Reproductive System Flashcards
Gonads
Primary sex organs
Testes and ovaries
Gametes
Sex cells- eggs and sperm
Parts of the duct system in testes
Epididymis
Ductus (vas) deferens
Urethra
Accessory male organs
Seminal glands (vesicles)
Prostate
Bulbourethal glands
External genitalia
Penis and scrotum
What connects testis to trunk?
Spermatic cord
What does the spermatic cord contain?
Blood vessels
Nerves
Ductus deferens
Tunica albuginea
Capsule that surrounds each testis
Septa
Divide testis into lobules. Extension of capsule
How many seminiferous tubules does each lobule have?
1-4
Seminiferous tubules
- Tightly coiled structures
- Act as sperm makers
- Empties sperm into rete testis
Sperm travels from the rete testis to the
Epididymis
Interstitial cells in the seminiferous tubules make androgens like
Testosterone
Epididymis length
6m, 20 ft
Very convoluted
Where to find epididymis?
Posterior lateral side of the testis
What is the first part of the male duct system?
Epididymis
Function of epididymis
Temporary storage for immature sperm
Sperm matures as it journeys through the
Epididymis
During ejaculation, sperm are propelled to the
Ductus deferens
Passage of the ductus deferens
From epididymis to spermatic cord through inguinal canal and over urinary bladder
Ampulla
End of ductus deferens, empties into ejaculatory duct
Ejaculatory duct
Passes through prostate to merge with urethra
How does sperm move into urethra
By peristalsis
Urethra passage
From bladder to tip of penis
Sperm enters urethra via the
Ejaculatory duct
Prostatic urethra
Surrounded by prostate gland
Membranous urethra
Prostatic urethra to penis
Spongy urethra
Penile
Runs through length of penis
What happens to the internal urethral sphincter when men ejaculate ?
It closes to stop urine from going into urethra and it prevents sperm from entering the urinary bladder
Seminal vesicles location
Base of bladder
Seminal vesicles secretion
60% semen
Fructose
Vitamin c
Prostaglandins
Other substances that nourish and activate sperm
Duct of each seminal vesicle joins the ____ _______ on each side to make
Ductus deferens
Ejaculatory duct
Prostatic secretions
Help activate sperm
Fluid enters urethra through several small ducts
Milky appearance
Bulbourethal glands appearance and location
Pea sized, inferior to prostate
Bulbourethal glands
Make thick, clear mucus that cleans penile urethra of acidic urine before ejaculation
Mucus also helps lubricate during sexual intercourse
Semen
Milky white mixture of sperm and accessory gland secretions
Liquid portion of accessory gland secretions serve to
Dilute sperm
Streamlined tadpoles
Sperm
Function of fructose in ejaculatory fluid
Gives energy to sperm cells
Why are sperm alkaline
To neutralize acidic environment of vagina
Semen ____ bacteria
Inhibits
Scrotum
Divided sac of skin that houses the testes
Why are testes outside?
Why do we need scrotum?
Viable sperm can’t be made at body temperature
Keeps testes 3 C lower than normal body temperature
Male organ of copulation that delivers sperm into the female reproductive tract
Penis
Regions of penis
Shaft
Glans penis (enlarged tip)
Prepuce (foreskin)
Folded cuff of skin around proximal end of penis
Prepuce (foreskin)
When do erections happen?
When erectile tissue fills with blood during sexual excitement
Chief roles in male reproductive process
Make sperm and testosterone
When does sperm production begin?
Puberty, and continues throughout life
Millions made very day
Spermatogonia
primitive stem cells, begin sperm making process by dividing rapidly
During puberty, FSH production
Increases
During spermatogenesis, each division of. Spermatogoniun cell produces
Type A daughter cell
Type B daughter cell
Type A daughter cell
Stem cell that continues stem cell population
Type B daughter cell
becomes primary spermatocyte, designed to form 4 sperm through meiosis
Meiosis
Special type of nuclear division different from mitosis
Meiosis occurs in the
Gonads
Includes two successive divisions of the nucleus
Meiosis I and II
Makes 4 daughter cells
How many chromosomes in gametes?
