Reproductive system Flashcards
Determination of Sex (2)
Most vertebrates have two genders;
- Genetically-determined (mammals Xy = males; XX = females)
- Environmentally determined (such as in reptiles & amphibians)
Define;-
- gonads (what called in males & females)
- Gametes
- function of ducts
- Gonads: Primary sex organs (also produce lots of sex hormones)
- ovaries in females
- testes in male
- Gametes: sex cells produced by gonads
- oocytes =female
- sperm = male
- Functions of ducts: to transport gametes to site of fertilisation
Reproductive System Homologue
- Ovaries
- clitoris
- Labia majora
- Vestibular glands
- Ovaries & Testes: produce games and sex hormones
- Clitoris & glans of penis: contain autonomic nervous system that stimulate feelings of arousal and sexual climax
- Labia majora & scrotum: protect and cover some reporductive structures
- vestibular glands & bulbourethral glands: screte mucin for lubrication
Functions of female reproductive organs (5)
- Produce ovum
- Facilitate transport of sperm to site of fertilisation
- provide sanctuary and nourishment for developing embryo
- Provide passage for birth
- Provide nourishment for young
Female reproductive organs:
- primary
- accessory organs (5)
- Primary organs: Ovaries
- Accessory organs;-
- Uterine tubes
- Uterus
- Vagina
- Clitoris
- Mammary glands
Ovaries
-How anchored to pelvic cavity
-Are paired, oval organs, slightly larger than an almond
-Anchored within pelvic cavity by; mesocarium broad ligament ovarian ligament suspensory ligament
Structure of Ovary
- Surrounded by connective tissue capsule called tunica albuginea
- Divided to outer cortex & inner medulla
- cortex contains ovarian follicles
- medullar contains CT, blood vessels, lymph vessels & nerves
Ovarian follicles
- Thousands of ovarian follicles in cortex of ovary
- Consist of an oocyte surrounded by follicle cells
- Several types of ovarian follicles, each representing different stage of development
Stages of Ovarian follicle maturation
- Primordial follicle
- Primary follicle
- Secondary follicle
- Mature follicle
*When mature follicle ruptures and expels its oocyte, the remnants in ovary turn yellowish structure = Corpus tuteam -secretes sex hormones
Uterine Tube (4 continuous regions)
- Infundibulum: lateral opening of tube encircled by fingerlike projections
- Ampulla: expanded region medial to infundibulum where fertilisation typically occurs
- Isthmus: just medial to ampulla - approx. 1/3 of entire length
- Uterine part: continuous w/ uterus
3 layers of the walls of the uterine tubes
- Mucosa: Ciliated columnar epithelial cells
- Muscularis: inner circular layer and an outer longitudinal layer of smooth muscle
- Serosa: external serous membrane covering uterine tube
Ectopic implantation
-Where egg embeds in an abnormal site
Uterus
- position
- anteverted and retroverted
- pear shaped, thick-walled muscular organ w/in pelvic cavity
- Has lumen that is continuous w/ uterine tubes
- angled anterosuperiorly across superior surface of urinary bladder (ANTEVERTED)
- is positioned projecting towards rectum = retroverted
Functions of uterus
- Site of implantation
- Supports and protects developing embryo/fetus
- Ejects fetus during labour
4 regions of uterus
-Muscular wall, external serous membrane & internal vascular epithelium
- Fundus (upper part)
- Body
- Isthmus
- Cervix
Muscular wall = myometrium
- external serous membrane
- internal vascular epithelium
Blood supply to uterus
-Uterine arteries: branches from internal iliac arteries that supply the uterus
Vagina - features
- vulva - 2 types
- Vestible - what it houses
-A fibromuscular tube approx. 10cm in length
-connects uterus to outside of body
-Vaginal orifice: Opening of vagina
Vulva: External genitalia
-labia majora: paired, thickened folds of skin, covered w/ hair, possessing sebaceous and sweat glands
-labia minora: paired folds medial to labia majora, devoid of hair, highly vascularised w/ numerous melanocytes
Vestible: space between labia minora
-houses urethral opening and vaginal opening
Mammary Glands -what they are
-divisions
aka breast
- Composed of tubulaoalveolar exocrine gland
- secretory product (aka milk) contains proteins, fats and sugar
- subdivided into lobes, further divided into lobules
- lobules contain secretory units called aveoli (what produces milk)
What determines maleness?
