Reproductive System Structures

• Reproductive fitness is not essential for an individual's survival, but rather for the continuation of the human species.
• It influences other systems within the body.
• Reproductive organs in both sexes produce and store specialized reproductive cells and secrete hormones essential for normal sexual function.

Structures of the Reproductive System

• The reproductive system ensures the existence of the human species.
• Gonads produce reproductive cells known as gametes, as well as hormones.
• Ducts receive and transport gametes.
• Accessory glands secrete fluids into ducts.
• Perineal structures are collectively known as external genitalia.
• The reproductive tract includes chambers and passageways connecting ducts to the body's exterior.
• Male and female reproductive systems differ functionally.
• Females produce one gamete per month and retain/nurture the zygote.
• Males produce large quantities of gametes (half a billion sperm per day).
• The testes (male gonads) secrete androgens like testosterone and produce sperm.
• The ovaries (female gonads) release one immature oocyte per month and produce hormones.
• Uterine tubes carry oocytes to the uterus for potential fertilization.
• The uterus encloses and supports the developing embryo.
• The vagina connects the uterus to the exterior.

Male Reproductive Structures: Sperm Pathway

• Sperm travels a specific route: testis, epididymis, ductus deferens, ejaculatory duct, and urethra.
• Accessory glands, including the seminal glands, prostate, and bulbo-urethral glands, secrete fluids into the duct system.
• Testes are 5 cm long, 3 cm wide, 2.5 cm thick, and weigh 10–15 g, hanging in the scrotum.
• The scrotum is a fleshy pouch enclosing the testes, suspended inferior to the perineum, anterior to the anus, and posterior to the penis base.
• Spermatic cords extend between the abdominopelvic cavity and testes, containing fascia, muscle layers, ductus deferens, blood vessels, nerves, and lymphatic vessels.
• These cords begin at the inguinal canal entrance, which is a passageway through abdominal musculature.
• They then descend into the scrotum.
• Blood vessels of the testes include the deferential and testicular arteries, along with the pampiniform plexus of the testicular vein.
• Testes also have branches of the genitofemoral nerve from the lumbar plexus.
• Inguinal hernias involve visceral tissue protrusions into the inguinal canal and are common in males due to the spermatic cord creating a weak point in the abdominal wall.
• The scrotum, divided by the raphe, contains separate scrotal cavities for each testis.
• The tunica vaginalis, a serous membrane lining the scrotal cavity, reduces friction with parietal (outer) and visceral (inner) layers.
• The dartos muscle, in the dermis of the scrotum, causes wrinkling of the scrotal surface.
• The cremaster muscle, a deep skeletal muscle, tenses the scrotum and pulls testes closer to the body due to sexual arousal or decreased temperature.
• Normal sperm development requires temperatures 1.1°C lower than body temperature, achieved through muscle relaxation or contraction that moves the testes.
• The tunica albuginea is deep to the tunica vaginalis.
• It consists of a dense connective tissue layer rich in collagen fibers which that supports blood and lymphatic vessels and efferent ductules of the testes
• Septa subdivide each testis into lobules containing seminiferous tubules.
• Lobules contain about 800 slender and tightly coiled seminiferous tubules which are the location of sperm production.
• Each is about 80 cm long, nearly one-half mile in each testis, and connects to the rete testis, an interconnected network of straight tubules.
• Efferent ductules connect the rete testis to the epididymis.
• Connective tissue capsules surround the seminiferous tubules, with areolar tissue filling spaces between them.
• Large interstitial endocrine cells (Leydig cells) produce androgens, are found here and testosterone is the most important androgen.
• Testes produce immobile sperm that other reproductive structures then mature, nourish, store, and transport.
