Anatomy reproductive system Flashcards
(124 cards)
1
Q
What is reproduction?
A
Single-cell replication of genetic material
Allows organism growth and duplication
2
Q
What are gonads and their function?
A
Testes (males) and ovaries (females)
Produce gametes (sperm and eggs)
3
Q
Describe the scrotum and its function.
A
Outpouching of abdominal wall
Contains testes
Made of loose skin, muscle, and fascia
Divided into two compartments by scrotal septum
Keeps testes at cooler temp (~3°F cooler than body) for sperm production
Can hang lower or pull closer to body to regulate temperature
4
Q
What happens if testes don’t descend?
A
Testes develop in abdominal cavity, descend during last trimester
Cryptorchidism = testes fail to descend
Requires surgery to move testes to scrotum
If untreated, risk of testicular cancer increases
Testicular cancer common in young males (teens–20s)
5
Q
What is the median raphe?
A
External seam along the midline of the scrotum
Visible line where scrotal sac fused during development
Common site for vasectomy incision
6
Q
Describe the dartos muscle and its function.
A
Smooth muscle fibers in scrotal septum and under skin
Lies deep to the skin of scrotum
Controlled by autonomic nervous system
Contracts to shrink scrotal size (retracts scrotum) when temperature rises
Helps maintain optimal temperature for testes by retracting or relaxing
7
Q
Describe the testes and their main function.
A
Paired, oval-shaped glands inside the scrotum
Responsible for sperm production
8
Q
What is the tunica albuginea?
A
Dense fibrous connective tissue covering the testes
Divides testes into lobules via internal septa
Appears as the outer white layer of the testes
9
Q
Where are sperm stored prior to ejaculation?
A
Stored in the ampulla (not the epididymis) before ejaculation
10
Q
Outline the pathway sperm take starting at production.
A
Produced in seminiferous tubules
Move to straight tubule
Then to rete testis
Into efferent ducts
Finally to ductus epididymis where maturation begins
11
Q
Describe the ductus epididymis.
A
Also called epididymis
~20 feet long tightly coiled tubule
Sperm travel through here to the vas deferens
Lined with pseudostratified columnar epithelium with cilia and smooth muscle
Cilia move sperm forward since sperm are immobile inside the body
12
Q
Describe the ductus deferens (vas deferens).
A
Tube connecting epididymis to ampulla behind bladder
About 15–18 inches long
Ascends from scrotum → through inguinal canal → pelvic cavity
Loops over bladder to enter prostate via ejaculatory duct
13
Q
What structures are contained in the spermatic cord?
A
Ductus deferens
Autonomic nerves
Veins & arteries (pampiniform plexus)
Lymphatics
Surrounded by cremasteric muscle which adjusts testis position for temperature control
14
Q
What does the cremasteric muscle do?
A
Surrounds testes and spermatic cord
Elevates or lowers testes to maintain constant temperature
15
Q
Explain the vasectomy procedure briefly.
A
Vertical cut made
Vas deferens pulled out and cut (~1 cm section removed)
Ends prevented from reconnecting to stop sperm transport
16
Q
What are the two parts of the male urethra?
A
Prostatic urethra
~1 inch long
Passes through the prostate gland (walnut-sized, donut-shaped)
Hole in the middle for urine and sperm flow
Penile urethra
~6 inches long
Includes membranous part and runs through the penis
17
Q
What are the main functions of the penis?
A
Urination
Introduction of sperm into the vagina during intercourse
18
Q
Name the three main compartments in the penis.
A
Dorsal vein (1)
Corpora cavernosum (2) — engorge with blood during arousal, become firm
Corpora spongiosum (1) — surrounds urethra, less firm, forms the glans penis
19
Q
How do the penile compartments fill during an erection?
A
Sexual stimulation → all three compartments fill with blood
Veins vasoconstrict (reduce outflow)
Arteries vasodilate (increase inflow) → erection occurs
20
Q
What is the glans penis?
A
Distal (tip) end of the penis
Enlarged end of the corpora spongiosum
21
Q
What is the prepuce or foreskin?
A
Skin covering the glans penis
Removed during circumcision
22
Q
Where does sperm production occur?
A
In the seminiferous tubules of the testes
23
Q
Function of Interstitial Cells of Leydig?
