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BIOM 3200 > Reproduction > Flashcards

Reproduction Flashcards

1
Q

Identify and describe the internal and external genitalia of the female and male reproductive systems.

A

Female Reproductive System:
-Internal Genitalia: 2 ovaries, 2 uterine tubes, uterus, cervix, and vagina
-Ovaries: small, oval-shaped
organs located on either
side of uterus
-Uterine Tubes: provide
connection between
ovaries and uterus
-Uterus/Womb: pear-
shaped muscular organ
-Cervix: uterus narrows to
form cervix, closed, except
during ovulation and
childbirth
-Vagina: copulatory organ
and birth canal during
parturition
-External Genitalia/Vulva: vestibule, labia majora, labia minora and clitoris
-Vestibule: longitudinal cleft
surrounded by the labia
majora where the urethra
and vaginal opening are
found
-Clitoris: same embryonic
origin as penis, erectile
tissue, very sensitive to
physical stimulation
-Labia Majora/Minora:
longitudinal folds that cover
opening of vagina and
urethra
Male Reproductive System:
-Testes: located in individual sacs and together form scrotum, production of sperm and sex hormones
-from testes, sperm follows
series of ducts (epididymis,
vas deferens, ejaculatory
duct) to arrive in urethra
-along ductal system are
accessory organs:
ampullae, seminal vesicles,
prostate and bulbo-urethral
gland
-urethra continues through
penis
-Penis: made of 3 erectile bodies, and is enlarged to form glans penis
-glans and shaft are the
penis is covered by skin
known as the prepuce or
foreskin

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2
Q

Differentiate between primordial, primary, secondary, tertiary (mature/graffian) ovarian follicles.

A

Primordial Follicle: single layer of follicular cells surround ovum
Primary Follicle: follicle begins to grow; supporting cells become cuboidal and the number of cell layers around the ovum increases
Secondary Follicle: follicular cells begin to differentiate into theca and granulosa cells, and a fluid-filled vesicle begins to develop inside the follicle
Tertiary/Mature/Graffian Follicle: fluid-filled vesicles has developed into antrum; granulose cells have formed a stalk-like projection (cumulus oophorus)

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3
Q

Discuss the 2 possible fates of ovarian follicles: ovulation and atresia.

A

-during each ovulatory cycle only 1 follicle will develop into fully mature follicle
-this follicle will go on to be ovulated from ovary into uterine tube
-remaining secondary follicles will undergo atresia
Atresia: form of apoptosis, removing secondary follicles from ovary

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4
Q

Define granulosa, theca, zona pellucida, corona radiata and cumulus oophorus.

A

Granulosa Cells: type of follicular cell that forms the innermost layers of the follicular wall
Theca Cells: type of follicular that form the periphery of the follicle
Zona Pellucida: thin, gel-like layer of proteins and polysaccharides found between the oocyte and the corona radiata
Corona Radiata: ring of granulosa cells found around the oocyte
Cumulus Oophorus: stalk-like projection of granulosa cells that supports the oocyte

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5
Q

Identify the 3 segments of the oviduct.

A

Oviduct (Uterine Tubes): divided into infundibulum, ampulla and isthmus
-Infundibulum: cone-shaped structure in close relation to ovaries, opening of the uterine tube
-Ampulla: follows and contains many folds in its lining; to slow ovum movement, where fertilization occurs
-Isthmus: connects the oviduct to the uterus via the uterotubal junction

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6
Q

Describe the function of the secretory columnar cells of the oviduct.

A

Secretory Columnar Cells: produce liquid that facilitates movement of ova and sperm through oviduct; provide nutrition to early embryo, helped protect egg and sperm from immune system

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7
Q

Discuss the function of the frimbria and cilia of the oviduct.

A

Fimbriae: found in infundibulum of oviduct, act to move ovulated oocyte from ovary into oviduct
Cilia: found in ampulla and isthmus, help to move liquid in oviduct and oocyte/embryo towards uterus
-prevent microorganisms from moving towards ovaries

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8
Q

Describe how oocytes and spermatozoa are transported down the oviduct.

A

Oviduct is muscular organ; peristalic contractions of the oviductal smooth muscles along with the cilia help to facilitate the movement of the movement of oocyte and sperm down the oviduct

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9
Q

Identify the perimetrium, myometrium and endometrium of the uterus.