• The immobile sperm is moved by cilia lining the efferent ductules then traveling into the epididymis.
• The epididymis marks the start of the male reproductive tract with a coiled tube almost 7 m long and is bound to the posterior border of each testis
• The epididymis has a head, body, and tail.
• The head is the largest part and receives sperm from efferent ductules.
• The body is on the posterior surface of testis, and
• The tail begins near inferior border of testis, ascends to connect with ductus deferens, and is the primary storage location of sperm.
• The epididymis monitors and adjusts fluid composition from seminiferous tubules, recycles damaged sperm and stores/protects sperm.
• The ductus deferens (vas deferens), 40-45 cm long forming part of the spermatic cord, it starts at the tail of epididymis.
• Ascending through the inguinal canal, it curves inferiorly along the urinary bladder and its lumen enlarges into the ampulla.
• This wall has a thick layer of smooth muscle, lined by pseudostratified ciliated columnar epithelium that propels sperm and fluid via peristaltic contractions..
• It can store sperm for months in an inactive, low metabolic state.
• The male urethra functions for both urinary/reproductive systems and extends 18–20 cm from urinary bladder to tip of penis, divided into three regions: prostatic, membranous, and spongy.
• Male Accessory glands produce the fluid component of semen with a mixture of secretions and unique biochemical characteristics including the seminal glands, prostate, and bulbo-urethral glands.
• The ejaculatory duct serves as a short passageway (2 cm) starting at the junction of ampulla and seminal gland duct, penetrating and emptying into the prostatic urethra.
• The prostate is a small, muscular organ about 4 cm in diameter that encircles the urethra below the urinary bladder, consisting of 30-50 compound tubulo-alveolar glands.
• It also has prostatic fluid slightly acidic, forms about 25% of semen volume and is ejected by peristalsis.
• Prostatitis can occur which is prostatic inflammation that commonly afflicts older men.
• Bulbo-urethral glands (Cowper's glands) are compound, tubular mucous glands about 10 mm, located at the penis base.
• They secrete thick alkaline mucus used to neutralize urinary acids/lubricate the tip of the penis and its ducts travel alongside/empty into spongey urethra.
• Semen, typically 2-5 mL per ejaculation, an abnormally low volume may indicate prostate/seminal gland issues.
• Sperm count, taken after 36 hrs abstinence, should range 20-100 million sperm/mL.
• Seminal fluid is the same osmotic concentration as blood plasma but has high fructose to be metabolized by sperm and prostaglandins to stimulate tract contractions.
• It also contains Fibrinogen to forms a temporary clot in the vagina.
• Seminal gland secretions are slightly alkaline.
• Semen contains sperm, seminal fluid, and enzymes (protease, seminalplasmin), and Prostatic enzyme/fibrinolysin.
• The penis is a tubular organ that conducts urine to the exterior/semen into female's vagina, with a fixed root attaching to the body wall inferior to pubic symphysis.
• The body (shaft) is its tubular, movable portion.
• The glans penis (head) is expanded to surround external urethral orifice.
• The dermis contains a smooth muscle layer, a continuation of dartos.
• An underlying areolar tissue allows for skin movement.
• Subcutaneous layer contains superficial arteries/veins and lymph vessels
• The foreskin (prepuce) is a fold of skin around the tip of the penis attached at the neck.
• It contains preputial glands which secrete a waxy material and circumcision is its surgical removal has been show to prevent penial cancer and infections..
• The body contains erectile tissue composed of a dense network of elastic fibers encircling vascular channels, incompletely separated by partitions of elastic connective tissue/smooth muscle fibers
• Corpora cavernosa are two cylindrical erectile tissue masses which diverge, forming the "crus" bound to the ischium/pubis with arterial branches constricted/partitions tense
• Corpus spongiosum, a slender erectile body, extends to/forms glans penis, surrounded by a sheath of elastic fibbers

