Unit 8: Reproductive Systems Flashcards
What do primary sex organs produce? Name both.
Produce gametes
Ovaries and Testes
What are the purpose of secondary sex organs?
Essential for reproduction
What are the male secondary sex organs? What are their altogether purpose?
Duct, glands, and penis
Deliver sperm cells
What are the female secondary sex organs? What are their altogether purpose?
Uterine/fallopian tubes, uterus, and vagina
Receive sperm and nourish a growing fetus
What are the functions of the male reproductive system?
Produce sperm
Produce sex hormones
Deliver sperm
Where is sperm produced in the testes?
Seminiferous tubules
Seminiferous tubules drain into the tubular network called the ________
rete testis
What are the 2 main cells in testes?
Sertoli (“nurse”) cells
Spermatogenic cells
What is the role of Sertoli cells?
Nourish and protect spermatogenic cells
What is the role of Spermatogenic cells?
Divide to create new sperm cells
What is the purpose of the scrotum?
Thermoregulation
Which 3 tissues in the scrotum control thermoregulation of the testes?
Cremaster muscle
Dartos muscle
Venous plexus
Define scrotum
Pouch that holds testes
Define spermatic cord. Where does run through?
Blood vessels, lymph vessels, and ductus deferens which run through the inguinal canal
How does the cremaster muscle promote thermoregulation?
They are segments of the internal oblique muscle which can contract to pull the testes closer to the body when cold
How does the dartos muscle promote thermoregulation?
Smooth muscles that can wrinkle the skin around the scrotum to decrease surface area to preserve heat
How does the venous plexus promote thermoregulation?
The countercurrent heat exchange keeps the testes at a consistent temperature
Describe how the countercurrent heat exchange works in the venous plexus
Arterial blood cools as it descends into testis and warms back up in vein when returning to body
Artery and vein run next to eachother so constantly exchange heat to regulate
Name the 4 spermatic ducts
Efferent ductules
Epididymis
Ductus deferens
Ejaculatory duct
The spermatic ducts are _________ sex organs
secondary
Describe the efferent ductules in the testis
A passageway from the rete testis to the epididymis
Describe the epididymis
Site of sperm maturation and storage
Describe the ductus deferens
Passageway from the epididymis to the ejaculatory duct
Describe the ejaculatory duct
Leads to prostatic urethra
Describe the pathway of sperm from beginning to ejaculation
Seminiferous tubules - rete testis - efferent ductules - epididymis - ductus deferens - ejaculatory duct
Name the 3 accessory glands which contribute to seminal fluid
Seminal vesicles
Prostate gland
Bulbourethral gland
What are the 3 contributions to seminal fluid from the seminal vesicles? What is the purpose of each?
Fructose (ENERGY for sperm)
Fibrinogen (sticky semen)
Prostaglandins (stimulate female peristalsis)
What are the 2 contributions to seminal fluid from the prostate gland? What is the purpose of each?
Fibrinolysin (liquefy sticky fibrinogen after 30 min so it can MOVE up canal)
Spermine (base which stabilizes seminal pH @ 7.2-7.6)
What is the 1 contribution to seminal fluid from the bulbourethral gland? What is its purpose?
Alkaline pre-ejaculatory fluid (CLEANS out urethra and lubricates)
The penis is a ________ sex organ
secondary
What are 3 parts of the penis? What are the 3 tissues?
Internal root, visible shaft, and glans
1 corpus spongiosum
2 corpora cavernosa
Describe the corpus spongiosum
Tissue on bottom side of the penis which extends to the glans and surrounds the urethra
Describe the corpora cavernosa
2 bilaterial cylindrical tissues on top side of penis which have lacunae that fill with blood to erect the penis
What stimulates the beginning of male puberty? What happens in male puberty?
Increase in pituitary gonadotropins LH and FSH
Sperm production and testosterone release
What are the effects of increased testosterone levels in puberty?
Facial, pubic, and chest hair
Deep voice
Broader shoulders and muscle mass
What does FSH promote in male puberty?
Sperm production
What does LH promote in male puberty?
Testosterone production
What are the 5 functions of the female reproductive system?
Produce and deliver ova
Produce sex hormones
Provide nourishment and room for fetus
Birth
Nourish infant
What do the ovaries produce?
Eggs (ovum) and female hormones
Where do the eggs develop?
Within a fluid-filled follicle in the ovary
What are the 2 ligaments related to the ovaries?
Ovarian ligament (ovary-uterus)
Suspensory ligament (ovary-pelvic wall)
What are the internal genitalia of females?
Duct system (uterine tubes, uterus, and vagina)
What are the external genitalia of females?
