A&P II Reproductive System
What happens during Mitosis of Spermatogenesis?
(Cloning) doubles its DNA then divides into 2 identical daughter cells Spermatagonia can undergo mitosis to produce more or can mature into a cell that will go through meiosis
What happens during Meiosis of Spermatogenesis?
(Variation by division of sex cells) Spermatocytes form spermatids.
Primary Oocyte
-Enters meiosis I -Divides to produce two haploid cells: One secondary oocyte One polar body [smaller cell, usually is insiginificant and reabsorbed, sometimes undergoes meosis] -Females are born with a set number of primary oocytes -Prim. oocyte enters meiosis during embryonic development, but stall before completing the division -At pubertu, one cell per month continues the process of cellular division to produce a gamete
Secondary Oocyte
-Enters meiosis II -Divides to produce two haploid cells: One ovum One polar body [only occurs if meosis occurs]
Hormones of Pregnancy
-Estrogens -Progesterone -HCG (Human Chorionic Gonadotropin) -HCS (Human chorionic somatomammotropin) * All primarily secreted by the placenta
Follicular phase
-From Begining of menstruation until ovulation Preovulatory Phase- End of menstruation until ovulation
The Ovarian Cycle
-Is divided into a follicular phase -And a luteal phase [what happens to the follicle after ovulation] -Process that involves the maturation of ovarian follicle and development o the female gamete -The ovarian cycle on average is about a 28 day cycle -Ovulation usually occurs on day 14
Male & Female Reproductive Duct
-Male reproductive tract is referred to as the mesonephric duct -Female reproductive tract is referred to as the paramesonephric duct (Mullerian)
Nutrition
-Placenta stores nutrients -Demands Protein, Iron, Calcium, phosphates -Vitamin K -Vitamin D -Folic Acid
Sex Determination in Humans # Chromosomes
-Primarily determined by the presence or absence of a Y chromosome -Chromosomes are composed of DNA and proteins -In humans, most normal somatic cells have 46 chromosomes or 23 pairs of chromosomes -Of the 23 pairs, 22 are referred to as autosomes -The 23rd pair is referred to as sex chromosomes -There are two types of sex chromosomes: X and Y -Females have two copies of the X chromosome and males have an X chromosome and a Y chromosome
Female Reproductive System: Functions
-Produce hormones -Produce gametes: ova -Protect, support and nourish a developing embryo -Nourish newborn infant
Bacterial STD's
1. Chlamydia - Urethral Discharge & testicular pain 2. Gonorrhea - pain and pus discharge 3. Syphilis - hard lesions at site of infection
Female External Genitalia (Vulva or Pudendum)
1. Clitoris 2. Labia Minora 3. Labia Majora
3 Stages of Labor
1. Dilation 2. Expulsion 3. Placental Stage
2 Stages of Ejaculation
1. Emission 2. Explusion
what are the Phases of Sexual Response
1. Excitement 2. Plateau 3. Orgasm 4. Resolution
Ovarian Cycle
1. Follicular Phase 2. Ovulation 3. Luteal Phase (post ovulatory)
Viral STD's
1. Genital Herpes -Blisters & Pain 2. Genital Warts -Warts on perineal region 3. Hepatitis B & C - Inflammatory Liver Disease
Female Internal Genitalia
1. Ovaries 2. Uterine Tubes 3. Uterus 4. Vagina
External Male Genitalia
1. Penis 2. Scrotum
3 layers the Uterine wall consists of?
1. Perimetrium (external) 2. Myometrium (mid layer) 3.Endometrium (internal)
What are the 3 accessory glands of the Male Reproductive System?
1. Seminal vesicles 2. Prostate Gland 3. Bulbourethral glands.
what are the steps of oogenesis?
1. formation of primary, secondary, and tertiary follicles 2. ovulation 3. formation and degeneration of the corpus luteum
When does sexual differentiation begin?
12 weeks of gestation ; gonads develop at 5-6 wks as gonadal ridges
How many ml of semen are ejaculated?
2- 5 ml.
Haploid Cells
A cell containing only one set of chromosomes.
Luteinizing Hormone
A protein hormone that stimulates ovulation in females and androgen production in males.
Spermatogonium
A spermatogonium is cell containing 2 sets of chromosomes that will divide to give rise to diploid primary spermatocytes
What is the Mesovarium?
Ancored to broad ligament
What is the Suspensory Ligament?
Attached to pelvis wall
What is Breast Cancer?
Cancer that usually arises from the epithelial cells of small ducts.
What do Sex Hormones play roles in?
Development and function of the reproductive organs, sexual behavior and drives, growth and development of many other organs and tissues.
What are the risk factors of Breast Cancer?
Early onset of mestruation and late menopause, no pregnancies or first pregnancy late in life, family history of breast cancer.
What do the accessory glands do?
Empty secretions into the ducts during ejaculation.
Sexual Cycle
Events that recur every month when pregnancy does not intervene -Average 28 days -Begins with 2 week follucular phase -Menstruation first 3-5 days of cycle -Ovulation ~day 14
What are the ovaries?