Mitosis, Meiosis, and Spermatogenesis and what they entail

• Mitosis, as part of somatic cell division, produces two diploid (2n) daughter cells.
• These cells possess identical sets of chromosomes and homologous chromosomes
• Meiosis is limited to gamete production with sperm in males and releases four haploid (n) gametes of 23 individual chromosomes.
• The fusion of male/female gametes creates the zygote (46 chromosomes)
• Meiosis see replicated chromosomes condense with two identical chromatids known as synapsis.
• Four matching chromatids form tetrads, and crossing over occurs, exchanging genetic material and resulting in genetic variation for offspring.
• It includes two division cycles: Meiosis I & II
  • Prophase I: the nuclear envelope disappears
  • Metaphase I: Tetrads line up along the metaphase plate
  • Anaphase I: Separation of the tetrads
  • Telophase I: Each daughter cell receives two copies of either the paternal or maternal chromosome which are randomly and independently distributed.
• Telophase I ends with two daughter cells each with 23 chromosomes with two chromatids which is identified as reductional division.
• Interphase is brief and DNA is not Replicated.
• The events proceeding interphase and in Meiosis 2 are equal and unchanging regarding numbers of chromosomes.
• Spermatogenesis is the process of sperm production begins which begins at puberty then continues past age 70 across roughly 64 days.

Spermatogenesis: three steps

1. Mitosis: Spermatogonia are stem cells that divide by mitosis to create two daughter cells, one remain a spermatogonium. the other differentiates into a primary spermatocyte
2. Meiosis: Primary spermatocytes begin the process of meiosis and form secondary spermatocytes at which point secondary spermatocytes differentiate into spermatids. Spermatids are immature gametes.
3. Spermiogenesis: Spermatids mature into sperm.

• At the terminal end; sperm lose contact with the seminiferous tubule walls and are thusly free to enter the lumen in order to mature.
• Seminiferous tubules contain spermatogonia, spermatocytes (meiosis stages), spermatids, sperm, and large nurse cells.
• Sertoli nurse cells play a critical support role in Spermatogenesis and possess the following main functions: blood maintenance of blood testis barrier, mitosis and meiosis support spermiogenesis, inhibin secretions and, secretion of ABP (androgen-binding protein)
• The blood testis protects and separates outer spermatogonia, and inner compartment through tight function which divides the tubule.
• The inner luminal is the location in which meiosis and spermiogenesis occur.
• The production of ABP is stimulated by FSH. This binds to the andrgens in turn raising the concetrations which stimulates speimiogenesis.
• leaving the testes, sperm becomes mature (but immobile) and requires maturity and functional transport.
• This requires two steps known as CAPACITaiton:
  • 1. becoming motile (mixing with seminal glands)
  • 2. capable of functional fertilization by female repr. tract.

Anatomy of Sperm

• Head: contains nucleus with chromosomes
  • Acrosome: compartmental membrane which facilitates fertiization
• Middle: Connected by neck with mitotochria and microtubules
• Tail: flagellum for corkscrew like movement.

Testes

• Testes are the immobile and not yet fertile in sperm.
• After tests mature sperm and other parts are responsible for other nourishment. Sperm from the tests are moved by with cilia.
  • Functional nourishment comes from more support and fluids.
  • Starts in the tail area.

Hormones

• Anterior Lobe of pituitary glands contains and FSH/LH:
• GnRH controls by: rate of secretion, FSh/Lh levels, levels in male
• Testosterone in testicles - in order to secrete the FHS/Gnrh the inhibin tells them when sperm count is full and that there's no more, reducing FSH/GnrH production. Binds for use later. This produces the semen which is regulated FSH (inhibin is peptide hormone)
• Hormones influence sperm production.
  • Leydig cells produce sex hormones.
  • Nurse cells surround the sperm and promote spermatogenesis.
  • It then comes full circle from test and goes back to pituitary/hypothalalmus.

Male Testosterone

• Influences major and normal "male" features.
• When testosterone doesn't need to be produced it turns to DHT on target tissues. Bloodstreams may have DHT in it, 10% of it. Some tissues may use DHT instead
• Can be used to create small amount fo estradiolin plasma (2nng/dl)
  • Happens from circulation and the aromatase eznyme.
    • older men = increase of hormone which isn't know.
  • Nurse cells secrete androgen binding protein (ABP) for use later ABP is supported by FSH.

