Week 3: The Reproductive System

What are the breasts composed of?

\-Glandular, fibrous, and adipose tissue

\-Alveoli, lactiferous ducts and sinuses

What happens to the nipples during pregnancy?

They become more erect and get darker

Why are Montgomery’s Tubercles important for breastfeeding?

\-Secrete a substance to keep the nipple moist

\-Create smell that attracts the baby

What does the pelvic floor do?

It acts as a support system that overcomes the force of gravity?

Pelvic diaphragm

Deep fascia, levant ani, and coccygeal muscles

What happens to the pelvic diaphragm during birth?

It dilates

Does the pelvic floor return to pre-pregnant condition after birth?

Yes

What are the functions of the vagina?

\-Passageway fro sperm/fetus

\-Passageway fro menstrual blood flow

\-Protection against trauma from sexual intercourse and infection of uterus, ovaries, and pelvis

What is the significance of the vaginal vault and rugae of the vagina?

Allow for stretching during labor

What is the pH of the vagina during reproductive years?

4-5

\-Acidic

What are the 2 main sections of the uterus?

\-Corpus

\-Cervix

What comprises 2/3s of the uterus?

Corpus

What are the 3 layers of the corpus (uterus)?

\-Serosal layer

\-Muscular layer

\-Mucosal layer

Serosal Layer of the Uterus

Perimetrium

Muscular Layer of the Uterus

Myometrium

Mucosal Layer of the Uterus

Endometrium

Function of the Uterus

\-Lubrication

\-Bacteriostatic agent

\-Provides alkaline environment

What is the weight and length of the uterus?

40-70 grams and 6-8 cm

How does the appearance of the cervix change after pregnancy?

It changes from a dimple appearance to a slit appearance

What is the purpose of the round and broad ligament?

Hold everything in place and stretch during pregnancy

What are the three sections of the fallopian tubes?

\-Ampulla

\-Isthmus

\-Fimbria

What section of the fallopian tubes is the biggest?

Ampulla

\-2/3 of fallopian tube

What portion of the fallopian tube is 1/3 of the tube and where tubes would be ties?

Isthmus

What are the functions of the fallopian tubes?

\-Transport for ovum from ovary to uterus

\-Safe site fertilization

\-Warm, moist, nourishing environment fro ovum or zygote

What part of the fallopian tube is where fertilization normally occurs?

Ampulla

What do the ovaries produce?

\-Female ovum

\-Estrogen and progesterone

What is the corpus luteum?

A glandular body that forms from the remnants of the Graafian follicle after ovulation

What is the source of progesterone and estrogen during the 2nd half of the ovulatory cycle?

Corpus luteum

What hormone does the hypothalamus release?

Gonadotropin-releasing hormone (GnRH)

In response to the release of GnRH, what does the anterior pituitary gland secrete?

\-Follicle-stimulating hormone

\-Luteinizing hormone

Function of FSH

\-Maturation of ovarian follicles

\-the eggs within each follicle gradually develop and get ready to be ovulated

Function of LH

Needed for final maturation of follicle

What serves as the final trigger to ovulation?

LH surge: a dramatic increase in LH production

What hormone is associated with femaleness characteristics?

Estrogen

\-includes breast alveolar lobule growth and duct development

What hormone is responsible for developing fertile-quality cervical fluid as ovulation approaches?

Estrogen

What is the “hormone of pregnancy”?

Progesterone

What is the heat producing hormone?

Progesterone

What hormone is responsible for maintaining endometrium after ovulation?

Progesterone

How many days after ovulation does menstruation occur?

14 days

What initiates the start of the menstrual cycle?

The sudden drop in progesterone

What days do the menstrual phase occur?

Days 1-6

What causes the uterine lining to wash away?

Blood vessels begin to constrict

What hormone levels are high during the menstruation phase? Low?

High: FSH

Low: Estrogen and progesterone

What is the cervical mucous like during the menstrual phase?

Scanty, viscous, and opaque

\-not feral quality

What days of the menstrual cycle is the proliferative phase?

Days 7-14

What is the cervical mucous like during the proliferative phase?

Thin, clear, watery and alkaline

\-favorable to sperm

\-Spinnbarkheit

What happens to the blood vessels and the endometrium during the proliferative phase?

The blood vessels dilate and the endometrium thickens

What happens to the body temperature at ovulation?

Drop then rises sharply

What causes the body temperature to drop then sharply rise at ovulation?

Progesterone

What happens to the follicle on day 14?

It swells causing the follicular wall to weaken

When does ovulation occur, specifically with the follicle?

When the follicle rupture and the ovum is propelled through the ovarian wall ovulation

At what position is the cervical the most fertile?

Soft, high, and open

\-On day 14

What is mittelschmerz?

Ovulatory pain that lasts anywhere from minutes to hours and felt on the side where ovulation occurs

What days do the secretary phase take place in the menstrual cycle?

Days 15-26

What happens to the estrogen levels during the secretory phase?

Levels fall

What phase follows ovulation?

