform plexus |
Veins ascending near the testicular artery allow heat exchange to flow away from the testicles |
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Cremaster muscle |
An extension of the internal obliques that pull testes up as a protective reflex and to regulate temperature |
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Dartos muscle |
Smooth muscle that wrinkles the skin decreasing the surface area of the scrotum to minimize heat loss |
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Tunica Vaginalis |
The pushed out parietal peritoneum. Called serosa in adults. Creates a lubricating fluid to protect against friction |
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Cryptorchidism |
One or both testes do not descend into the scrotum. Results in sterility and increased risk of cancer. Most descend spontaneously. |
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Torsion |
Twisting of the testes or ovaries which cuts off blood supply |
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Seminiferous Tubules |
Contain sperm in all their stages of development |
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Leydig Cells |
Surround the seminiferous tubules and secrete testosterone |
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Sertoli Cells |
Also known as Sustentacular cells. Form BTB. Control or inhibit sperm production through the production of FSH and Inhibin. Produce fluid and release sperm into lumen. |
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Type A daughter cells in Spermatogenesis |
Are a product of Mitosis. Identical daughter cells. One (A) stays behind to replace parent |
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Type B daughter cells in spermatogenesis |
One daughter spermatogonium (B) crosses BTB to become a Primary spermatocyte that will undergo Meiosis and become a Secondary Spermatocyte. |
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Spermiogenesis |
Spermatid discards cytoplasm and sprouts a flagelate tail. |
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Spermiation |
Release of a sperm cell from a Sertoli cell |
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Reduction Phase |
Going from 2n to n |
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When does the centriole become the basal body? |
When the flagella is produced |
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What is contained within the acrosome? |
Hyaluronidase and Protease enzymes for penetrating the egg cell |
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What is the purpose of the midpiece of the sperm? |
It contains Mitochondria that produce ATP for flagellar movement |
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What chemical is responsible for the start of puberty? |
A surge of pituitary gonadotropins |
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When does puberty officially end? |
The first menstrual period in girls and the first ejaculation of viable sperm in boys |
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When does adolescence officially end? |
When a person attains full adult height |
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Precocious Puberty |
Early onset puberty |
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What is GnRH and where is it released? |
Gonadotropin Releasing Hormone from the Hypothalamus |
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What effect does LH have in males? |
Stimulates Leydig cells to produce Testosterone |
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What effect does FSH have in males? |
Stimulates Sertoli cells to secrete androgen-binding protein to stimulate spermatogenesis when it interacts with testosterone |
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How is Testosterone levels maintained? |
A negative feedback loop based in the hypothalamus which measures the level in the blood supply. |
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What effect does Inhibin have in males |
Slows sperm production by stimulating the anterior pituitary gland to release less FSH and LH |
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Efferent ductules |
transport sperm from rete testes to epididymus |
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Epididymus |
Site of sperm maturation and storage (1-2 months) |
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Ductus Deferens |
Passes from scrotum to seminal vesicle. Undergoes peristalsis during orgams |
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Ejaculatory Duct |
Ductus deferens + Seminal vesicle Passes through the prostate into urethra |
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Histology of Epididymus |
Pseudostratified ciliated columnar epithelium Smooth muscle |
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Histology of Ductus Deferens |
Pseudostratified columnar epithelium Thick smooth muscle |
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Direct vs Indirect Inguinal Hernia |
Direct breaks through the side of the inguinal canal and goes out the superficial ring Indirect goes in the deep ring and out the superficial ring |
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What does the membranous urethra pass through? |
The urogenital diaphragm |
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Seminal Vesicles |
Produce an alkaline viscous fluid to neutralize vaginal acid and male urethral fluid. Fluid includes: Fructose (ATP) Prostaglandins (Stimulate peristalsis in uterus) Fibrin (coagulate semen) |
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Prostate Gland |
Produces alkaline fluid that increases sperm motility and viability. Includes: Citric Acid for ATP Enzymes for decoagulation |
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Bulbourethral (Cowper's) Gland |
Secretes alkaline pre-ejaculate during arousal. Lubricates urethra. |
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What's in Semen? |
A mixture of sperm, seminal fluid (60%), prostatic fluid (10%), fructose, fibrinogen, fibrinolysis (liquefies), prostaglandins and spermine |
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Spermine |
Stabilizes sperm pH |
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Crura |
Attaches penis to hip bones and flexes during orgasm |
