BIO 169 Chapter 28: The Reproductive System

(Male) Testes

-male gonads secrete androgens and produce sperm (male gamete)

(Male) Descent of Testes

-initially formed inside of body cavity

-during development, testes move inferiorly thru body wall

(Male) Histology of the Testes

-composed of seminiferous tubules connecting to rete testis

-interstitial endocrine cells (produce testosterone)

-immobile spermatozoa moved by cilia from rete testis to epididymis

(Male) Scrotum

-pouch containing testes

-composed of skin, dartos muscle, and fascia

-allows for spermatozoa development at 1.1C lower than body temperature

(Male) Spermatic Cords

-extend between abdominopelvic cavity and testes

-connective tissue and muscle enclose ductus deferens, blood vessels, nerves, and lymphatic vessels

(Male) Spermatogenesis

-formation of spermatozoa

-begins in outer portion of tubules and proceeds toward lumen

(Male) Spermatogenesis, Spermatogonia

-divide forming 1° spermatocyte

(Male) Spermatogenesis, Primary (1°) Spermatocyte

-divide forming 2° spermatocyte

(Male) Spermatogenesis, Secondary (2°) Spermatocyte

-divide forming spermatids

(Male) Spermatogenesis, Spermatid

-immature gametes that mature into spermatozoa (spermiogenesis)

(Male) Spermatogenesis, Spermatozoa

-contains head (with nucleus), acrosome (with enzymes), middle piece       (with mitochondria), and tail (flagellum for movement)

-released into lumen (spermiation) but remain immobile

(Male) Spermatogenesis, Nurse Cells

-promote spermatogenesis

(Male) Epididymis

-coiled tube on back of testes

-monitor and adjust fluid composition

-comprised of head (receives spermatozoa from efferent ductules), body, and tail (spermatozoa storage and protection)

(Male) Ductus deferens (Vas deferens)

-part of spermatic cord from epididymis tail to ampulla

-moves and stores spermatozoa

(Male) Male Urethra

-passageway from bladder to exterior surface

-serves reproductive/urinary system

-receives fluids from ductus deferens, seminal glands, and bladder

(Male) Accessory Glands

-produce fluid component of semen

(Male) Accessory Glands, Seminal Glands

-active tubular gland that secretes majority of semen volume into ejaculatory duct

(Male) Accessory Glands, Prostate Gland

-muscular organ that encircles urethra

-secretes prostatic fluid

(Male) Accessory Glands, Bulbourethral Glands

-small round glands that secrete alkaline fluid

(Male) Semen

-contains spermatozoa (~100 million), seminal fluid (alkaline, fructose, prostaglandins), and enzymes (antibiotics)

(Male) Semen, Capacitation

-spermatozoa become motile when mixed with seminal fluid and capable of fertilization when exposed to female reproductive tract

(Male) Penis

-tubular organ thru which urethra passes

-conduit for urine and semen

-comprised of root (fixed portion), body, and glans penis (distal end)           

(Male) Penis, Erectile Tissue

-multiple vascular channels incompletely separated by connective tissue and smooth muscle

(Male) Penis, Corpora Cavernosa

-two cylindrical masses of erectile tissue surrounded by collagenous sheath

(Male) Penis, Corpus Spongiosum

-slender erectile body surrounded by elastin sheath

(Male) Penis, Non-Arousal

-smooth muscle contracts causing decreased blood flow

(Male) Penis, Arousals

-smooth muscle relaxes causing increased blood flow (erection)

(Male) Hormones, FSH and Testosterone

-targets Nurse cells and promotes spermatogenesis and spermiogenesis

(Male) Hormones, LH

-targets interstitial cells and promotes secondary sex characteristics

(Female) Ovaries

-female gonads secrete estrogen and progesterone and produce oocytes (female gamete)

(Female) Ovarian Support, Ovarian Ligament

-extend from uterus to ovary

(Female) Ovarian Support, Suspensory Ligament

-extend from pelvis to ovary

(Female) Ovarian Support, Mesovarium

-thickened stabilizing mesentery

(Female) Uterine Tubes

-hollow muscular tubes that transport oocyte to uterus

-oocyte movement involves ciliary motion and peristaltic contractions

(Female) Uterine Tubes, Infundibulum

-expanded funnel near ovary with fimbriae (projections)