A
Produce testosterone
23
Q
Describe spermatogonia.
A
Most immature sperm cells
Located along the basement membrane of seminiferous tubules
Constantly dividing (highly mitotic) to provide new sperm cells
24
List the stages of sperm development in order.
Spermatogonia → Primary spermatocytes → Secondary spermatocytes → Spermatids → Spermatozoa
25
What happens in primary and secondary spermatocytes?
Primary spermatocytes: Undergo meiosis I
Secondary spermatocytes: Undergo meiosis II, leading to spermatids (haploid, 23 chromosomes)
26
Describe spermatids.
Haploid cells with 23 chromosomes
2nd to last stage before maturing into spermatozoa with flagella
27
Describe spermatozoa.
Mature sperm cells
About 300 million produced daily
Survive ~48 hours in female reproductive tract
28
What is the function of Sertoli cells?
“Nurse” or sustentacular cells
Support and nurture developing sperm
Protect sperm from autoimmune attack by isolating them from the body’s immune system
29
What is the acrosome and its function in sperm?
Contains hyaluronic acid enzyme
Enzyme breaks down hyaluronic acid to help sperm move toward the egg
Located on the head of the sperm
30
Describe the main parts of sperm.
Head: contains genetic material (nucleus)
Neck
Midpiece: packed with mitochondria for energy
Tail: formed from microtubules, propels sperm forward
31
What is the general function of the male accessory glands?
Secrete the liquid portion of semen
32
What do seminal vesicles secrete and why?
Secretes an alkaline viscous liquid rich in fructose (60% of seminal volume)
Alkaline to neutralize acidic vagina to protect sperm
33
Describe the prostate gland and its secretion.
Chestnut-sized, donut-shaped gland at base of urinary bladder
Secretes an alkaline fluid making up 13-33% of seminal volume
Ejaculatory duct ends here, connecting to prostatic urethra
34
What is the role of the Bulbourethral glands?
Pea-sized glands below prostate
Secrete mucous (pre-ejaculatory fluid) for lubrication of urethra
35
What is semen and what are its properties and functions?
Mixture of sperm + secretions
Volume: 2.5–6 mL
pH: 7.35–7.50 (basic)
Functions:
Transport medium and nutrition
Capacitation (enzymatic activation of sperm)
Seminalplasmin (antibacterial)
36
What hormones does the anterior pituitary produce and their roles?
FSH (Follicle Stimulating Hormone): initiates spermatogenesis and sperm maturation
ICSH (Interstitial Cell Stimulating Hormone or LH): stimulates Leydig cells to produce testosterone
37
What are the main functions of testosterone?
Controls growth, development, and maintenance of sex organs
Stimulates bone growth and protein anabolism
Involved in sexual behavior and sperm maturation
Develops secondary sex characteristics:
Increased body hair
Increased muscularity
Enlarged thyroid cartilage
38
What effect does steroid use have on the testes?
Causes shrinkage of testes because external testosterone signals brain to stop natural testosterone production in testes
Steroids increase muscle mass and bone density (anabolic effect)
39
What is the role of androgen binding hormone?
Helps with proper sperm development
40
What are the main functions and location of the ovaries?
Paired glands located in the upper pelvic cavity on each side of the uterus.
Produce eggs and female hormones.
41
What are the two ligaments anchoring the ovary and their functions?
Ovarian ligament — attaches ovary to uterus
Suspensory ligament — attaches lateral surface of ovary to lateral pelvic wall; suspends ovary superior and lateral
42
What is the function and length of the uterine (fallopian) tubes?
Muscular tubes that transport eggs to the uterus.
Approximately 5 inches long.
42
What are the infundibulum and fimbria, and their roles in egg transport?
Infundibulum: expanded distal end closest to ovary.
Fimbria: finger-like projections at infundibulum that catch the egg during ovulation and help guide it into the tube.
43
What is an ectopic pregnancy, and how can it relate to the fallopian tubes?
Occurs when the egg implants outside the uterus, often in the fallopian tubes due to egg entering the peritoneal space. Commonly caused by pelvic inflammatory disease (PID).
44
Where does fertilization usually occur, and how long does the egg take to reach the uterus?
Fertilization usually occurs in the lateral third of the fallopian tube.
Egg transport to uterus takes 3-4 days.
45
What is the shape and normal position of the uterus?