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What is the main erectile tissue? |
The corpus cavernosa paired muscles |
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Muscle at the base of the penis |
Ischiocavernosus bulbospongiosus |
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Definition of excitement |
Vasocongestion of genitals Myotonia - involuntary flexing of skeletal muscles Increased HR, BP and respiration |
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What nervous system response causes erection? |
Parasympathetic response secretes Nitric Oxide which vasodilates and relaxes Trabecular muscles. |
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What nervous system response causes ejaculation? |
Sympathetic response expels sperm by stimulating contractions |
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Detumescence |
When the penis becomes flaccid after ejaculation from sympathetic restriction of pudendal arteries |
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What are some physical factors that could cause erectile dysfunction? |
Diabetes, vascular or neurological disturbances, drugs (alcohol, stimulants, nicotine, antidepressants, etc.) |
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How does viagra work? |
Increases the effects of nitric oxide by causing the vasodilation of penile arteries |
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What makes up the vulva |
The vagina and external genitalia |
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4 Layers of the ovaries |
Germinal epithelium Tunica albuginea Cortex - follicle growth Medulla - blood vessels, connective tissue and lymphatics |
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4 Reproductive Ligaments and purposes |
Broad - Attaches uterus to sides of pelvic wall Round - Attaches uterus to inguinal canal Ovarian - Attaches ovaries to uterus Suspensory - Attaches uterus to the lumbar wall |
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Corona Radiata |
Granulosa cells that directly touch the egg and the zona pellucida |
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Zona Pellucida |
Clear area between oocyte and granulosa cells |
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Atresia |
The degeneration of the majority of oogonia |
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Histology of Uterine Tubes (3 Layers) |
Mucosa - ciliated columnar epithelium with secretory cells Muscularis - Circular and longitudinal (2) undergo peristalsis Serosa - outer membrane |
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Histology of cervix |
Stratified squamous (same as vagina) |
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Anteflexion |
The uterus normally projects forward and over the bladder |
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Retroflexion |
Uterus tilts slightly less forward |
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Histology of the Uterus (3 layers) |
Endometrium (inner) - simple columnar. Stratum functionalis and stratum basalis Myometrium - 3 layers of smooth muscle Perimetrium (outer) - Visceral peritoneum |
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Progression of uterine arteries |
Uterine - Arcuate - Radial - Straight - Spiral ONLY straight and spiral reach the endometrium ONLY spiral respond to progesterone |
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Hormones involved in the first half of your period |
Estrogen and FSH |
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Radical Hysterectomy |
Removes uterus, tubes, ovaries, part of the vagina, pelvic lymph nodes and supporting ligaments |
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Complete Hysterectomy |
Removes the uterus and cervix |
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Functional Cyst |
Grows each month and disappears with your cycle |
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Histology of Vagina (3 layers) |
Mucosal Layer (inner) - stratified squamous. Glycogen breakdown to produce acidity Muscularis - Thin smooth muscle Adventitia - Loose connective tissue that attaches vagina to other organs |
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Pudendum (vulva) |
Is the external genitalia including: Mons pubis Labia (majora and minora) Clitoris Bulb of vestibule (erectile tissue) |
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Cooper's (suspensory) Ligaments |
Attach breast to skin and muscle. |
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Fibrocystitis |
Cysts and thickening of alveoli. Most common cause of breast lumps. Caused by lack of progesterone or too much estrogen |
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Which hormones does the anterior pituitary produce? |
FSH and LH |
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Tanner Stages (3) |
The development of secondary sex organs Thelarche - Breasts Pubarche - Growth of pubic and armpit hair, apocrine and sebaceous glands Menarche - First menstrual period |
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Hormones secreted by the Corpus Luteum |
Progesterone - prepares uterus and mammary glands Relaxin - Facilitates implantation in the relaxed uterus Inhibin - stops release of FSH |
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Follicular (Proliferative) Phase |
First two weeks of cycle. AKA Menstrual Phase. Period occurs and endometrium is lost and replaced. Follicles grow. |
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Luteal (Secretory) Phase |
Second two weeks of cycle. Corpus Luteum increases estrogen and progesterone which thicken endometrium which is lost again if pregnancy does not occur |
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What causes the stratum functionalis to die off? |
Declining levels of progesterone cause constriction of spiral arteries in the endometrium leading to tissue death |
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Follicular Phase in Ovary |
FSH stimulates the maturation of multiple follicles and ends with ovulation |
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Proliferative Phase in Uterus |
Occurs concurrently with Follicular phase in ovaries. Endometrium thickens from increased estrogen |
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Postovulatory Phase - Uterus and Ovaries |