Female Reproductive Structures: Organs and Functions

• Produces Sex hormones: Utrine and vagina for support! Ovaries.
• The ovaries, uterine tubes, and uterus all connect via BROAD LIGAMENTS! It goes along and opens to other areas. There’s a pocket called Recto-uteral pouch: colon connects to end of uteruus.
• The other pouch is a vesico from another uterus

Ovarian Support Structures

• Contains mesovarium, ovarian ligaments, and Suspensory Ligaments

Anatomy of the Ovary

• Epithelium: this is "germinal epithelium"
• Stroma (Tissues) = Interior tissues of the ovary
  • Cortex = Superficial (most things produced here!)
  • Medulla = Much depper

Uterine/Fallopian Tubes

• Also called Filopian or "Oviduct". its hollow. Is about 13cm long and transports the oocyte to the "Ampulla"
  • Infundibulum: funnel near ovary surface (FIMBRAE projects)
  • Ampulla: Middddle segment with many layers of muscle. Ends near the uterus.
  • Isthmus: Shot between ampulla and wall
  • There are cillia cells with some mucin creating cell

Uterus and what it Provides

• Mechanical Supports. support is from 1-8weeks and fetus 9-delievery
• It's perr shapped roughly 7.5cm x and Weeds about 50-100g. Bends slightly.
• Ligaments: supports with suspenory ligament: Utserosacral ligament protects and prevents lower anterior, Round ligaments prevents and restricts posterior movement. Cardinal ligaments prevent and resist interior movement.
• Uterine parts include the Isthmus, body, and fundus (Rounded portion).
• Distal and end projects vaginal cavity
  • Is a passage way: internal OS leading to cervix --> External OS is distal end which then leads to vagina.

UTERUS Anatomy: Layers and Details to Know

• Layer: Perimetrium: serous.
• Layer: Thick Myometrium. This constitutes 90% of uterus and allows smooth function and mobility.
• Endometrious: Glandular and vascular tissuss with many and endless "glandular surface"
• Estrogens have 10% mass and creates vascular parts and changes to monthly cycles.
• Uterine Artery.
• Arcuate Arteries for Encircle Endometrium
• Radial Arteries Supplies Straight (to basal) and Spirals (to func) arteries. Vagina parts: Muscular lube roughly 9 Cm, Extends between and cervix. Super destensible!
• Functions; 1) Elimination, 2) Sprem, and 3) Inferior Birth.
• Cervis projects to end
• Vaginal Fornix is surrounding
• 2 bulbous spongious muscles, and masss erctile and erectile.

FEMALES

• Also callecd pudendum = Vulva are
• Urethral glads: discharge.
• Clitoris; Is erecticle mass, with minor Labias.
  • Anal canal.
• Vestibules, and smooth, hairless.. Uretha Opens in side and vaginal end.
• Vestibules: lesser vertibule and geater glads. Are exposed. Mucas is to labia for lubrication and to have hair.
• Vaginal Epithleium (nonkeritinized) rugae and forms fold.
• Vaginal Lamina Propia is and Elastics which contains small lymph and nervous.
• Vaginal Mucosa smooth fibers

UTERINE WALL:

• Perimetrium membrane
• Smooth Myometrium, accounts for roughly 90% wall
• Endoometrium, accounts for 10%.
• Function Layer : Uterine and most with functional. thickness "Dramatic change of thickness"
• Basal Later: attached to metro. and has glads.

Breast Anatomy

• Mammary glands or "Specialized Organs" in Intumetgarty system
• Produce milk.
• Hormones control function.
• Lies in adispose.
• Nipple, areaola

Mammry Glands and Milk Production

• Lobes: Several secretouy Lobes. Conectivies,
• Each ducts, the "Lactiferous duct": opens at nipple and has chamber.
• Support is done with. Connective tissue which has, and underlying pectorialis muscles. Active. Tuvolo-alveolar, ending alvioli and pregnancy for for the appartatus!

Gamete Meiosis Process

• Oogenisis (Ova/Over Production):
• Meosis one produces a secondary ooctye and body. Has 24 chromosomes!