A

Permetrium: outermost layer of uterus; connective tissue
Myometrium: middle layer of uterus; multiple layers of smooth muscle and is thickest near fundus/uterine horn and thinnest near cervis
Endometrium: innermost layer of uterus; muscosal lining of uterus that thicken to prepare for implantation and is sloughed off during menses

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10
Q

Describe the cervix and indicate its function.

A

Cervix: narrowing of uterus, opening into vagina
-mainly made of connective tissue and small amount of smooth muscle
-closed except during ovulation (slight relaxation) and parturition (dilation)
-secretes mucus that forms plug in cervical lumen

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11
Q

Identify an ectopic pregnancy.

A

Ectopic Pregnancy: fertilized egg implants itself in uterine tube or outside of reproductive system; in abdominal or pelvic cavity
-doesn’t result in fetus developing to term

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12
Q

Identify the 3 functions of the male reproductive tract.

A

-secretion of sex hormones
-production of sperm
-deposition of sperm into female reproductive tract

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13
Q

Describe the anatomy of the testes.

A
  1. 2 tissue layers: thing serosa tunica vaginalis and tunica albuginea surround testes
  2. Tunica Albugenia: inserts into testis and divides it into smaller lobules
    -each lobule is made of seminiferous tubules
    -seminiferous tubules surrounded by connective tissue containing scattered, testosterone producing Leydig cells
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14
Q

Differentiate between a Sertoli and Leydig cell and indicate their functions.

A

Sertoli Cells: found within seminiferous tubules and respond to FSH activation
-able to produce inhibin (hormone that inhibits further FSH secretion)
-thought to be involved in conversion of spermatids to spermatozoa and help to make seminiferous tubules site of immune privilege
Leydig Cells: found in interstitial space between seminiferous tubules
-able to respond to LH; production of testosterone

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15
Q

Define: epididymis, spermatic cord, efferent ductules, rete testes, seminiferous tubules, gubernaculum, cremaster muscle, tunica vaginalis, tunica albuginea.

A

Epididymis: tightly coiled structure lying about the testis; sperm passes from seminiferous tubules in epididymis
Spermatic Cord: cord-like structure that consists of vas deferens and surronding tissues
Efferent Ductules: connect the rete testis to epididymis
Rete Testes: series of fine collecting tubules that testes drain into
Seminiferous Tubules: densely coiled tubules located within testes that is location of sperm development
Gubernaculum: anchors the testes and epididymis to scrotum
Cremaster Muscle: responsible for suspension of testes; cold causes muscle to contract and move testes closer to body
Tunica Vaginalis: thin, serosal layer surrounding each testis
Tunica Albuginea: tough, fibrous layer surrounding each testis

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16
Q

Identify 3 regions of the epididymis: caput, corpus, cauda.

A

Caput: head of epididymis, receives sperm from testis
Corpus: body of epididymis
Cauda: tail of epididymis, storage of sperm until ejaculation

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17
Q

Indicate how the epididymus contributes to the formation of spermatozoa.

A

-spermatozoa that enters epididymis are non-motile
-as they move through epididymis, undergo maturation to become more resistant to changes in pH and temperature
-upon combination with prostatic fluids during ejaculation; sperm are motile and able to fertilize ovum

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18
Q

Identify male accessory sex glands including: seminal vesicles, prostate, bulbourethral gland.

A

Seminal Vesicles: paired organs that secrete fluid containing fructose into ejaculatory duct used as energy source for sperm; androgen-dependent accessory organ
Prostate Gland: gland found where ejaculatory duct merges with urethra; fluid from prostate enters urethra through pores and contains citric acid, calcium and coagulation proteins
Bulbourethral Gland: small gland found below prostate; secretion form pre-ejaculate that helps lubricate urethra for sperm passage and removes traces of acidic urine

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19
Q

Describe the route sperm take from the seminiferous tubule to the external urinary meatus.

A

Seminiferous tubules -> rete testis -> efferent ductile -> epididymis -> vas deferens -> ejaculatory duct -> prostatic urethra -> penile urethra

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20
Q

Identify the 3 erectile bodies of the penis.

A

-paired corpora cavernosa (2) on dorsal aspect of penis
-corpus spongiosum on ventral side

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21
Q

Describe how the anatomical arrangement of the erectile bodies, tunica albuginea, ischiocavernosus muscle and bulbospongiosus muscle result in an erection.