Clitoris, labia minora, labia majora, and accessory glands (for lubrication)
The fallopian/uterine tubes are a _______ sex organ
secondary
Describe the fallopian/uterine tubes
Muscular tubes lined with ciliated cells
Fimbriae “catch” the released egg and move to tube
What are the 3 layers of the uterus?
Perimetrium
Myometrium
Endometrium
Describe the perimetrium
Outer serous layer of uterus
Describe the myometrium
Middle smooth muscle layer of uterus
Describe the endometrium
Inner tissue of uterus with 2 layers
Stratum functionalis = superficial layer
Stratum basalis = deep layer
What does the stratum functionalis do?
Sheds with each period if not pregnant
If pregnant, nourishes fetus until placenta organ grows
What does the stratum basalis do?
Regenerates new stratum functionalis each cycle
Describe the vagina and its function
Distensible/Stretchy muscular tube
Discharges menstrual fluid, births baby, receives semen
What are the 3 tissue layers of the vagina?
Outer serosa, middle muscularis, and inner mucosa
What does bacteria do in the vagina? What is the effect on pH?
Ferments glycogen in epithelial cells which makes pH acidic
Define transudation
The process by which erectile tissue around the vagina wall squeezes fluid out to lubricate when aroused
What are the 4 parts of the vulva?
Mons pubis
Labia majora
Labia minora
Vestibule
Define mons pubis
Mound of fat over the pubic symphysis
Describe the labia majora and labia minora. What do they form?
Thicker folds of skin with pubic hair
Thinner, middle folds of skin without hair
Form vestibule containing the urethra and vaginal opening, as well as the prepuce over the clitoris
Define vestibular bulbs
Erectile tissue around vagina which narrows vagina around the penis
Define greater and lesser vestibular glands
Glands which open in vestibule to provide lubrication
Breasts are secondary _______ __________
sex characteristics
Describe breasts
Adipose tissue with areola surrounding nipple
Is a modified sweat gland with mostly ducts and fat unless pregnant (which increases glandular tissue)
What triggers puberty in women?
Increase in GnRH (gonadotropin releasing hormone) which triggers anterior pituitary to release gonadotropins FSH and LH
Define menarche
First menstrual period
Which hormone causes development of sex characteristics?
Estrogen
Sexual reproduction involves ______ from both parents
genetic material
Zygote is formed by
male and female gametes
(sperm + egg)
Cells contain ______ pairs of chromosomes
23
Male sex chromosome pair =
XY
Female sex chromosome pair =
XX
Define SRY gene
Sex-determining Region of Y gene
What does the SRY gene do
In males, it codes for TDF (testis determining factor) protein which causes the development of testes in utero
What happens if the TDF protein is present?
Increased sensitivity to testosterone
Leydig/interstitial cells secrete testosterone
Sertoli cells secrete MIF (mullerian-inhibiting factor)
Mesonephric ducts devolop and paramesonephric ducts degrade
= MALE!
What is MIF?
Mullerian-inhibiting factor
Causes the paramesonephric ducts to degenerate so that female sex organs do not grow
No Y chromosome means no ____ gene which means
No SRY gene = no male hormones = FEMALE!
When do gonads develop in utero? How long are they identical? How are they identical?
6 weeks after fertilization = gonadal ridges
Identical from week 8-10
Have both mesonephric and paramesonephric ducts
The presence of testosterone and MIF =
mesonephric ducts develop
paramesonephric ducts degenerate
The absence of testosterone and MIF =
paramesonephric ducts develop
mesonephric ducts degenerate
By the end of week 12, the 3 structures become distinctly M/F
Penis OR clitoris
Penile skin OR labia minora
Scrotal skin OR labia majora
Why do testes descend from the pelvis
Because sperm need lower temperatures to develop and mature
What connects the testis to the abdominopelvic floor?
Gubernaculum (cord)
What is the difference between mitosis and meisosis?
Purpose?
Product?
Divisions?
Mitosis: growth, repair, replace old cells
1 cell division to produce 2 identical diploid cells (has 46 chromosomes each)
Meiosis: sexual reproduction
2 cell divisions to produce 4 haploid gametes (23 chromosomes, will join with other parent gamete)
What mechanisms take place during meiosis to provide genetic diversity?
Crossing over, recombination, and random assortment
Describe the first cell division in meiosis
Meiosis I
One homologous chromosome separates into 2 haploid cells
Describe the second cell division in meiosis
Meiosis II
The 2 haploid cells duplicate sister chromatids and then separate into 4 haploid cells
What are germ cells in germinal epithelium?