Last 14 days. In the Ovaries (Luteal) - Formation of corpus albicans and increase in LH and FSH With fertilization - Embryo secretes hCG to maintain corpus luteum In the Uterus (Proliferative) - Menstrual cycle With fertilization - Thickening of endometrium and formation of glands and vascularization |
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Premenstrual Dysphoric Disorder (PDD) |
More severe form of PMS dominated by mood symptoms |
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Estrogen's effect on GnRH, FSH and LH |
High: Promotes Medium: Inhibits Low: Promotes |
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Causes of Dysmenorrhea |
Uterine tumors, ovarian cysts, endometriosis, or IUD |
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Orgasmic Platform |
Outer 1/3 of vagina |
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Hormones in oral contraception |
Estrogen and Progesterone |
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Norplant Hormones |
Progestin |
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Depo-Provera Shot Hormones |
Progesterone |
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Vaginal ring |
Combination of Progestin and estrogen |
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Physiological methods of birth control |
Rhythm method - Periodic abstinence near ovulation Sympto-thermal - abstinence during ovulation signs Coitus interruptus - Withdrawal |
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Dilation and Curettage (D&C) |
Suction, saline infusion, scraping to kill embryo |
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RU 486 |
Also called Plan B or the morning after pill. Antiprogestin causes immediate menstruation |
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Most common cause of female infertility |
Pelvic inflammatory disease (PID). Other causes include ovarian disease, tubal obstruction, inadequate or excessive body fat. |
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In Vitro Fertilization |
Oocytes (from mother) removed and implanted with sperm, then replaced in uterus (of mother) |
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Embryo transfer |
Artificial insemination of DONATED oocyte and then implanted in infertile mother |
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Gamete Intrafallopian Transfer (GIFT) |
Sperm is implanted in fallopian tubes. Fertilization occurs in vivo. |
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Respiratory changes during pregnancy |
Increase in tidal volume Decrease in expiratory reserve Increase in minute respiratory volume |
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HELLP Syndrome |
Hemolysis, elevated liver enzymes, low platelets |
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Eclampsia |
Preeclampsia + proteinuria + seizures |
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Pregnancy Induced Hypertension (PIH) |
High BP Preeclampsia if proteinuria |
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Blastocyst Phase |
1-2 weeks |
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Embryo Phase |
3-8 weeks |
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Fetus Phase |
9-38 weeks |
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Human Chorionic Somatomammotropin (HCS) |
Human placental lactogen. Secreted from placenta. Decreases mother's glucose usage and increase release of fatty acids |
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Progesterone in pregnancy |
Secreted from the placenta and corpus luteum. Prevents FSH and LH from stimulating follicular development. Stops menstruation. Thickens endometrium. Develops acini in breasts |
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Hyperemesis Gravida (HG) |
Morning sickness during first few months |
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Nutrients needed by the fetus |
Protein, iron, calcium, vitamin K (hemorrhage), Folic acid (neural tube defects) and phosphates |
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Chloasma |
Mask of pregnancy. Blotchy darkening over the nose and cheeks |
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Braxton Hicks |
AKA false labor. Weak contractions that occur throughout gestation. |
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Hormonal changes near full term |
Posterior pituitary gland releases more oxytocin and uterus produces more receptors. (stimulates contractions). Fetus produces cortisol which enhances estrogen and prostaglandin secretion which both stimulate oxytocin (dilate cervix) |
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What is the difference between true and false labor? |
Both have uterine contractions, but true labor's are at regular intervals and includes cervical dilation due to the presence of prostaglandins |
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Positive feedback loop of labor |
Cervical stretch - oxytocin - uterine contraction - cervical stretch |
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What is the source of labor pains? |
Myometrial ischemia and cervical stretching |
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Early Dilation Stage |
Widening of cervical canal by thinning of the cervix, rupture of fetal membranes and loss of amniotic fluid |
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Late Dilation Stage |
Fully dilated, time to push |
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Expulsion Stage |
Time from when baby's head enters vagina until fetus is expelled |
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Placental Stage of Birth |
Contractions continue until the placenta is expelled |
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Dystocia |
Difficult labor due to fetal position or size |
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Puerperium |
First six weeks after delivery |
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Involution |
Pertaining to the shrinkage of the uterus after parturition Autolysis by lysosomal enzymes produces lochia Promoted by breast-feeding |
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Lochia |
Vaginal discharge after parturition |
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Hormones involved in lactation |