A

-erection is achieved by increasing blood flow to erectile tissues and a fibrous, non-stretchable capsule (tunica albuginea) surrounds these tissues
-corpora cavernosa are embedded by ischiocevernous muscle
-contraction of the muscles increases blood flow into corpora cavernosa leading to erection
-bulbospongiosum muscle embed the corpus spongiosum
-contraction of these muscles leads to constriction of urethra aiding in ejaculation and urination

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22
Q

Briefly describe how parasympathetic stimulation leads to an erection.

A

-parasympathetic nerve stimulation leads to vasodilation or arterioles leading into corpora cavernosa; increased blood flow to region
-action believed to be mediated by nitric oxide (NO) release from parasympathetic nerve terminals

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23
Q

Identify major anatomical sections of a spermatozoon.

A

-head, midpiece, principal piece, and end piece
Head: contains genetic information (covered by acrosome)
Midpiece: contains mitochondria
Principle and Endpiece: make up flagellum

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24
Q

Briefly describe spermatogenesis in regards to meiotic divisions.

A

Spermatogenesis begins with mitotic division of spermatogonia (2n); production of speratogonia (2n) and primary spermatocyte (2n).
Primary spermatocyte will undergo 2 meiotic divisions that will produce 4 spermatids (n) with half of genetic information of original primary spertocyte.

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25
Q

Differentiate between primary spermacyte, secondary spermacyte, spermatids and spermatozoa.

A

Primary Spermatocyte: derived from mitotic division of spermtogonia; contains full complement of 46 chromosomes (2n)
Secondary Spermatocyte: derived from first meiotic division (of a primary spermatocyte); cells only contain one of each homologous pair and are therefore haploid (23 chromosomes, n)
Spermatids: derived from second meiotic division (of a secondary spermatocyte); each cell contains one chromatid of each chromosome (haploid, n)
Spermatozoa: mature form of sperm; 23 chromosomes (n) and a change in structure to head and tail structure

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26
Q

Describe the process of spermiogenesis.

A

Spermiogenesis: process of conversion of immature spermatids to mature spermatozoa

27
Q

Describe the role of Sertoli cells on spermatogenesis and spermiogenesis.

A

During spermatogenesis, Sertoli cells act to nourish the developing sperm and are known as nurse cells. During spermiogenesis, more of spermatid cytoplasm is lost; done by phagocytosis of residual bodies of cytoplasm from spermatid by Sertoli cells.

28
Q

Describe the role of FSH, LH and testosterone on spermatogenesis.

A

FSH: not absolutely required for spermatogenesis; acts as enhancer, required for maximal sperm production and perhaps optimal fertility
LH: needed to stimulated production of testosterone by Leydig cells
Testosterone: needed to complete meiotic division and form early stages of spermatid maturation

29
Q

Describe the hypothalamic-pituitary-gonagal (HPG) axis in males.

A

-hypothalamus secretes gonadotropin-releasing hormone
-GnRH feeds into anterior pituitary to facilitate release of FSH and LH
-FSH acts on Sertoli cells of testes and leads to production of inhibin
-inhibin is able to feedback onto anterior pituitary to inhibit further release of FSH
-LH acts on Leydig cells of testes and leads to production of testosterone
-testosterone can feedback onto hypothalamus and anterior pituitary to inhibit further release of GnRH and LH

30
Q

Identify the non-reproductive functions of testosterone and other androgens.

A

-growth of testes, pubic and axillary hair, body growth, growth of penis, lowering of voice, facial hair and sweat glands
-fetal testosterone is believed to be important in sexual differentiation of the male and female brains

31
Q

Describe the role of alpha reductase and aromatase on testosterone biology and formation of active metabolites.

A

-testosterone can be metabolized via 2 pathways: 5α-reduction or aromatization
-activation of the 5α-reduction pathway leads to the production of dihydrotestosterone (DHT), a potent androgen
-DHT can be further metabolized to androstanediol (3α-diol and 3β-diol)
-aromatization pathway is facilitated by the enzyme aromatase and leads to conversion of testosterone to 17β-estradiol

32
Q

Discuss the role of inhibin during HPG negative feedback.

A

-inhibin is secreted by Sertoli cells in males and by granulosa cells in females
-inhibin is able to inhibit FSH secretion from the anterior pituitary without affecting LH secretion

33
Q

Describe the HPH axis in females.