(Female) Uterine Tubes, Ampulla

-middle segment

(Female) Uterine Tubes, Isthmus

-short segment between ampulla and uterine wall

(Female) Uterus

-provides mechanical and nutritional support for the developing baby

(Female) Uterus, Uterine Body

-fundus is rounded superior portion

-isthmus is constricted inferior end

(Female) Uterus, Cervix

-inferior portion extends to vagina

(Female) Uterus, Perimetrium

-incomplete serous membrane covers fundus, isthmus, and posterior body

(Female) Uterus, Myometrium

-thick, middle muscular layer

-smooth muscle arranged in longitudinal, circular, oblique layers

-provides strong forces during childbirth

(Female) Uterus, Endometrium

-thin, inner, glandular layer that supports physiological demands

-estrogens cause uterine glands, blood vessels, and epithelia to change monthly

(Female) Uterus, Endometrium Functional Layer

-contains uterine glands

-undergoes most changes in thickness during uterine cycle

(Female) Uterus, Endometrium Basal Layer

-attaches endometrium/myometrium

-remains relatively constant during uterine cycle

(Female) Vagina

-elastic muscular tube extending from cervix to vestibule

-comprised of epithelia, lamina propria, mucosa (with smooth muscle)

-serves as conduit for menstrual fluids, spermatozoa and during childbirth

(Female) External Genitalia, Vulva

-area containing external genitalia

(Female) External Genitalia, Vestibule

-central space bounded by labia minora (small folds)

(Female) External Genitalia, Clitoris

-small projection of erectile tissue in vestibule

(Female) External Genitalia, Mons Pubis and Labia Majora

-adipose tissue that serve to protect and cover inner structures

(Female) Breasts, Mammary Glands

-specialized organs that produce milk to nourish infant

(Female) Breasts, Nipple

-contains ducts to mammary glands

(Female) Breasts, Areola

-pigmented area around each nipple

(Female) Oogenesis

-ovum production that begins at birth, accelerates at puberty and ends at menopause

(Female) Oogenesis, Oogonia

-in fetal ovaries

-divide forming a primary oocyte (before birth)

(Female) Oogenesis, Primary (1°) Oocyte

-some divide forming secondary oocyte (during ovarian cycle)

(Female) Oogenesis, Secondary (2°) Oocyte

-divide forming ovum (occurs at fertilization)

(Female) Ovarian Follicle

-specialized structures in ovarian cortex where oocyte growth occurs

(Female) Ovarian Follicle, Primordial Ovarian Follicle

-primary oocyte and surrounding follicle cells

(Female) Ovarian Follicle, Primary (1°) Ovarian Follicle

-formed by activated primordial ovarian follicle

(Female) Ovarian Follicle, Secondary (2°) Ovarian Follicle

-forms from primary ovarian follicle

(Female) Ovarian Follicle, Tertiary (3°) Ovarian Follicle

-follicular fluid accumulates causing doubling of size

(Female) Ovarian Cycle

-monthly process of maturation, ovulation, and degeneration of tertiary ovarian follicle

(Female) Ovarian Cycle, Follicular Phase

-tertiary ovarian follicle creates bulge in ovary

-granulosa cells associate with secondary oocyte (corona radiata)

(Female) Ovarian Cycle, Ovulation

-tertiary follicle releases secondary oocyte into pelvic cavity

-oocyte moves into uterine tube via fimbriae or by fluid currents

(Female) Ovarian Cycle, Luteal Phase

-postovulatory phase

(Female) Ovarian Cycle, Corpus Luteum

-forms from remaining granulosa cells

-secrete estrogens

-begin degenerating ~12 days after ovulation

(Female) Ovarian Cycle, Corpus Albicans

-produced from nonfunctional corpus luteum as fibroblasts invade and form scar tissue

-marks end of ovarian cycle

(Female) Uterine Cycle

-repeating series of changes in endometrium

-lasts from 21-35 days

(Female) Uterine Cycle, Menstrual Phase

-degeneration of endometrial functional layer

-constricted blood vessels cause reduced blood flow, O₂, and nutrients

-blood vessels rupture releasing blood into connective tissue of functional layer

(Female) Uterine Cycle, Proliferative Phase

-epithelial cells of uterine glands multiply, spread across endometrial           surface

-further growth/vascularization restores functional layer

-occurs at same time as enlargement of tertiary ovarian follicles (produces estrogens which stimulate/sustain)

(Female) Uterine Cycle, Secretory Phase

-uterine glands enlarge

-begins at ovulation and persists as long as corpus luteum remains intact

-ends as corpus luteum stops producing hormones

(Female) Female Reproductive Cycle

-controlled by hormones of the pituitary glands and gonads

-forms a complex pattern that coordinates ovarian and uterine cycles

(Female) Female Reproductive Cycle, Release of GnRH

-causes production/secretion of FSH and production of LH

(Female) Female Reproductive Cycle, Follicular Phase of Ovarian Cycle

-FSH stimulates development of tertiary ovarian follicle

-developing ovarian follicles secrete estrogens, FSH levels decline, and LH levels increase

(Female) Female Reproductive Cycle, Luteal Phase of Ovarian Cycle

-LH levels continue to increase leading to ovulation

-corpus luteum secretes progesterone leading to endometrial development

-estrogen levels fall, GnRH levels fall

-if pregnancy does not occur, corpus luteum degenerates, progesterone falls, GnRH increases for new cycle