Stem cells that produce gametes
How do Sertoli cells promote sperm cell development?
Blood-Testis barrier is formed between tight junctions between sertoli cells
This keeps immune cells in the blood stream from attacking new sperm cells
Spermatagonia produces 2 types of daughter cells. Describe them
Type A
Cells outside blood-testis barrier which produce more cells until death
Type B
Cells which become spermatocytes that travel across blood-testis barrier to the lumen of seminiferous tubules
Describe meoisis of sperm cells
Primary spermatocyte splits into 2 secondary spermatocytes
Secondary spermatocytes duplicate chromatids and then split into 4 spermatids
Spermiogenesis turns ____ into _____. How?
Spermatid to Spermatozoa
Discards extra cytoplasm and grows tail
What are the parts of a spermatozoa
Head, midpiece, and tail
What is in the head of a spermatozoa
Nucleus with the haploid chromosomes
Acrosome with enzymes that penetrate the egg
What is in the midpiece of a spermatozoa
Mitochondria which produce ATP for the flagellar movement of the tail
Oogenesis happens
once a month
Spermatogenesis happens
Constantly
The female germ cells in an embryo differentiate into
oogonia
What occurs IN UTERO for the oogonia
Starts meiosis I to become primary oocyte
What happens to the primary oocytes when puberty begins?
FSH stimulates a primary oocyte MONTHLY to finish Meiosis I, creating a secondary oocyte and the 1st polar body
What is the difference between a secondary oocyte and polar body?
Secondary oocyte takes most of the cellular material from primary oocyte, leaves polar body with only DNA
The secondary oocyte starts meiosis II and then
Ovulates
The only way for the secondary oocyte to finish meiosis II is ______. What is the product?
Fertilization
Zygote and 2nd polar body
GnRH stimulates the release of what 4 hormones in men?
FSH
LH
Testosterone
Inhibin
In men, FSH triggers
Sertoli cells release ABP (androgen binding protein) which stimulates sperm production
In men, LH triggers
Interstitial cells produce testosterone
In men, testosterone triggers
Increased sperm production
If sperm count is too high, ________ inhibits _______
Inhibin inhibits FSH
All 4 hormones triggered by GnRH are controlled by
Negative feedback
GnRH stimulates the release of what 4 hormones in women?
FSH
LH
Estrogen
Progesterone
In women, FSH triggers
Ovarian follicular cells to develop an ovum as well as produce estrogen
In women, LH triggers
Ovulation (follicle bursts and becomes corpus luteum)
Corpus luteum produces progesterone
What is the role of estrogen and progesterone in hormone regulation?
Regulates secretions from hypothalamus and pituitary gland, also preps uterus for implantation
What are the phases of the Ovarian Cycle?
Follicular phase
Ovulation
Postovulatory phase
What are the phases of the Follicular phase in the ovarian cycle?
Menstrual (discharge menstrual fluid)
Preovulatory (1 follicle matures and “balloons” towards ovary surface and releases estrogen)
What triggers follicular development and maturation?
FSH
Define zona pellucida
“Zone of cells” surrounding egg for support
What fills the expanding mature follicle?
Estrogen rich fluid
What causes ovulation?
LH spike due to increase in estrogen
What weakens the ovary’s wall so that the egg can exit?
Collagenese
What sweeps up the egg into the fallopian tubes
Fimbriae
What 2 phases occur during the postovulatory phase of the ovarian cycle?
Luteal (Corpus luteum forms and produces progesterone)
Premenstrual (no fertilization = corpus luteum degrades = no progesterone = menstruation)
What are the 3 phases of the uterine cycle?
Menstruation
Proliferative phase
Secretory phases
Describe the menstruation phase of the uterine cycle
Drop in progesterone causes arterial constriction which kills endometrial cells
Blood, serous fluid, and endometrial tissue are discharged
Describe the proliferative phase of the uterine cycle
Increase in estrogen from follicles causes increased mitosis in stratum basale of endometrium = thickened
Describe the secretory phase of the uterine cycle
Progesterone stimulates secretory glands to fill endometrial tissue with fluid = thickened
What causes an erection?
Parasympathetic system triggers nitric oxide and acetylcholine secretion which causes arteries to dilate and fill with blood
What occurs during female sexual excitement
Inner vagina dilates
Labia minora is vasocongested
Vaginal transudate moistens vagina
What occurs during female sexual plateau
Uterus is vertical
Cervix withdraws
Orgasmic platform (lower vagina) constricts penis
Clitoris engorges and withdrawn under prepuce
What occurs during female orgasm
Orgasmic platform (lower vagina) contracts rhythmically
Peristaltic contractions in uterus
What are the 2 penis arteries? What are their purposes?