A

-GnRH is released from the hypothalamus, which feeds onto the anterior pituitary
-anterior pituitary is induced to release LH and FSH
-LH and FSH induce the release of estradiol, progesterone and inhibin from the ovaries
-estradiol and progesterone can feedback onto the hypothalamus and anterior pituitary to inhibit further hormone release
-inhibin can feedback onto the anterior pituitary to inhibit further FSH release

34
Q

Discuss the glycoprotein family of pituitary hormones including similarities in structure.

A

-glycoprotein family of pituitary hormones includes LH and FSH, TSH and ACTH
-composed of a common alpha subunit and a different beta subunit to form a heterodimeric molecule

35
Q

Describe how the pulsatile secretion of GnRH can influence gonadotropin secretion.

A

-pulsatile secretion of GnRH is needed to precent receptor desensitization
-to influence which anterior pituitary hormone is preferentially secreted
-high frequency, high-amplitude secretion is believed to mainly stimulate LH secretion
-low-frequency secretion is through to stimulate FSH secretion

36
Q

Relate GnRH pulses to specific stages of the ovarian cycle.

A

-low-frequency pulses expected during the early follicular phase when FSH levels are higher than LH levels
-prior to ovulation, GnRH pulses would be high-frequency and amplitude to stimulate the LH surge

37
Q

Describe the effects of FSH and LH on ovarian follicle development and ovarian hormone secretion.

A

-growth of ovarian follicles is stimulated by and dependent upon FSH secretion
-FSH is highest at the beginning of the follicular phase and stimulates FSH receptors in the granulosa cells to stimulate follicle growth and estradiol secretion
-LH levels rise throughout the follicular stage and surge just prior to ovulation
-LH is important for development of the corpus luteum during the luteal phase

38
Q

Describe the 2 cell, 2 gonadotropin theory of ovarian steroid production.

A

-2 types of cells exist in ovarian follicles, granulosa cells and theca cells
-theca cells have LH receptors and are responsible for the production of androgens and progesterone
-granulosa cells are able to repsond to FSH and produce estradiol via the conversion of androgens to estrogens by the use of the enzyme aromatase

39
Q

Discuss the proliferative, secretory and menstrual phases of the estrous/menstrual cycle.

A

-proliferative, secretory and menstrual phases of the cycle are in relation to changes in the endometrial lining of the uterus
-first 4 days of the cycle (follicular phase) is the menstrual phase as the endometrium is being shed
-remainder of the follicular phase as well as during ovulation is known as the proliferative phase
-endometrial layer is
thickening and developing
spiral arteries
-secretory phase falls in line with the luteal phase
-hormonal secretion from the corpus luteum stimulates the development of uterine glands as the endometrium becomes prepared to accept an embryo should fertilization occur

40
Q

Describe the effects of estrogens on the uterus, oviduct, breasts, skeleton and fat deposition.

A

-estrogens are able to stimulate an increase in ciliated cells in the oviduct, and increase its vascularization and secretion
-estrogen is involved in the development of spiral arteries in the endometrial layers as it thickens
-estrogens also stimulates the growth of the breasts beginning at puberty
-estrogen stimulates the epiphyseal growth plates leading to a growth spurt at puberty as well as bone mineralization by stimulating osteoblasts and inhibiting osteoclasts

41
Q

Describe the effects of progesterone on the uterus, oviduct and breasts.

A

Progesterone is important for the enhanced vascularization of the endometrium during the secretory phase, as well as stimulating breast growth at puberty.

42
Q

Discuss the negative feedback of the HPG axis in females during the estrous/menstrual cycle.

A

-negative feedback is primarily seen in the luteal phase
-estrogen and progesterone, secreted from the corpus luteum, act on the hypothalamus and anterior pituitary to inhibit further secretion of GnRH and LH/FSH
-eventually lead to a decrease in estrogen and progesterone levels

43
Q

Discuss how feedback control is altered during the LH stage.

A

-LH surge is facilitated by positive feedback control
-as estradiol levels rise, they feedback onto hypothalamus; leads to an increase in the frequency of GnRH pulses
-estradiol also enhances the ability of the anterior pituitary to respond to GnRH
-leads to the surge in the release of LH (and FSH somewhat) from the anterior pituitary

44
Q

Describe the LH surge and indicate its downstream effects.