Secretary phase

What happens to the cervix and cervical fluid on day 16 of the uterine phase?

The cervix returns to firm, low, and closed position and cervical fluid has disappeared

When does the ischemic phase of the menstrual cycle occur?

If fertilization does not occur

What happens to the corpus luteum, estrogen, and progesterone in the ischemic phase?

Levels fall and corpus luteum degenerates

What are the 2 phases of the ovarian cycle?

Follicular and luteal phase

What days of the ovarian cycle does the follicular phase take place?

Days 1-14

What days of the ovarian cycle does the luteal phase take place?

Days 15-28

When does the luteal phase occur?

When ovum leaves follicle

In the luteal phase, what happens if fertilization occurs?

Ovum implants in endometrium and secretes hCG

In the luteal phase, what happens if fertilization does not occur?

The ovum degenerates and stops producing estrogen and progesterone

If a person is experiencing extreme stress, what phase of the ovarian cycle would this impact?

It can increase the length of the follicular phase or the beginning on the cycle

How does the birth control pill affect the menstrual cycle?

Progesterone works by decreasing GnRH which reduces the production of FSH and LH

Estrogen serves to stabilize the endometrium and prevent irregular bleeding

Meiosis Definition

Cell division by which diploid cells give rise to gametes =

Is meiosis a one stage or two stage cell reproduction?

Two stage

Are gametes haploid or diploid?

Haploid, so not identical

Meiosis 1st Division

\-Chromosomes replicate, pair, and exchange information

\-Chromosome pairs separates and cell divides

Meiosis Second Division

\-Chromatids separate and move to opposite poles

\-Cells divide, forming four daughters cells

\-Haploid cells

Female Gametogenesis

\-M1 begins in female fetus

\-Arrested

\-1st division occurs at ovulation

\-2nd division occurs at fertilization

What is the result of female gametogenesis?

One haploid and 3 polar bodies

Zona pellucida

Clear, noncellular layer whose thickness influences fertilization rate

Corona radiata

Ring of elongated cells that radiate from the ovum and are held together by hyaluronic acid

How long can sperm survive in the female reproductive system?

48 to 72 hours

\-mostly healthy and fertile for first 24 hours

Capacitation

\-Removal of protective coating from heads of sperm

\-Small perforations form in the acrosome

Acrosomal reaction

Allows for escape of enzymes which are needed for the sperm to penetrate the ovum

What is considered the pre-embryonic stage?

First 14 days of human development

What is cleavage pertaining to pre-embryonic stage?

Rapid mitotic division form a solid ball of cells

What is the blastocyst?

Inner solid mass of cells (Embryo and amnion)

What is the trophoblast?

Outer layer of cells (Chorion of placenta)

Amniotic Fluid Function

\-Acts as cushion against mechanical injury

\-Helps control temperature

\-Permits symmetrical external growth

\-Allows umbilical cord to be relatively free of compression

\-Acts as wedge during labor

\-Provides fluid for analysis

What kind of pH is the amniotic fluid?

Slightly alkaline

Normal Amniotic Fluid Amounts

10 weeks: 30 mL

20 weeks: 350mL

>20 weeks: 700-1000mL

Oligohydramnios

Less than 400 mL

Hydraminos (Polyhydraminos)

Greater than 2000mL

What are the 3 vessels of the umbilical cord?

2 arteries and 1 vein

Fetal Circulation

Oxygenated blood → Umbilical cord → Abdominal wall

Ductus venous → IVC

R Atrium

Foramen Ovale → L Atrium

L Ventricle → Aorta

R Ventricle → Lungs via pulmonary artery

Ductus arteriosus → Descending aorta

Returns to placental through arteries (umbilical)

Embryonic Development Time Frame

Day 15 - Week 8

When is the embryo most vulnerable to teratogens?

During the embryonic phase

Week 4 Development

\-Development of GI tract

\-Vertebrae bing

\-Heart develops (beating and circulation)

\-Eyes, nose, arm, legs form

Week 6 Development

\-Trachea

\-Liver produces blood cells

\-Digits

\-Tails recedes

Week 8 Development

\-Resembles human

\-Face

\-Auricle of ears

\-Unidentifiable but visible genitalia

\-GU and GI developed

\-Well developed circulation through umbilical cord

\-Long bones form

Week 9 Development

\-Every organ system is present

\-Refining and perfecting

Week 12 Development

\-Genitals well-differentiated

\-Fetal heart tones can be heard

\-Urine produced

Week 16 Development

\-Amniocentesis can be done

\-Lanugo develops

\-Clearly developed blood vessels

\-Sucking motions

\-Swallows amniotic fluid

\-Produces meconium

Week 20 Development

\-Quickening has occurred

\-Lanugo covers body

\-Less transparent skin

\-Nipples, eyebrows and eyelashes appear

Week 24 Development

\-Micro preemie

\-Age of viability

\-Hair, eyelashes, and eyebrows formed

\-Red and wrinkled skin

\-Covered in vernix