Female Primary Sex Organs (gonads)
What do Ovaries Secrete?
Female sex hormones, estrogen and progesterone.
Development of External Genitalia
Gential Tubercle- Becomes (glans penis) or (glans clitoris) Urogenital Folds (encloses urethra in male) or (forms Labia minors) Labioscrotal Folds- Become (scrotum) or (Labia Majora)
What does the Hypothalamus release?
Gonadotropin releasing hormone (GnRH).
What are the primary sex organs?
Gonads: Testes(male), and ovaries(female).
Mammary Gland Development
High estrogen level in pregnancy causes the ducts to grow and branch extensively
What is Spermatogensis?
Sequence of events that produces production of sperm in the seminiferous tubules of the testes. Spermatids into spermatozoa
What do Gonads produce?
Sex cells (gametes)
SRY gene
Sex determining Region of Y chromosome; in males TDF initiates development of testes and stimulates mesonephric ducts to develop into the male anatomy
Involution
Shrinkage of the uterus breast feeding promotes this
Colostrum
Similar to break milk but contains less fat 1-3 days days after birth
What encloses nerve fibers, blood vessels, and lymphatics that supply the testes?
Spermatic cord.
What do Gonads secrete?
Steroid sex hormones - Androgen's (males), Estrogen's and Progesterone (females).
What is the Broad Ligament?
Supports the uterine tubes, uterus, and vagina; also contains the suspensory ligament and mesovarium.
What does GnRH stimulate?
The anterior pituitary to secrete FSH and LH.
Puerperium
The first 6 weeks after birth
Female Puberty
Thelarche - Breast development Pubarche - Pubic and axillary Hair Menarche - First menstrual period
How are sperm delivered?
Through a system of spermatic ducts: Epididymis, ductus deferens ejaculatory duct, and the urethra.
Tenting effect
Uterus stands nearly verticle (plateau phase)
What does the Cervical Canal Communicate with?
Vagina via the external OS, Uterine body via the internal OS.
What is Infertility?
When sperm count falls below 20 million sperm/ml.
Diploid
cell or organism having two sets of chromosomes or twice the haploid number
Andropause
the decrease of the male hormone testosterone
Spermiogenesis
the maturation of the spermatids into spermatozoa ; discarding excess cytoplasm and growing tails
Oogenesis
the meiosis process that forms ova -Begins before birth -Stalls at birth and then some cells re-enter process each month at puberty -Process is not completed unless fertilization occurs -Formed at ovarian follicles
Counter current heat exchange
warm arterial blood would heat the testis and inhibit sperm production- without pampiniform plexus Must be held at 35 degrees C
Embryo
when the three primary germ layers have formed
when does menstrual activity begin?
menarche (the first uterine cycle) Ends with menopause
What is the Primordial Follicle?
follicle cell + oocyte.
What does Inhibin do?
Inhibits the release of FSH and GnRH.
what is milk production called?
Lactation
Follicle Stimulating Hormone
MEN: stimulates sperm production WOMEN: initiates growth of ovarian follicles each month and stimulates ovulation
What do the Cervical Glands secrete?
Mucus that blocks sperm entry except during midcycle.
MIH
Mullerian-Inhibiting Factor; secreted by testes causing degeneration of the paramesonephric ducts
What is Menopause?
Occurs when menses have creased for an entire year, no equivalent in males.
What are Interstitial (Leydig) cells?
Outside the seminiferous tubules that produce androgens(testosterone)
What are Ovaries held in place by?
Ovarian ligament, suspensory ligament, and mesovarium.
Gestation
Pregnancy -Average of 266 Days from conception to birth
What are the stages of development of a Follicle?
Primordial Follicle, Primary Follicle
what stimulates milk production?
Prolactin
How is Breast Cancer Treated?
Radiation, chemotherapy, and surgery followed by irradiation and chemotherapy.
Ovulation
Rupture of mature follicle and release of its egg -takes 2-3 minutes
% Accessory Glands produce?
Seminal Vesicles = 60% semen Prostate = 30% semen spermatic duct secretions = 10% Bulbo = used to lubricate Glans Penis
What are Sperm conveyed through?
Seminiferous tubules, epididymis.
Blood-Testis Barrier
Separates Sperm from immune system Prevents antibodies and other large molecules in the blood from getting to germ cells
Reproductive Cycle
Sequence of events from fertilization to giving birth -started by FSH which stimulates the maturation of follicle in the ovary -Ovulation is triggered by mid-cycle surge in LH -Follicular cells secrete estrogen and progesterone
Zygote
a fertilized egg is called a/an __ when the chromosomes of both parents have mingled to form a diploid set.
what does secretion of GnRH trigger?
a rise in FSH and LH production, and beginning of another cycle
What triggers the secretion of GnRH?
decline in progesterone and estrogen
What divides the testis?
lobules, each containing 1 - 4 seminiferous tubules.
Homologous
same evolutionary origin but not necessarily the same function Penis as to clitoris Scrotum as to Labia Majora