Estrogen - Stimulates duct growth Progesterone - Stimulates acini growth HPL and Prolactin - Stimulate milk production Oxytocin - Stimulates milk ejection |
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Colostrum |
Breast milk containing 1/3 less fat, thinner and contains IgA antibiotics |
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Nursing effect on ovulation |
Inhibits GnRH to reduce ovarian cycling |
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What hormone spikes during breast-feeding? |
Prolactin |
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What physiological effect causes milk ejection? |
The contraction of myoepithelial cells surrounding lactiferous gland acinus |
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Benefits of breastfeeding |
WBC - breakdown bacteria in gut, macrophages produce lysosomes, antibodies Decreased incidence of disease later in life Bonding time Child drinks what they need |
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Cystocele |
Prolapsed bladder moves into vagina |
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Rectovaginal Fistula |
A fusion and passageway created between the vagina and rectum |
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Chlamydia |
Bacteria caused. Asymptomatic. Causes infertility from scarring (PID) |
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Gonorrhea |
Bacteria caused. Discharge. Blind newborn if infected. Second most common cause of PID |
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Syphilis |
Bacteria caused. Painless sores (chancres). Affects all organs eventually including the brain (neurosyphilis) |
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Genital Herpes |
Virus caused. Incurable. Painful blisters |
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Genital Warts |
Virus caused (HPV). Associated with cervical cancer. There IS a vaccine |
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Testicular Cancer |
Most common among younger men. Problem with spermatongonia in seminiferous tubules. Becomes a mass. |
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Endometriosis |
Uterine tissue is expelled from the uterine tubes and grows elsewhere in the body. Responds to monthly hormones causing breakdown and bleeding. May lead to scarring and infertility |
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Most common male cancer |
Prostate cancer |
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Most common female cancer |
Breast cancer |
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Symptoms of Breast Cancer |
Palpable lump Skin puckering Nipple drainage Orange peel skin |
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Risk Factors of breast cancer |
Family history, aging, estrogen and progesterone exposure, BRCA 1 and BRCA 2 mutations, ionizing radiation, carcinogens, alcohol, smoking and high fat intake |
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2nd most common killer of women |
Ovarian Cancer |
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Risk factors for ovarian cancer |
Over 50, white, family history, nullparity, first pregnancy after 30, high fat, low fiber diet, low vitamin A, asbestos and talc |
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Cervical Cancer |
Squamous cell carcinoma. Change in shape of the cervix. Slow growing. Detected in Pap smears |
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Fungus that causes a yeast infection |
Candida albicans |
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Risk factors for yeast infection |
Recently on antibiotics, common in diabetics |
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Neonatal Period |
42 days after birth. 6 weeks |
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Antiperistalsis |
The sperm contain prostaglandins that stimulate peristalsis in the uterine tubes to pull sperm towards egg. |
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How is the egg pulled into the uterine tube |
Egg is pulled into uterine tube via negative pressure and cilia transport |
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How long is capacitation? |
Ten hours |
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What is the acrosomal reaction? |
ZP3 (zona pellucida) glycoproteins bind with the sperm head it triggers the release of hyaluronidase and acrosin |
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Describe the fast and slow block to polyspermy |
Fast block: Oocyte membrane depolarization (1-3 secs) Slow block: Cortical reaction. Granulosa cells release Ca+ to harden the zona pellucida (now fertilization membrane) |
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How are fraternal twins formed? |
Two eggs, two sperm |
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How are identical twins formed? |
One egg, one sperm. Cell splits but may share placenta |
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What can cause ectopic pregnancies? |
PID, multiple D&C procedures (Asherman's syndrome), tubal surgery, history of smoking (paralyzes cilia) |
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Amnion |
Purpose: Shock absorption, regulates body temp Made of: Maternal filtrate and fetal urine |
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Amniocentesis |
Taking a sample of the amniotic fluid |
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Chorion |
Becomes placenta Trophoblast + Extraembryonic mesoderm Produces hCG |
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When does organogenesis occur? |
The Embryonic period |
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When does organ maturation occur? |
The fetal period |
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Allantois |
An outpocketing of the yolk sac that later becomes the umbilical cord |
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Ectoderm gives rise to.. |
Nervous system, special sensory organs |
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Endoderm gives rise to.. |
GI tract and Lower respiratory tract |
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Mesoderm gives rise to.. |
Skin, muscle, bones, organs, blood |
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Trophoblastic Nutrition |
Fetus is nourished by the digestion of endometrial cells for the first 8 weeks |