Small, pear-shaped organ.
Normally antiflexed, bending anteriorly over the bladder.
46
What are the three ligaments that anchor the uterus and their functions?
Broad ligament: extensive mesentery covering uterus and ovaries (double-layered peritoneum).
Round ligament: arises lateral uterus, connects to external genitalia, travels laterally.
Lateral ligament: connects uterus to lateral pelvic wall.
47
What is the fundus of the uterus?
Dome-shaped region above the fallopian tubes.
Projects upward above the body of the uterus.
48
What are the three main layers of the uterus wall?
Endometrium: mucosa and lamina propria (inner lining)
Myometrium: thick, smooth muscle layer
Serosa: visceral peritoneum (outer layer)
49
What is the vagina, its length, and typical pH range?
Muscular tube extending from the cervix to the external genitalia.
Approximately 3-4 inches long.
pH ranges from 3.5 to 4.5, can go up to 6.
50
What is the fornix in the vagina?
A shallow recess around the periphery of the cervix inside the vagina.
51
What composes the vaginal walls, and what happens during sexual arousal?
Vaginal walls have blood vessels, layers of smooth muscle, and are moistened by cervical and gland secretions.
During sexual arousal, increased blood flow causes plasma components to sweat into the vaginal vault (lubrication).
52
What is the hymen and what can happen to it?
Thin epithelial fold partially or completely blocking the vaginal entrance.
Can be torn by physical or sexual activity; absence doesn’t necessarily indicate sexual intercourse.
53
What is the vulva?
Collective term for the female external genitalia.
54
What is the mons pubis?
Elevation of adipose tissue covered by pubic hair over the pubic symphysis.
A thick, fatty area at the top of the symphysis pubis.
55
What are the labia majora and what is their homologous male structure?
Outer longitudinal skin folds extending inferiorly from mons pubis.
Contain fat, sebaceous glands, sweat glands, and hair.
Homologous to the male scrotum.
56
What are the labia minora?
Inner, thinner folds of skin medial to labia majora.
Two folds, no adipose tissue or hair.
Contain sebaceous and sweat glands.
Secrete sebum from sebaceous glands.
57
What is the clitoris and its male homologous structure?
Small mass of erectile tissue at anterior junction of labia minora.
Homologous to the male penis.
58
What is the prepuce of the clitoris?
Part of the labia minora that covers the clitoris.
59
What is the vestibule in the female genitalia?
Cleft or space between the two labia minora.
60
Where is the vaginal orifice located?
Posterior to the urethral orifice.
60
Where is the urethral orifice located?
Inferior and posterior to the clitoris, between the labia minora.
61
Where are Skene’s glands and what do they do?
Located on either side of the urethral orifice.
Secrete mucus during sexual arousal, adding to vaginal lubrication.
62
Where are Bartholin’s glands and what is their function?
Located on either side of the vaginal orifice.
Secrete mucus for lubrication.
Homologous to male Cowper’s glands.
63
What are the menstrual and ovarian cycles?
Two simultaneous cycles: menstrual cycle (uterine lining changes) and ovarian cycle (egg maturation and release).
64
What happens during the ovarian cycle?
Series of events over ~28 days related to maturation and release of the ovum (egg).
Oogenesis = formation of the female ovum.
65
What is menarche?
The first occurrence of menstruation.
Now happens earlier due to hormones in food and increased obesity rates.
Delayed in athletes with low body fat (e.g., gymnasts, runners).
66
What is the Female Athlete Triad Syndrome?
Disorder involving loss of estrogen due to eating disorders and low body fat, affecting menstrual cycles.
67
What is menopause?
Cessation of menstruation, typically between ages 45-55.
Lasts about 5-10 years.
68
What happens during primary follicle development in days 1-5 of the ovarian cycle?
~25 primary follicles begin development (follicles existed before birth)
Follicles house eggs and produce low levels of estrogen
Zona pellucida (clear membrane) forms around ova
Follicle cells start secreting estrogen
Stimulated by FSH released from anterior pituitary due to FSHRF from hypothalamus
69
What occurs during secondary follicle development?
Few primary follicles survive; others degenerate
Larger follicle forms with thickening zona pellucida
Follicular fluid fills antrum (central cavity)
Estrogen production increases
70
What happens during the follicular phase (days 6-13) in the ovarian cycle?
