A&PII Ch.28 Reproductive System pt.2

Question 1

Female Reproductive System Organs

Answer 1

• Primary is the Ovaries
• Accessory is the fallopian (uterine tubes), uterus, cervix, vagina, external genitalia, and the mammary glands

Question 2

Mammary Gland

Answer 2

• found in the breast
• each located within the anterior thoracic wall
• composed of modified exocrine glands
• secretory product, breast milk
• proteins, fats, lactose sugar for infant nutrition

Question 3

Mammary gland Components

Answer 3

• Nipple which is a cylindrical projection in the center of the breast, has multiple tiny openings of the excretory ducts, transports breast milk
• Areola is the pigmented ring around the nipple and is an uneven surface due to sebaceous glands, areolar glands (glands of Montgomery)
• Suspensory Ligaments which are fibrous connective band supporting the breast, extend from the skin and attach to deep fascia overlying the pectoralis major

Question 4

Alveoli

Answer 4

• secretory units of mammary glands
• produce milk in lactating female
• become more numerous and larger during pregnancy
• drained by lactiferous ducts

Question 5

Pelvic Structures

Answer 5

• Mons pubis: rounded cushion of fatty tissue covered by skin and pubic hair
• Labia Majora: connective tissue, adipose tissue and thickened skin
  -homologous to scrotum in male
• Pudendal Cleft: a furrow separating the paired labia majora
• Labia Minora: highly vascular layer of areolar CT
  -normally covers vaginal orifice, but swells and separates when sexually aroused

Question 6

Vulva

Answer 6

• consists of the labia majora and minora
• the vestibule lies between and is hidden by the paired labia minora
• secretes mucin, mucous lubricant

Question 7

Clitoris

Answer 7

• Partly homologous to the male penis
• Consists of small external glans with deeper internal body
  -consists of a cylindrical shaft containing corpora cavernosa and vestibular bulbs
• Rich in pressure and temperature receptors
• Glans and vestibular bulbs are considered erectile tissue (swells/ engorges)

Question 8

Ovaries (What are they?)

Answer 8

• Portion of Female Reproductive system
• Paired, oval organs containing follicles
  -ovarian follicles are the site of oocyte production and sex hormone release
• Slightly larger than an almond in an adult
  -size varies during each menstrual cycle and during pregnancy

Question 9

Features of the Ovaries

Answer 9

• positioned on either side of the uterus, anchored by the ovarian and suspensory ligaments
• Ovarian arteries, veins, and nerves pass out of the ovary at the hilum
• Outer cortex of the ovary: dense connective tissue interspersed with thousands of ovarian follicles containing developing germ cells
• Inner medulla: areolar connective tissue with arteries, veins, nerves and lymphatic vessels

Question 10

Ovarian Follicles

Answer 10

• consists of an oocyte surrounded by follicle cells
• support the oocyte
• Numerous, found in the cortex
• 6 main types of ovarian follicles representing different stages of development

Question 11

Ovaries Have What Types of Follicles with what descriptions? (1st 3)

Answer 11

1) Primordial Follicles
* most primitive type of ovarian follicles
* primary oocyte and a single flattened layer of follicle cells
-primary oocyte arrested in first meiotic prophase
* 1.5 million present at birth
2) Primary Follicle
* primary oocyte with a single layer of cuboidal follicular cells, now called granulosa cells
* secretes estrogen as it matures
* stimulates changes in the uterine lining
* immediately surrounding the primary oocyte is the zona pellucida
-translucent structure containing glycoproteins
3) Secondary Follicle forms from the primary follicle
* primary oocyte with many layers of granulosa cells
* thecal cells on the periphery of follicle
-help control follicle development
-secrete androgens converted to estrogen by granulosa cells

Question 12

Ovaries Have What Types of Follicles with what descriptions? (2nd 2)

Answer 12

4) Antral Follicle forms from secondary follicle
* Primary oocyte, many layers of granulosa cells, fluid-filled space, antrum
-in the antrum, serous fluid increases as ovulation nears
-oocyte forced to one side of the follicle
- immediately surrounding the oocyte is zona pellucida and corona radiata
-corona radiata is external to zona pellucida; is the innermost layer of cumulus oophorus cells
5) Graafian Follicle (Mature Follicle)
* forms from secondary follicle
* contains a secondary oocyte
-surrounded by zona pellucida and corona radiata
* numerous layers of granulosa cells
* fluid-filled antrum
* completed meiosis I
* arrested in second meiotic metaphase (metaphase II)
* one formed per month