A

LH surge begins approx. 24 hours before ovulation and peaks 16 hours prior to ovulation.

45
Q

Describe ovulation.

A

LH surge leads to the rupture of the mature Graafian follicle and a secondary oocyte is released from the ovary. It is swept into the oviduct.

46
Q

Identify hormonal changes in FSH, LH, progesterone and estrogen during the estrous/menstrual cycle.

A

FSH: FSH levels are high at the beginning of the cycle and slowly decrease throughout the follicular phase
-small surge just prior to ovulation
-levels remain low throughout the luteal phase until just prior to the start of the next cycle
LH: remain fairly constant through the follicular phase, and then surge just prior to ovulation
-fall off sharply after the surge and remain fairly constant throughout the luteal phase
Estrogen: climb throughout the follicular phase due to the growing follicle and peak just prior to ovulation
-falls off sharply to begin the luteal phase, but then peak again mid luteal phase due to estrogen secretion from the corpus luteum
Progesterone: negligible during the follicular phase, but rise rapidly to peak mid-way through the luteal phase due to secretion from the corpus luteum

47
Q

Identify all 4 phases of the estrus/menstrual cycle.

A

Menstrual cycle is divided into 2 follicular phases; menstrual and proliferative; and ovulatory and luteal phases. In animals, the estrous cycle is divided into 4 stages: proestrus, estrus, meletrus, and diestrus.

48
Q

Describe changes to gonadotropin secretion, ovarian hormone secretion and uterine changes during the 4 stages of the estrus/menstrual cycle.

A

Follicular (day 1-4): low LH and FSH, low progesterone and estrogen; primary follicles grow, loss of outer 2/3 of endometrial lining
Follicular (day 5-13): FSH levels slightly higher than LH, estrogen levels rise; development of 1 mature graafian follicle, endometrium begin to thicken
Ovulatory (day 14): LH surge, small FSH increase as well, estrogen levels fall; follicle rupture to release oocyte, no changes in endometrium
Luteal (days 15-28): LH and FSH decrease (negative feedback), estrogen and progesterone increase then decrease corpus luteum formed; regression late in phase, glandular development in endometrium

49
Q

Discuss the effects of body fat, pheromones and stress on female reproduction.

A

-GnRH release itself is influenced by gonadal hormones as well as signals for higher order brain regions
-neurons of the limbic system can also feed onto the hypothalamus
-limbic system is involved in stress and emotion, and high levels of stress can lead to cessation of menstruation
-women with low body fat may have irregular cycles or cease menstruating; due to lack of leptin secretion from adipocytes

50
Q

Describe how the contraceptive pills inhibits fertilization and successful pregnancies.

A

-contraceptive pills often contain synthetic forms of estrogen and progesterone
-lead to elevated levels of estrogen and progesterone in the blood, resulting in negative feedback to the hypothalamus and anterior pituitary as if the reproductive system was in the luteal phase
-ovulation doesn’t occur so no ovum is available to be fertilized

51
Q

Discuss menopause and homeostatic changes that occur.

A

-menopause refers to the cessation of ovarian activity and menstruation
-as the ovaries are depleted of follicles, estradiol and inhibin levels fall and FSH and LH levels are elevated
-primary estrogen source in post-menopausal women is estrone from the adipose tissues
-women with higher fat stores are therefore less prone to osteoporosis
-menopause is accompanied by ‘hot flashes’ as well as atrophy of the urethra, vaginal wall, and vaginal glands

52
Q

Describe fertilization and the acrosome reaction.

A

-fertilization generally occurs in the uterine tubes
-granulosa cells of the corona radiata surround the secondary oocyte produce progesterone that stimulated the influx Ca2+ into the sperm
-sperm contain a large, enzyme-filled vesicle known as the acrosome
-when the sperm comes into contact with the zona pellucida, Ca2+ enters the cell and triggers the acrosome reaction
-reaction involves the fusion of the acrosomal membrane with the plasma membrane of the sperm to allow the release of enzyme to degrade the zona pellucid
-fertilization stimulates the release of Ca2+ from the endoplasmic reticulum of the oocyte, which leads to a Ca2+ wave
-wave activates the fertilized egg, leading to a number of changes including those that block another sperm from fertilizing the egg
-wave also facilitates the continuation of the cell cycle of the egg cell to allow for meiosis II to be completed

53
Q

Define: zygote, morula, blastocyst, and implantation.