23
Haploid number
23 (n) half genetic material as other body cells
Zygote
Union of sperm with an egg (2n)
Spermatids are nonmotile and not functional as ____
Sperm
Spermiogenesis
Streamlining process needed to get rid of excess cytoplasm and turn spermatid into sperm
Regions of sperm
Head, mid-piece, tail
Acrosome
Sits anterior to head (nucleus)
Length of spermatogenesis including spermiogenesis
64-72 days
Head of sperm
Has genetic material
Can penetrate follicle cell capsule
Mid-piece of sperm
Has lots of mitochondria, makes energy to move
Tail
Movement, flagellum
How does testosterone production during puberty occur?
FSH prods seminiferous tubules to produce sperm
LH activates interstitial cells to make testosterone
Most important hormonal product of the testes
Testosterone
What stimulates reproductive organ development in males?
Testosterone
What underlies sex drive in males?
Testosterone
Testosterone causes secondary sex characteristics like
- Deepening voice
-increased hair growth
-enlargement of skeletal muscle
-increased bone growth and density
Anatomy of the female reproductive system
Ovaries
Duct system
External genitalia
Duct system of females
-Uterine (fallopian) tubes
-uterus
-vagina
Ovaries function
Make ova, estrogen and progesterone
Each ovary houses ovarian follicles made of
Oocytes
Follicle cells
Oocytes
Immature eggs
Follicle cells
Layers of different cells that surround oocyte
Primary ovarian follicle
Contains immature oocyte
Vesicular (graafian) follicle
Growing follicle with maturing oocyte
Ovulation
Follicle ruptures when the egg is mature and ready to be ejected by ovary; happens about every 28 days
Ruptured follicle turns into
Corpus luteum which makes progesterone during early pregnancy
Suspensory ligaments
secure ovaries to lateral walls of pelvis
Ovarian ligaments
Anchor ovaries to the uterus medially
Broad ligaments
Fold of peritoneum
Enclose and hold ovaries in place
Form initial part of female duct system
Fallopian tubes
Function of fallopian tubes
1.Receive ovulated oocyte from ovaries
2.Provides site of fertilization
3.Empties into uterus
There is little to no contact between the ___ and the ____ _____
Ovaries and the uterine tubes
The fallopian tubes empty into the
Uterus
What is supported and enclosed by the broad ligament
Uterine tubes
Infundibilum
Distal, funnel-shaped end of fallopian tubes
Fimbriae
- Fingerlike projections of the infundibilum
Fimbriae function
Receive oocyte from ovary
(Capture eggs from ovary)
Function of cilia in fimbriae
Transport the oocyte
Uterus location
Between bladder and rectum
Size and shape of uterus
Size and shape of pear in woman that has never been pregnant
Function of uterus
Receives, retains and nourishes a fertilized egg
Uterine support
1.Broad ligament suspends uterus in pelvis
2.Round ligament anchors uterus anteriorly
3. Uterosacral ligament anchors uterus posteriorly
Regions of cervix
Body-main portion
Fundus- upper rounded region where tubes enter
Cervix- narrow outlet that protrudes into vagina
Layers of the uterus
Endoneurium
Myometrium
Perineurium
Endometrium
Inner layer (mucosa)
Site of implantation for fertilized egg
Sloughs off if no pregnancy happens (menstruation)
Myometrium
Middle layer of smooth muscle that contracts during labor
Perimetrium
Visceral peritoneum
Outermost, serous layer of uterus
Vagina
Passageway from cervix to outside between bladder and rectum
Serves as canal that lets baby or menstrual flow leave body
Vagina
Female organ of copulation
Vagina
Hymen
Partially closes vagina until it is ruptured
Parts of female external genitalia
Mons pubis
Labia
Clitoris
Urethral orifice
Vaginal orifice
Greater vestibular glands
Mons pubis
Fatty area over pubic symphysis
Covered with hair after puberty
Labia majora
Hair covered skin folds
Enclose labia minora
Encloses the vestibule
Labia minora
Delicate, hair-free folds of skin
Vestibule
Enclosed by labia majora
Contains external openings of urethra and vagina
Greater vestibular glands
One on each of vaginal
Lubricate vagina during intercourse
Clitoris
Has erectile tissue
Doesn’t have duct
Similarities between clitoris and penis
1.Hooded by prepuce
2.Made of sensitive erectile tissue
3.Swollen with blood during excitement
Perineum
Diamond shaped
Between labial folds, anus and ischial tuberosities
Total amount of eggs is determined when?