Oogenesis; how the bodies change into cells

• Beginds beofre birth
• Before birth contains stem to prodycel.
• Cell do mitosis only till birth... then "primary."
• 7 Million during devleopmpent and 2 till birth.
  • 400 k are used.
• Meosis can't continue! it stops, goes thru seconday oocyte and then fertilzaiton
• As that happens it has 23 individual individual chromosomes! A-s they divide cytoplasms primary is very unven as they prodcue one

Terms

Oogonia are Female cells. Theca allbuginea: Egg nest or outside . Primovial. Follicle that is active has the outer cells aka corona pulucida. Teritary or vesiucal

• Outer cell is theca Inner cells is granulosa.

O VARIAN Cycle and MENSIS

• MONTHLy process with maturations ovualtions and generaions to the ertiery phase. Two things they do:
• Folcullar phase -- outer.
• Luteal. After one leaves behind something Follicular Phase-- Outter is where tertiery phase to the OVARAIAN and it has follicular sells where outer layers, the antrum, granulosa sell produces thecal endocrine. Then lH levels promt the process of messosi. Then it becomes corona radiata outer and granulosa . After it is secondary to ooctye.

Ovulation

• Has corona and is floating with 36 hrs After its done it does another artresia!

LUTEAL Phase post ovulation

• "Corps Luetum"
• They form rom granular cell. It's YELLOW and cholesterol!!! Converts to estroge and progesterines which has Prepares and degreadation. This end.
• Corpos Abucans outer where fibro invasion of start tissue this is at end.

Uterine Cycle - MENSTRUAL. 2 Phases plus 2 in total.

• Repeats and changes the endometerium.
• The first period "menarche" with start at puberty 11 or 12 ends with the "Men Pause" at 50 ish. Three ohses are in this phase. Menstrual: degreads the layer in patches and "Menses" results. Spriail will constrict resulting is this. it then releases it! It loses about 35 to 50 mill blood. "Dysreia" is then the painful moment. This occurs during follicular and pre-polipherative oogenaisis.

Estrogen causes Glands to grow and all activity. So when its. "SECRETORY Phase" all actiitviis takes place.

• then in menstrural "sheds" temp rises a degree but a day after you have very high "low point" then rises high again.

The Uterine Cycle and How It Is is Regulated.

• Pituitary and gonalds control the outer
• Hypothamus sends GnRH: during outter, and progester increases.
• Fsh is low and. outer level then increase
• You lose the hormenes

Male Sexually Repro.

• Reflexes.
  • Symp and parasym. which turns them into ans Aoursal Bulbio secrete! Reflex is stimulated which ejects a stream.
• Under SENSory stimulation
• Periatalitc wave to the. and creates seminal vesicles.
• contracts for the Sphincter. Eeeverything leads to ejaculation!
• Contractions for. "Orgasam” after the resoultio is is complete, Then you have. "DEtumisence:

Erectile Dysfunction - Improtetnicies

AMENORREHA

• Lack of a period! Can be temporary with interuptions.
• STD: and Sexaully Trasnmmited infenctions.
• Can be chlamyydia/ bacterial infection

Development

• 5 wekk
• gonads external and inter. And so no one looks different
• But the the genetic code takes into account for development.
• Testotersone for males is important.

Testis

• They are kidneys ! Next to.
  • "Gubernaculum Testis" bundles connect and it locks
• 7 month and fetus rapidly grows. Which moves to scrotum but some "pockets".
• Menopause

Lades

• The time of over and then stops this happens 45 -55.
• As we go we become pre. mature 40
• estrogen gets higher.
• with decrements which then leads to size in all areas. With thinning with bone depositions is high.
• Hormones are important. For reprodituve purposes. But sperm count most important.
• then PH is very key.

Female

• Ovaries "OOTY" and trans[port happen normally, and for fertilization. For sperms. Everything is all needs to function for a full term which means multiple and a variety needs to be properly!