One follicle matures into Graafian follicle, others undergo atresia
Large fluid-filled antrum (liquor folliculi) forms
Follicle migrates to ovary surface preparing for ovulation
FSH is dominant, but LH increases toward ovulation
71
What are menarche and menopause?
Menarche: first menstrual cycle (ages 11-13)
Menopause: last menstrual cycle (ages 40-55) due to decreased ovarian estrogen
72
What changes occur after ovulation in the ovarian cycle?
Blood clot forms in empty follicle → corpus hemorrhagicum
Clot reabsorbs; follicular cells form corpus luteum (“yellow body”)
Corpus luteum secretes progesterone and some estrogen
Prepares endometrium for implantation
If no implantation: corpus luteum degenerates → corpus albicans (scar tissue)
If implantation: corpus luteum maintained by HCG for ~3 months to support embryo and maternal breast development
73
What triggers ovulation and when does it occur?
Huge LH surge triggers ovum release on day 14
Only one ovary ovulates each cycle
74
What is the menstrual cycle?
28-day cycle of growth and shedding of endometrium
Occurs simultaneously with ovarian cycle
Begins with menstruation (sloughing of endometrium) due to decreased estrogen/progesterone if no pregnancy
75
When do menstruation and ovulation occur in the cycle?
Menstruation starts day 1, lasts 3-5 days
Ovulation occurs day 14
76
How do estrogen and progesterone affect the endometrium during the menstrual cycle?
Estrogen (1st half): thickens endometrium for implantation
Progesterone (2nd half): maintains thickness, increases vascularity & secretory glands (glucose, glycogen production)
77
What are the phases of the ovarian cycle?
Follicular Phase (Days 1-14): follicle development and ovulation
Luteal Phase (Days 15-28): corpus luteum formation and hormone secretion
78
What happens during the menstrual phase (days 1–5)?
Shedding of the superficial endometrium
Menstrual flow includes blood, tissue fluid, mucus, epithelial cells
Triggered by decline in estrogen & progesterone
Lasts ~5 days
79
What characterizes the secretory phase (days 15–28)?
Progesterone from corpus luteum thickens endometrium further
Endometrial glands enlarge, secrete glycogen-rich mucus
Blood vessels elongate and twist (tortuous)
If no implantation → estrogen & progesterone drop → menstruation restarts
79
What occurs during the proliferative phase (days 6–13)?
Estrogen from developing follicles stimulates endometrial repair
Endometrium thickens in preparation for potential implantation
80
What are the suspensory ligaments of Cooper?
Collagen fibers running between skin and deep fascia
Support breast structure
Non-elastic; once stretched, do not return to original shape
81
How is the glandular tissue of the breast organized?
15–20 lobes per breast
Each lobe has smaller lobules
Lobules contain alveoli, which have the secretory milk-producing cells
82
What is the pathway of milk from alveoli to nipple?
Alveoli → Secondary Tubules → Mammary Ducts → Ampulla → Lactiferous Ducts → Nipple
83
What are Montgomery glands?
Small bumps on the areola
Sebaceous glands that secrete lubricating oil to condition the nipple
84
What is the let-down reflex and how is it triggered?
Suckling stimulates receptors in nipple & areola
Triggers oxytocin release from posterior pituitary
Oxytocin causes myoepithelial cells in ampulla to contract
Milk is ejected through ducts to nipple
85
What is the function of tubuloalveolar cells in the breast?
Specialized glandular cells in the alveoli
Responsible for producing milk during lactation
86
What is "development" in human reproduction?
A sequence of events starting with fertilization of the egg and ending with parturition (delivery).
87
What are gametes and their chromosome number?
Ovum (egg) and sperm
Haploid cells (23 chromosomes)
Created through meiosis
88
What is meiosis and its purpose?
Specialized cell division producing gametes with half the number of chromosomes (haploid, 23C).
89
How are monozygotic (identical) twins formed?
One egg is fertilized and later splits into two embryos
Genetically identical
89
What is fertilization?
The joining of sperm and egg to form a zygote
Zygote is diploid (46 chromosomes)
90
How are dizygotic (fraternal) twins formed?
Two eggs released and fertilized by two different sperm
Genetically unique, like regular siblings
91
What is cleavage in embryonic development?