A

Zygote: fertilized egg containing a full complement of chromosome (46 in humans)
Morula: very early stage of the embryo that contains 8 cells
Blastocyst: hollow, spherical structure containing 2 cell populations: the inner cell mass that will go on to become and fetus and the surrounding chorion that will become part of the placenta
Implantation: occurs around the 7th-10th day post fertilization; this process involves the burying of the blastocyst into the endometrium; about 75% of lost pregnancies are due to inadequate implantation

54
Q

Discuss where non-pituitary gonadotropins are produced and their role in pregnancies.

A

-to precent menstruation; trophoblast cells of the chorion secretes chroionic gonadotropin (hCG)
-hormone is very similar in structure to LH and is therefore able to maintain the corpus luteum past the time that it would normally regress
-levels of hCG trail off by week 10 of gestation once the placenta is established as a hormone-secreting gland

55
Q

Identify steroid hormones produced by the placenta and indicate their contribution to pregnancy.

A

-Chorionic Gonadotropin (hCG): similar to LH, allows for maintenance of the corpus luteum, may be involved in immune suppression to protect the embryo, also has TSH-like activity
-Chorionic somatomammotropin (hCS): similar to prolactin and growth hormone; promotes fat breakdown and fatty acid release from adipose tissue so glucose can be preferentially transferred to the growing fetus
-Progesteron: helps to maintain the endometrium, suppresses gonadotropin secretion, stimulates the development of alveolar tissue in mammary glands
-Estrogens: helps to maintain the endometrium, suppresses gonadotropin secretion, stimulates mammary development, inhibits prolactin secretion, promotes uterine sensitivity to oxytocin, and stimulate duct development in mammary glands

56
Q

Discuss the role of prolactin during mammogenesis.

A

Mammogenesis is the lobuloaveolar growth within the mammary gland and is induced by prolactin. Prolactin also stimulated milk production within the alveoli.

57
Q

Identify stimuli which result in prolactin secretion.

A

-prolactin is tonically inhibited by dopamine AKA prolactin-inhibiting hormone (PIH)
-dopamine release occurs when estrogen levels are high, such as during pregnancy
-after the placenta is expelled at childbirth, estrogen levels fall and prolactin levels increase
-suckling also stimulates nerves to inhibit release of dopamine from the hypothalamus so milk production continues while breastfeeding
-TRH, GnRH and vasoactive intestinal peptide also positively regulate prolactin

58
Q

Describe the milk let-down reflex.

A

-oxytocin is responsible for the milk let-down reflex
-suckling leads to neuronal signals being sent to the hypothalamus to increase pituitary oxytocin release
-oxytocin then stimulates the contraction of smooth muscle cells surround the lactiferous ducts to allow milk release

59
Q

Discuss breast development during pregnancy and lactation.

A

-during pregnancy, the placenta secretes estrogen and progesterone that facilitates the growth and development of the ducts and glands within the breast
-estrogen inhibits release of prolactin from the anterior pituitary via dopamine (PIH) release from the hypothalamus
-following childbirth, the placenta is lost and estrogen levels fall; allows for prolactin to be released from anterior pituitary to enhance mammogenesis and lactogenesis

60
Q

Discuss the role of oxytocin during labour and lactation.

A

-oxytocin is important for the stimulation of smooth muscle contractions in the uterus that allow labour
-controlling muscle tone of the myometrium following delivery to reduce hemorrhaging, establishing maternal behaviour
-may be involved in the reduction of uterine size following childbirth
-important for milk let-down in lactation

61
Q

Identify stimuli which results in oxytocin release.

A

Suckling on the nipple as well as stretching of the birth canal can stimulate oxytocin release from the posterior pituitary.

62
Q

Identify where oxytocin is produced.

A

Oxytocin is produced in the supraoptic and paraventricular nuclei of the hypothalamus.

63
Q

Discuss the role of prostaglandin F alpha during ovulation and luteolysis.

A

-prostaglandin F2 alpha is involved in the regression of the corpus luteum (luteolysis) in non-pregnant animals
-follicular cells also secrete small amounts of prostaglandins that help with the formation of an ovulatory stigma and follicle rupture

BIOM 3200 (9 decks)

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