Question 13

Corpus Types (continuation of follicle types)

Answer 13

5.5) Corpus hemorrhagicum
* a temporary structure that forms immediately after ovulation
-follicle fills with blood and clots
6) Corpus Luteum
* forms from remnants of follicle
-after mature follicle ruptures and oocyte is expelled
* persists and secretes hormones if pregnancy occurs
-stimulate buildup of uterine lining
-prepare uterus for possible implantation of fertilized oocyte
7) Corpus Albicans
* formed from regressed corpus luteum
* white connective tissue scar
* most structures completely reabsorbed

Question 14

Folliculogenesis and Ovarian Cycle

Answer 14

• occurs puberty to menopause
• Folliculogenesis (follicle development) begins at puberty
  -regulated by hypothalamus releasing GnRH, which stimulates release of FSH and LH
  -produces monthly sequence of events, known as the ovarian cycle
• 3 phases: follicular phase, ovulation, and luteal phase

Question 15

Follicular Phase

Answer 15

• typically shown as days 1-13 of 28-day ovarian cycle
• around 20 primordial follicles stimulated to mature into primary follicles by LH and FSH
  -unclear why some are stimulated and some not
• granulosa cells release inhibin
  -helps inhibit further FSH production
  -prevents excessive follicle development
  -usually only one matures to Graafian follicle
• Volume of fluid increases within follicle antrum
  -oocyte forced to one side of follicle

Question 16

Oogenesis and the Ovarian Cycle

Answer 16

• During the follicular phase, arrested primary oocytes resume growth, finish meiosis I and divide into 2 daughter cells
  -In antral follicle
• One, polar body
  -Nonfunctional, receives minimal cytoplasm and regresses
• Other cell derived from primary oocyte
  -receiving bulk of cytoplasm
  -becomes secondary oocyte
  -reaches metaphaseII before arrested again
  -completes meiosis if fertilized
  -if not, breaks down in 24 hours

Question 17

Ovulation

Answer 17

• release of secondary oocyte from mature follicle
• occurs on day 14 of 28-day cycle
• usually only one ovary ovulates each month
• induced with peak in LH secretion
• antrum increases in size and swelling
  -expands until ovarian surface thins
  -eventually ruptures, expelling secondary oocyte

Question 18

Luteal Phase

Answer 18

• remaining follicle cells become corpus luteum
• occurs on days 15-28 of cycle
• Corpus luteum
  -temporary endocrine gland
  -secretes progesterone and estrogen
  -builds up uterine lining, prepares for fertilized oocyte
  -lifespan is 10-13 days if oocyte is not fertilized

Question 19

Luteal Phase Continued

Answer 19

• Corpus luteum regression
  -causes drop in secreted progesterone and estrogen
  -causes shedding of uterine lining, menstruation
  -sheds lining, menses
  -marks end of luteal phase

Question 20

If secondary oocyte is fertilized and implants

Answer 20

• called a pre-embryo
• starts secreting human chorionic gonadotropin hCG
• mimics effects of LH and continues to stimulate corpus luteum
• corpus luteum continues to produce estrogen and progesterone
• maintains and builds uterine lining
• placenta produces its own progesterone and estrogen after 3 months
• corpus luteum has regressed into corpus albicans

Question 21

Fallopian Tubes

Answer 21

• AKA uterine ducts
• extend laterally from uterus; divided into 4 distinct regions
  1) Infundibulum: has fimbriae that sweep oocytes into the ostium
  2) Ampulla: site of fertilization
  3) Isthmus: accounts for 1/3 of length
  4) Intramural segment: where isthmus enters the uterine cavity

Question 22

Layers of the Fallopian Tube

Answer 22

• Outermost layer: thin, protective serosa
• Middle layer: two smooth muscle layers; contractions serve to transport the oocyte/ blastocyte to the uterus
• Inner layer: highly-folded mucosa lined with ciliated epithelium
  -epithelial cells produce tubular fluid that promotes gamete/zygote survival

Question 23

The Uterus

Answer 23

• structurally divided into 4 regions
  1) Fundus (base of inverted pair shape)
  2) Body (broad region)
  3) Isthmus (narrow region)
  4) Cervix (projects into vagina)
• Function: structure of gestation (receives, retains and nourishes fetus)
• Anchored in place by several ligaments