Series of rapid mitotic cell divisions of the zygote
Ends upon contact with the uterine wall
92
When and what is implantation?
Adhesion of the blastocyst to the uterine wall
Occurs around Day 7 after ovulation (~Day 21 of the cycle)
93
What is the role of the syncytial trophoblast?
Outer layer of blastocyst that burrows into endometrium
Secretes hyaluronic acid to break down endometrial tissue
Envelops embryo for nutrient exchange
94
What do the 3 germ layers form?
Ectoderm: skin, nervous system (via neurulation), part of digestive & respiratory
Mesoderm: muscle, skeleton, heart, blood, kidneys, gonads
Endoderm: lining of digestive, respiratory, bladder, and gametes
95
What happens during gastrulation?
Cells from epiblast migrate through primitive streak
Form the 3 germ layers: ectoderm, mesoderm, endoderm
96
What is neurulation?
Embryological process where the ectoderm gives rise to the central nervous system
97
When does organogenesis occur and what happens?
Begins in Week 4
Embryo is about 5 mm
Arm and leg buds start to form
98
What is the difference between an embryo and a fetus?
Embryo: 0–3 months of development
Fetus: 3–9 months of development
99
Who produces progesterone in early vs. late pregnancy?
First trimester: Corpus luteum produces progesterone
After 1st trimester: Placenta takes over hormone production (estrogen + progesterone)
100
What is the yolk sac and its function?
First extra-embryonic membrane to appear
Initial site of blood cell formation
Yellow in appearance
101
What is the amnion and what does it do?
Formed from mesoderm and ectoderm
Produces amniotic fluid – cushions and hydrates embryo
Forms the amniotic sac, which must rupture before birth ("water breaking")
102
What is the function of the allantois?
Outpouching from endoderm of yolk sac
Helps form the urinary bladder
103
What is the chorion and its role?
Lies outside the amnion
Transports nutrients and oxygen between embryo and trophoblast
Forms chorionic villi → become part of the placenta
104
How does the placenta form?
Formed where chorionic villi remain in contact with decidua basalis
Blood vessels form close to maternal vessels for gas & nutrient exchange
104
What are chorionic villi and what do they form?
Finger-like projections from the chorion
Invaginate into the endometrium
Site where placenta develops
105
What are the decidua basalis and capsularis?
Basalis: Endometrium beneath embryo; becomes placenta
Capsularis: Thin endometrium surrounding the floating chorion
106
What does HCG do in early pregnancy?
Maintains corpus luteum to produce progesterone
Secreted by syncytial trophoblast
Detected at end of menstrual cycle to confirm pregnancy
106
What are the blood vessels in the umbilical cord?
2 umbilical arteries: Carry deoxygenated blood from fetus to placenta
1 umbilical vein: Carries oxygenated blood from placenta to fetus
107
What is placenta previa and why is it dangerous?
Placenta implants too low, near or over cervix
Baby may not get blood supply if placenta is delivered first → requires C-section
108
What is placental abruption?
Placenta detaches prematurely from the endometrium
Can result in loss of fetal oxygen supply → emergency delivery
109
What are the main functions of the placenta?
Supplies oxygen and nutrients to fetus
Removes CO₂ and waste
Produces estrogen, progesterone, and HCG
110
What does parturition mean?
Expulsion of the fetus (childbirth)
111
What occurs during the dilation stage of labor?
Cervix dilates to 10 cm and becomes 100% effaced (thinned)
Can last 8–14 hours
Uterine lining pulled up over the baby’s head
112
What is the afterbirth?
The expelled placenta after the baby is born
113
What happens during the expulsion stage?
Delivery of the baby
Lasts ~45 minutes
Pushing starts after full dilation
114
What happens during the placental stage of labor?
Uterine contractions eject the placenta
Occurs 20–40 minutes after delivery of the baby
115
What is the role of oxytocin during labor?
Released by posterior pituitary
Triggered by high estrogen and uterine stretching
Stimulates strong uterine contractions
Also responsible for milk let-down reflex
116
What do prostaglandins do during labor?
Back:
Cause smooth muscle contractions in the uterus
Help intensify uterine contractions
117
What is the function of relaxin during pregnancy and delivery?
Softens ligaments throughout the body
Especially important in pelvic region to allow fetal passage
Secreted by the placenta