By time woman is born
Ability to release eggs begins at
Puberty with menstrual cycle
Reproductive ability ends at
Menopause (in fifties)
Oogenesis
Process of making ova
Oogonia
Female stem cells found in developing fetus
How do Oogonia reproduce
Oogonia replicate by mitosis and make primary oocytes
The primary oocytes are surrounded by cells that make primary follicles in the ovary
Primary Oocytes are inactive until
Puberty
FSH causes some primary follicles to
Mature each month
Ovarian cycle
Cyclic monthly changes
How does meiosis start in a maturing follicle?
- First meiotic division makes a larger secondary oocyte and a smaller first polar body
- Vesicular follicle has secondary oocyte.
Maturation from a primary follicle takes __ days
14
Ovulation of a secondary oocyte occurs with the release of
Lutenizing hormone LH
Secondary oocyte is released and surrounded by
Corona radiata
Meiosis is completed after ovulation only if
Sperm penetrates the oocyte
What occurs if sperm penetrates the oocyte?
Ovum is produced
Two additional polar bodies are produced
Once ovum is formed,
the two pairs of 23 chromosomes combine to make fertilized egg
What happens if secondary oocyte is not penetrated by sperm?
It dies
Meiosis in males produces
4 functional sperm
Meiosis in females produces
One functional ovum and three polar bodies
Comparison of sex cells
Sperm are tiny, motile, have nutrients in fluid
Egg are large, nonmotile and has nutrient reserves to nourish embryo until implantation
Estrogens are produced by
Follicle cells
What does estrogen do?
Causes secondary sex characteristics:
- enlarge accessory organs
-breast development
-body hair
-increase fat in hips and breasts
-widening and lightening of pelvis
-onset of menstrual cycle
Progesterone is made by
Corpus luteum
Progesterone production continues until
LH diminishes in blood
Which hormone does not contribute to secondary sex characteristics?
Progesterone
Major effects of progesterone
Maintain pregnancy
Prepare breasts for milk production
Cyclic changes of endometrium are how long?
28 days
What regulates menstrual cycle
The cyclic production of estrogen and progesterone by ovaries
Which hormones from the anterior pituitary regulate the production of estrogens and progesterone by the ovaries?
FSH and LH
When does ovulation typically occur?
About midway through cycle, day 14
Stages of menstrual cycle
- Menstrual phase
- Proliferative stage
- Secretory stage
Menstrual phase (days 1-5)
1.Functional endometrium is shedded
2.Bleeding happens for 3-5 days
3. Ovarian hormones at their lowest
4. By day 5, ovarian follicles make more estrogen
Proliferative phase
1.Days 6-14
2.Regeneration of endometrium
3. Estrogen rises
4. Ovulation happens in the ovary at the end of this stage
Secretory stage
Days 15-28
Progesterone rises, endometrium gets more blood supply to prep for implantation, endometrium gets bigger
If fertilization occurs
Embryo makes hormone that causes corpus luteum to keep making hormones
If fertilization doesn’t happen
Corpus luteum degenerates as LH blood levels decline,
Repeated every 28 days
Mammary glands are present in
Both sexes, but only function in females
Modified sweat glands
Mammary glands
Mammary glands function to
Make milk to nourish newborn
Areola
Central pigmented area
Nipple
Protruding center of areola
Lobes of mammary glands
Internal structures, radiate around nipple
Lobules
Located within each lobe and contain clusters of alveolar glands
Alveolar glands
Make milk when woman is lactating
Lactiferous ducts
Connect alveolar glands to nipples
Lactiferous sinus
Dilated portion where milk accumulates