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Placental Nutrition |
Fetus is nourished by the mother's blood stream through the placenta after 8 weeks |
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Chorionic Villi |
Extensions of cytotrophoblast into endometrium to "digest" mother's blood |
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Placental Sinus (lacunae) |
Mother's blood surrounds chorionic villi |
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Decidua Basalis |
Endometrium touching the chorionic villi. Forms maternal portion of placenta |
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Decidua Capsularis |
Opposite the placenta. Surrounds the amnion and chorion |
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Decidua Parietalis |
The endometrium of the uterus except at the point of connection to the placenta |
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Which viruses can pass through the placenta? |
HIV, rubella, measles, chickenpox, polio, encephalitis |
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Placenta Previa |
Placenta covers the cervical os. May lead to spontaneous abortion or increased maternal mortality. Sudden bright red blood in 3rd trimester |
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Placental abruption |
Small or large separation of placenta from the uterus. Causes: trauma, tobacco or alcohol use, hypertension |
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Rhogam |
Given to Rh negative mothers in case of blood mixing or trauma so that immune system does not attack possible Rh positive baby |
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Uses of ultrasound |
Determine fetal age, viability, growth, position, head size, twins, maternal abnormalities and size of pelvic outlet |
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Chorionic Villus Sampling |
Sample placenta. 1-2% mortality. Used for chromosomal analysis |
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Placental Hormones |
Relaxin - Relaxes pelvic ligaments and prevents contractions Estrogen and Progesterone - Maintain uterine lining hCS - decreases maternal glucose usage and increases protein synthesis hPL - Prepare mammary glands for lactation CRH - Produces fetal cortisol (lung maturation) |
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Corticotropin Releasing Hormone (CRH) |
Increases fetal cortisol to produce Type II Pneumocytes (secrete surfactant) for lung development. Also helps time birth |
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What could cause a false positive/negative pregnancy? |
Excess protein or blood in urine Molar pregnancy (trophoblast w/o fetus) Uterine cancer Steroids, diuretics, hormones and thyroid drugs |
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Premature infants may suffer from.. |
Respiratory distress syndrome Inability to thermoregulate Underdeveloped digestive system Immature liver leading to jaundice |
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What causes the baby to take it's first breath? |
Increased CO2 after umbilical cord is cut |
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Symptoms of fetal alcohol syndrome, smoking and x-rays |
Cardiac and CNS defects, anencephaly, cleft lip/palate, ADHD |
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Mutagen |
Any agent that alters DNA or chromosome structure |
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What is the most common genetic disorder? |
Nondisjunction which causes aneuploidy |
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Triplo-X Syndrome |
XXX makes an infertile female with mild intellectual impairment |
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Klinefelter Syndrome |
XXY - Sterile male, underdeveloped testes. Tall, feminine |
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Turner's Syndrome |
X - Sterile female. Webbed neck and no secondary sexual features |
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Trisomy-21 |
Down syndrome. Short stature, flat face, epicanthal fold on eyes, large tongue, stubby fingers and mental retardation |
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Inheritance |
Passing on a trait from one generation to the next |
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Translocation |
Crossing over of non-homologous chromosomes |
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Incomplete Dominance |
Intermediate phenotype Ex. Red + White = Pink Ex. Sickle Cell Anemia |
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Codominance |
When multiple genes are expressed equally Ex. ABO Bloodtype |
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Multiple-Allele Inheritance |
The majority of traits. A gene with more than two alternate forms |
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Polygenic Inheritance |
Majority of traits. Trait controlled by multiple alleles Ex. skin color, eye color, height |
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Pleiotropy |
One gene affects multiple phenotypic traits Ex. Albinism + crossed eyes |
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Epistasis |
One gene allows the expression of other genes Ex. Testosterone gene activates balding gene |
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Sex-linked Traits |
Genes found only on the X-chromosome. Ex. Muscular Dystrophy, color-blindness |
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X-Chromosome Inactivation |
One of the two X chromosomes in females in silenced. Typically no physical traits |
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Fragile X Syndrome |
Defective gene on X chromosome causes mental retardation |
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Leading cause of death from 18-34 |
Accidents, homicide, suicide, AIDS |
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Leading cause of death after 55 |
Heart disease, cancer, stroke, lung disease |
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Senescence |
Decreased function |
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Theories on why we age |
Free radicals damage macromolecules Collagen becomes cross-linked Limit to number of times cells can regenerate |
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Progeria |
Genetic disorder characterized by accelerated aging |