Question 24

The Layers of the Uterus

Answer 24

• Perimetrium: outer serosa
• Myometrium: 3 layers of smooth muscle
• Endometrium: site of implantation
  -Basal layer: permanent structure; contains arteries and acini from uterine glands
• Functional Layer: hormone-responsive layer; grows in the presence of hormones and degenerates/ sheds during menses

Question 25

Uterine Cycle

Answer 25

* cyclical changes in endometrial lining * influenced by estrogen and progesterone * 3 distinct phases of development -menstrual phase, proliferative phase, secretory phase * Timeline based on 28-day uterine cycle -Varies, 21 to 35 day cycle

Question 26

Uterine Cycle phases

Answer 26

1) Menstrual Phase: characterized by menses * days 1-5 of cycle * sloughing off of the functional layer * lasts through a period of menstrual bleeding 2) Proliferative Phase: dominant follicle rapidly growing; estrogen-priming for endometrial repair, regeneration * days 6-14 of cycle * development of new functional layer of endometrium * overlaps time of follicle growth and ovary estrogen secretion 3) Secretory Phase: endometrium becomes vascularized in preparation for pregnancy *days 15-28 of cycle *increased progesterone secretion from corpus luteum *results in increased vascularization and uterine gland development *w/out fertilization -degeneration of corpus luteum -dramatic drop of progesterone -without progesterone, sloughs off functional layer

Question 27

Cervix

Answer 27

* Dome-like structure of uterus that projects into vagina * The endometrium is NOT shed during menses, and myometrium is much thinner * Cervical canal joins uterus to vagina * Mucosa produce secretions that create a mucous plug for pregnancy

Question 28

Vagina

Answer 28

* Functions: copulatory organ, passageway for outflow of menstruation, and birth canal during parturition * Consists of three layers: outer adventitia middle muscularis and inner mucosa * Natural home to several non-pathogenic microorganisms, due to warm and moist environment * Acidic secretions prevent infection from foreign microbes

Question 29

Histology of the Vagina

Answer 29

* Mucosa contains the epithelium of non-keratinized stratified squamous epithelium and the Lamina propria * It also contains the Muscularis Layer

Question 30

What is the Climacteric and Female v.s. Male?

Answer 30

* The termination of the reproductive years :( Females its called Menopause * Males have decreased testosterone production which leads to loss in testicular volume and sperm production * Males experience diminished sex drive, occasional mood swings, erectile dysfunction/impotence, and prostate enlargement * Females have a drop in circulating estrogen, ovaries are devoid of follicles and menstruation stops, reproductive organs undergo modest atrophy; vagina lubrication is reduced, breast tissue atrophies * Females may experience hot flashes (hypothalamus controlled by estrogen), figure becomes more androgynous; bones become brittle

Question 31

Menopause and Perimenopause

Answer 31

* Perimenopause= time near menopause, irregular or skipped periods without pregnancy * Menopause is when women cease cycling for a year and are not pregnant and dont have any other medical conditions * Normal onset is ages 45 to 55 * No more ovarian follicles remain or follicular maturation stops * Significant amounts of progesterone, estrogen no longer secreted * Uterine lining no longer growing -no further menstrual periods

Question 32

Menopause again

Answer 32

* "Hot flashes" with periodic elevation in body temperature * Thinning scalp hair and increased facial hair * Increased risk of osteoporosis and heart disease

Question 33

Tubal Pregnancy

Answer 33

* A.k.a Ectopic Pregnancy * Fertilized oocyte implants outside of the endometrium * Tubal Pregnancy is a type of Ectopic pregnancy - fertilized egg implants in the uterine tube -unable to expand as embryo grows -embryo viable only until week 8 -uterine wall ruptures if embryo is not removed -hemorrhage and loss of mother's life is possible

Question 34

Endometriosis

Answer 34

* Parts of the endometrium are displaced * Tissue becomes implanted on external surface of organs within the abdominopelvic cavity * May grow under influence of hormones * Cannot be expelled normally * May cause pain and scarring * Often linked to fertility problems * Treatment includes hormones to slow the growth of endometrial tissue or surgery

Question 35

Cervical Cancer

Answer 35

* Common Malignancy of the female reproductive system * Its most important risk factor is Human papillomavirus (HPV) infection -vaccine available for 4 most common types *Pap Smear is used to detect cervical cancer in early stage -epithelial cells scraped from cervix edge -examined for abnormal development