Dorsal - regular blood supply
Deep - supplies lacunae of corpora cavernosa with blood to erect penis
What types of nerves are in the penis
Tactile, pressure, and temperature
What are the 2 phases of ejaculation?
Emission - sympathetic nervous system propels sperm through ducts w/ added secretions
Expulsion - semen in urethra activates muscular contractions to release sperm
Describe the composition of semen:
60% ______
30% ______
10% ______
along with …
60% seminal vesicle fluid
30% prostatic fluid
10% sperm
AND
fructose, fibrinogen, prostaglandins, fibrinolysin, and spermine
What is the refractory period?
anywhere from 10 minutes to hours after orgasm where another erection is impossible
Describe fertilization
Acrosome of sperm digests zona pellucida of egg
Sperm proteins bind to egg receptors and eject nucleus
Egg completes meiosis II
Fertilization complete when chromosomes of both sex cells combine in nucleus of egg
An implanted zygote in the uterus produces what hormone?
Human Chorionic Gonadotropin (HCG)
What does HCG do for pregnancy?
Increases progesterone to maintain endometrium and prevents menstruation
Describe the hormone levels and sources in the 3 trimesters of pregnancy
1st trimester: corpus luteum releasing estrogen and progesterone while placenta develops
2nd trimester: placenta becomes main source of estrogen and progesterone as it grows and corpus luteum degrades
3rd trimester: All hormones come from placenta
After birth, what 2 hormones are released in response to suckling?
Prolactin - milk production
Oxytocin - milk ejection and emotional bonding
Describe prostate cancer:
Cause?
Symptoms?
Risk Group?
Cancer in prostate
Problems with urination, such as dribbling and issues starting/stopping
men over 65, African American men, family history
Describe Cervical cancer:
Cause?
Symptoms?
Risk Group?
Cancer of cervix due to HPV
Pain during sex, pelvic pain, unusual bleeding and discharge
HPV infected women, multiple sex partners, smokers, long term use of oral contraceptives
Describe Polycystic Ovary Syndrome:
Cause?
Symptoms?
Risk Group?
Hypersecretion of male hormones causes fluid filled sacs to develop on ovaries
Facial hair growth, infertility, irregular periods, pelvic pain, thinning hair
1 in 10 women, obese, family history
Describe Endometriosis:
Cause?
Symptoms?
Risk Group?
Endometrium grows outside uterus and sheds with each cycle, causing build up in abdominopelvic cavity
Pelvic pain, heavy periods, infertility
Women who never give birth, pelvic infections, family history
Describe Pelvic Inflammatory Disease:
Cause?
Symptoms?
Risk Group?
Infection in female reproductive tract which inflames the fallopian tubes (usually from chlamydia or gonorrhea)
Abdominal pain, fever, irregular discharge, infertility from scar tissue, increased risk of ectopic pregnancies
Under 25 with STD/STI, women with IUD, multiple sex partners
Describe Erectile Dysfunction:
Risk Group?
Inconsisent or complete inability to maintain erection
Older men, obesity, smokers, diabetes, certain medications (such as antidepressants), and drug/alcohol abuse
Describe Gonorrhea:
Cause?
Symptoms?
Treatment?
Common bacterial infection
Women often asymptomatic, burning urination, increased vaginal discharge, anal itching, soreness and bleeding, increased risk of PID in women
(Same symptoms as Chlamydia)
Treat with antibiotics
Describe Chlamydia:
Cause?
Symptoms?
Treatment?
MOST COMMON bacterial infection
Frequently asymptomatic, burning urination, increased vaginal discharge, anal itching, soreness and bleeding, increased risk of PID in women
(Same symptoms as Gonorrhea)
Treat with antibiotics
Describe Syphilis:
Cause?
Symptoms/Phases?
Treatment?
Bacterial infection which can be fatal if untreated
Primary stage: painless sores at infection site
Secondary stage: rash, swollen lymph nodes, fever
Latent stage: no symptoms
Tertiary stage: systemic infections that affect other major organs, fatal
Treat with antibiotics (penicillin)
Describe Human Papilloma Virus (HPV):
Cause?
Symptoms?
Treatment?
High risk strain of virus increases risk of cancer
Low risk strain of virus = gential warts
MOST COMMON VIRAL STI
Prevent with vaccines and yearly screenings
Describe Genital Herpes:
Cause?
Symptoms?
Treatment?
Viral STI
HSV I = cold sores
HSV II = genital herpes
Painful, itchy blisters, occur several times per year, sometimes asymptomatic but still highly infectious
