Ib 140 Human Repro

Front 1

Biological Activity of Steroid Horomones in Tissue Depends on

Back 1

Local Concentration of Hormone

# of Receptors for Hormones present

Upregulation and Downregulation of Receptors

Timing of Some Reproductive Function

Front 2

Phytoestrogens

Back 2

from soy, have weak estrogenic effects

Front 3

Xenoestrogens

Back 3

human made chemicals (DDT, water bottle plastics) very strong estrogenic effects

Front 4

Synthetic Analogs

Back 4

Molecules made by chemists similar to estrogen

Front 5

Name the three Endogenous Estrogen going from strongest to weakest

Back 5

Estradiol
Estriol
Estrone

Front 6

Oxytocin

Back 6

peptide hormone secreted from Neurohypophysis

stimulates contractile cells of mammary glands to eject milk

causes smooth muscle in uterus to contract

Front 7

Vasopressin

Back 7

peptide hormone secreted from Neurohypophysis

cause kidney to retain water (anti-diarretic)

causes blood pressure to constrict and blood pressure to rise

Front 8

ACTH (adreno-corticotropin horomone)

Back 8

peptide hormone released from adenohypophysis

stimulate adrenal glands to secrete steroid horomone

Front 9

TSH (thyrotropin)

Back 9

peptide hormone released from adenohypophysis

stimulates thyroid horomone

Front 10

PRL (prolactin)

Back 10

peptide horomone released from adenohypophysis

supports mammary glands in females to produce milk

Front 11

MSH (melanophore stimulating horomone)

Back 11

peptide horomone released from adenohypophysis

stimulates production of melenin

Front 12

LPH (lipotropin)

Back 12

peptide hormone secreted from Adenohypophysis

Breaks down fat

Front 13

Ophiods

Back 13

peptide horomone released from adenohypophysis

natural pain killers

endorphins and enkephalins

Front 14

FSH

Back 14

peptide horomone released from adenohypophysis

Stimulates gonads to produce germ cells

Stimulates Follicular Cells to produce estrogen

Front 15

LH

Back 15

peptide horomone released from adenohypophysis

Stimulates gonads to secrete sex horomones, testes to secrete androgens

Induces egg release

Front 16

Hypophysiotropic Area (HTA)

Back 16

can increase or decrease the synthesis and secretion of adenohypophysis hormones

Front 17

RH (releasing horomone)

Back 17

hormone secreted from hypothalamus that increases output of specific adenohypophysial horomone

Front 18

RIH (releasing-inhibiting hormone)

Back 18

hormone secreted from hypothalamus that decreases output of specific adenohypophysial horomone

Front 19

gonadostat

Back 19

Hypothalamus control center

monitors level of estrogen and progesterone

Front 20

Name the three Gonad Glycoprotein Hormones and which inhibits what?

Back 20

Inhibin directly inhibits the pituitary glands to suppress the secretion of FSH

Activin inhibits inhibin

Follistatin inhibits activin

Front 21

Estrogen Effects

Back 21

Upregulates estrogen, LH, and progesterone receptors

Supports proliferation and development of ovarian granulosa cells

Supports maturation and maintainance of fallopian tubes, uterus, cervix and vagina

Supports development of 2ndary sex characteristics

Stimulates prolactin secretion

Front 22

Progesterone Effects

Back 22

Supports secretory activity of uterus during luteal phase

Raises the uterine threshold to contractile stimuli during pregnancy

Front 23

Name the two endogenous Androgens

Back 23

Testosterone

DHT

Front 24

Androgen Effects

Back 24

Causes prenatal differentiation of wolffian ducts

development of secondary sex characteristics at puberty

maintains spermatogenesis in Sertoli cells

Increases libido

Front 25

External Genitalia

Back 25

vulva (mons pubis, labia majora, labia minoa, vaginal introitus, hymen, clitoris)

Front 26

Secondary sex characteristics

Back 26

enlarged breasts

fat in torso

Front 27

Ovarian stroma

Back 27

connective tissue framework divided into the outer ovarian cortex and the inner ovarian medulla