- SIngle gene (SRY) on Y chromosome changes pattern of dvelopment in fetal gonad to that of a testis
- absence leads to XY female phenotype
Androgen insensitivity syndrom
- tissues of reproductive organ system not responding, female characteristics develop, although male genetically
- usually not diagnosed until puberty
Organs of male reproductive system
- Primary
- Accessory
Primary: testes
Accessory organs: ducts and tubles, penis
Scrotum
-muscle
- skin covered sac - provides testes w/ cooler environ (optimum temp is 3 degrees lower than body temp)
- dartos muscle layer of smooth muscle that is part of wall of scrotum - brings testes closer in cold, lowers them when hot
Spermatic cord
- where originates
- Components (4)
-Originates at inguinal canal
-enclosed w/in pocket of periotenium
Consists of;-
-Testicular artery (branch off the abdominal aorta
-Pampiniform plexus (network of veins surrounding testicular atery)
-Cremaster muscle & fascia: formed from muscle fiber extensions of internal oblique muscle
-Autonomic nerves: travel w/ plexus and connect to testes (involved in regulation)
Functions of Testes (2)
- Produce sperm
2. Hormone production
Testes
- Ovoid in structure, approx. 4 cm long
- Tunica albuginea projects internally into the testes to form septa
- septa subdivide to form about 250 lobules
- each lobule contains four convoluted seminiferous tubules (in each)
Seminiferous Tubules - 2 types of cells
- Conatin 2 types of cells;
1. Sustentacular cells: nondividing support cells that assist w/ sperm development; connected to each other by tight junctions and form blood-testis barrier (so blood doesnt come in direct contact w/ sperm)
2. Population of dividing germ cells that continuously produce sperm - begins at puberty
Spermatogenesis & Spermiogenesis
- Most of maturation of sperm occurs in epididimus
- get rid of anything they don’t need
- Midpiece contains lots of mitochondria (as well as centriole)
- Tail forms from microtubules
- acrosome cap - contains digestive enzymes that are needed for fertilisation
Ducts in Male reproductive system (6)
- Rete testis
- Efferent ductules
- Epididymus
- Ductus deferens
- Ejaculatory duct
- Urethra
Epidiymis
- 3 parts
- function
-Situated on the posterosuperior surface of the testes
3 regions;
1. Head
2. Body
3. Tail
Internally, contains long convoluted duct of epidiymis - stores sperm and serves in the maturation process of sperm
Ductus Deferens
- Sperm leaving epidiymis enter the ductus deferens (vas deferens)
- Tube travels w/in spermatic cord and enters pelvic cavity through inguinal canal
Urethra
-Transports semen from both ejaculatory ducts to the outside of body
-transports urine from bladder to outside of body
3 portions:
1. Prostatic urethra
2. Membranous urethra
3. Spongy urethra
Accessory Glands -3 glands
-what 3 glands do
-Three glands that secrete fluids to mix w/ sperm to create seminal fluid
-nourish sperm & help neutralize acidity of vagina
3 glands:
1. Seminal vesicles: nourishment
2. Prostate gland: produces nourishment & mucous
3. Bulbourethral glands: secretions before ejaculation to clean out urethra
Seminal vesicles - what it secretes
Prostrate secretion
Bulbourethral glands
Seminal vesicles: secrete viscous, whitish-yellow, alkaline fluid containing fructose (ENERGY) and prostaglandis (TYPE OF HORMONE - stimulates cervix to relax)
- prostrate secretion: slightly acidic & contains mucin, citric acid and antibacterial agents
- Bulbourethral glands: secrete mucin into spongy urethra at base of penis - flushes before ejaculation
Semen - what is it
- Seminal fluid from 3 accessory glands combines w/ sperm to make up semen
- when released during ejaculation = ejaculate
- usu. 3-5ml, contains 200-500 million sperm
Penis
- Penis & scrotum form external genitalia in males
- Internally, attached portion = root of penis
- Body (shaft) is elongated portion
- Tip of penis = glans (slightly bulbous in shape) - surrounds external urethral orifice
-Lots of spaces w/in spongy tissue to allow structure to become rigid
Penis
- Penis & scrotum form external genitalia in males
- Internally, attached portion = root of penis
- Body (shaft) is elongated portion
- Tip of penis = glans (slightly bulbous in shape) - surrounds external urethral orifice
-Lots of spaces w/in spongy tissue to allow structure to become rigid
Erectile bodies w/in penis (3)
- Are parallel, cylindrical erectile bodies;
1. Paired Copora cavernosa - located dorsolaterally & terminate at distal shaft of penis
2. Single copus spongiosum: inferior and midline that surrounds spongy urethra
3. Distal end of corpus spongiosum continues w/in glans
Erection and Ejaculation
- Erectile bodies composed of venous spaces - fill w/ blood from a central artery to produce an erection
- Parasympathetic nervation responsible for penile erection
- Ejaculation: expelling of semen from the penis by rhythmic contraction of the smooth muscle of the urethra (causes ejaculation - also from pelvic muscles)
- Sympathetic innervation promotes ejaculation
