Please enable JavaScript.
Coggle requires JavaScript to display documents.
REPRODUCTIVE SYSTEM AND DEVELOPMENT (Fetal Development (Weeks 9-12…
REPRODUCTIVE SYSTEM AND DEVELOPMENT
Male Reproductive Structures
Primary Reproductive Organs
Testes
Scrotum
Homologous to labia majora
Houses testes
Spermatic cord
Blood vessel and nerve supply
Produce sperm
In seminiferous tubules
Produce androgens
Testosterone
Epididymis
Stores sperm until matured
From epididymis
to vas deferens
to ampulla
to seminal vesicle
1 more item...
Secondary Reproductive Organs
Penis
Organ for copulation
Passageway for urine and semen
Corpus Cavernosum
Corpus spongiosum
Homologous to female clitoris
Complex set of ducts and tubes
Accessory glands and semen production
seminal vesicles
secretes a viscous, whitish-yellow, alkaline fluid
contains prostaglandins and fructose
facilitates sperm entry into the uterus
prostate gland
produce mucin
secretes a milky fluid slightly acidic and rich in citric acid, seminalplasmin, and prostate-specific antigen (PSA)
Sperm and urinary tract health
serves to neutralize the acidity of the vagina
bulbourethral glands (Cowper glands)
secretes a clear, viscous mucin that forms mucus
Coats and lubricates the urethra for passage of sperm
semen
Seminal fluid from the accessory glands combined with sperm
Female Reproductive Structures
Primary Reproductive Organs
Ovaries
Paired within the pelvic cavity
Supplied by ovarian artery and ovarian vein
Contains ovarian follicles
Which contains oocyte
Accessory reproductive organs
Uterine tubes
Transports oocyte to uterus
Site of fertilization
Uterus
Pear-shaped
Muscle
Site for implantation of embryo
Vagina
Copulatory organ
Passageway for menstruation
Birth canal
External genitalia
Mons pubis
Labia majora
Homologous to scrotum
Labia minora
Vestibule
Urethral opening and vaginal opening
Clitoris
Erectile tissue
called
Corpora cavernosa
Prepuce
Fold that covers clitoris
Homologous to penis
Mammary glands
Secretory
Breast milk
provides nutrients for baby
Meiosis
Oogenesis
Meiosis I Begins in fetal development and pauses until puberty
Oogonia
Diploid cells (containing 46 chromosomes)
Oogonia divide by mitosis and differentiate to produce primary oocytes
Remains at prophase I until puberty
When puberty begins
Approximately 20 primordial follicles mature into the primary follicles every month
2 more items...
Spermatogenesis
Begins at puberty
Occurs within the seminiferous tubule
Spermatogonia
Germ cells that are the origin of sperm are diploid cells (containing 46 chromasomes)
Mitotic divisions of these cells produce a new germ cell and a committed cell
Committed cell is a primary spermatocyte
Meiosis I begins in the diploid primary spermatocytes. The haploid cells (23 chromasomes) produced during meiosis I are called secondary spermatocytes
1 more item...
Hormones of the Reproductive System
Male Hormones
Hypothalamus begins secreting GnRH at puberty
GnRH stimulates anterior pituitary
to secrete FSH and LH
LH stimulates the testes to produce testosterone and androgens
Testosterone stimulates final stages of sperm development in seminiferous tubules
Female Hormones
Hypothalamus
Stimulates GnRH
That stimulates the anterior pituitary
To secrete
Follicle Stimulating Hormone
Stimulates the development of the follicle from primary through mature stages
Leutenizing Hormone
Stimulates mature follicle to secrete estrogen and progesterone
stimulates meiosis in primary oocyte
Menstrual Cycle
Hypothalamus initiates the ovarian cycle by secreting GnRH which stimulates the anterior pituitary to secrete FSH and LH
FSH & LH target the ovaries and stimulate follicular development
This causes maturation of follicles
Maturing ovarian follicle secrete inhibin and estrogen
Inhibin helps inhibit FSH release by the anterior pituitary, low levels of estrogen inhibit production of GnRH, FSH, and LH
Positive feedback loop results in an LH surge from the anterior pituitary which induces ovulation
Corpus luteum forms from the ovulated follicle
Corpus luteum secretes large amounts of progesterone, estrogen, and inhibin
1 more item...
Degenerates in 10-13 days if not fertilized
1 more item...
Estrogen assists with development of the mature ovarian follicle
Mature follicle produces a larger threshold amount of estrogen
Embryonic Development
Pre-embryonic period
Fertilization
Sperm penetrates secondary oocyte; secondary oocyte completes meiosis II and becomes an ovum; ovum and sperm plasma membranes fuse
Zygote
Diploid cell produced when ovum and sperm pronuclei fuse
Cleavage
Zygote undergoes cell division by mitosis to increase cell number, but overall size of structure remains constant
Morula
2 more items...
In the uterine tube 30 hours to day 3 post-fertilization
Ampulla of uterine tube at the end of fertilization
Ampulla of uterine tube within 12-24 hours after ovulation
First 2 weeks of development
Embryonic period
3 - 8 weeks of development
Now called an embryo
Fetal period
Remaining 30 weeks of development prior to birth
Fetal Development
Weeks 9-12
Primary ossification centers appear in most bones
Reproductive organs begin to develop
Coordination between nerves and muscles for movement of limbs occurs
Brain elongates and enlarges
Epidermis and dermis of the skin become more fully developed
Permanent kidneys develop
Palate develops
9 centimeters and 28 grams
Weeks 13-16
Body grows rapidly
Ossification in the skeleton continues
Limbs become more proportionate in length to body
Brain and skull continue to enlarge
14 centemeters and 170 grams
Weeks 17-20
Muscle movements become stronger and more frequent
Lanugo covers skin
Limbs near final proportions
Brain and skull continue to enlarge
19 centemeters, 454 grams
Weeks 21-38
Body gains major amount of weight
Subcutaneous fat is deposited
Eyebrows and eyelashes appear, eyes open
Testes descend to scrotum if a boy
Blood cells form in marrow only
38 weeks - 36 centemeters, average weight 2.5-4.5 kilograms