Front 28

membrane granulosa

Back 28

follicular cells surrounding oocyte

Front 29

zona pellucida

Back 29

transparent membrane between oocyte and follicular wall

Front 30

thecal cells (theca)

Back 30

in ovary surrounding the follicular cells

have LH receptors that facilitate development

Front 31

Types of ovarian follicles

Back 31

Primordial
Primary
Secondary
Tertiary - Graafian Follicle

Front 32

Ovarian Follicles through life

Birth
Puberty
35 years old
Menopause

Back 32

Birth - 1-2 million
Puberty - 200,000
35 years old - 100,000
Menopause - 0

one oocyte ovulates a month

Front 33

∆5 pathway

Back 33

Tertiary Follicle Growth and Horomone Secretion

FSH supported rapid growth of tertiary follicles

stimulates estrogen production in granulosa cells of tertiary follicles from cholesterol (precursor for steroid hormones)

Front 34

∆4 pathway

Back 34

Graafian Follicle Growth and Secretion

LH supported growth and secretion (receptors change)

"lutenization"

stimulates progesterone production first

Front 35

How many tertiary follicles from each of the two ovaries are formed each month?

Back 35

Each ovary forms 20 tertiary follicle, 40 total

Only one of these follicles matures to Graffian stage

Alternates left and right

Front 36

Oogenesis

Back 36

production of mature haploid (1N) female gamete

Front 37

When is the first meiotic division is complete?

Back 37

When the membrane of the oocyte nucleus disintergrates

Front 38

Stigma

Back 38

Area of follicular wall that ruptures open to allow ovum (secondary oocyte) to move outside of ovary into the oviduct

Front 39

Diploid Primary Oocyte

Back 39

Diploid primary oocyte contained in most ovarian follicles is arrested in first meiotic division

Surge in LH in middle of menstrual cycle causes completion of the first division, producing a secondary oocyte (ovum) and a first polar body

Front 40

Secondary Haploid Oocyte

Back 40

Begins meiosis II while still in follicle but does not complete until after ovulation

Front 41

Ovulation

Back 41

caused by LH and involves degredation of follicle wall

A tear in the follicular wall at stigma allows ovum to ooze out with follicular fluid

Front 42

Oocyte maturation and ovulation: second meiotic division completion

Back 42

after ovulation, ovum moves into oviduct for second meiotic arrest

When sperm penetrates, the ovum meiotic division is completed to produce a mature haploid (1n) ootid + polar body

minutes later it is a zygote

Front 43

Corpus Luteum

Back 43

formed from collapsed follical form, (ovulated follicle)

Lutenized granulosa cells (luteal cells)

present during last two weeks of menstration

Front 44

Infundibulum

Back 44

enlarged oviductal region at the ovarian end that recieves the ovulated egg from the ovarian follicle

Front 45

Fimbriae

Back 45

fingerlike projections at the ends of infundibulum

Front 46

Oviductal isthmus

Back 46

embedded in uterine wall

Front 47

oviduct

Back 47

fallopian tubes

internal lining of the oviduct has mucus and ciliated cells, and smooth muscles
that beat in the direction of the uterus

Front 48

Estrogens effect on oviduct

Back 48

increase musous secretion

causes cilia to beat faster, smooth muscle to contract more

seek to transport ovum

Front 49

Progesterone effects on oviduct

Back 49

decrease mucous secretion

decrease smooth muscle contraction

Front 50

Fundus

Back 50

dome shape area of womb (uterus) above the entrance of oviducts

area opposite from opening

Front 51

Corpus

Back 51

"body" of uterus that tapers down to cervix

Front 52

Cervix

Back 52

narrow region near vagina

Front 53

Uterine Endometrium is composed of...

what do they do?

Back 53

Stratum Functionalis - internal surface layer that is shed during menstration

Stratum basalis - deeper layer is not shed during menstruation and contains blood vessels

Front 54

Cervical Canal

Back 54

connects vagina with uterine cavity, passageway for sperm as well as menstral blood

Front 55

Internal cervical os

Back 55

opening of cervical canal into uterine cavity

Front 56

External cervical os

Back 56

opening of cervical canal into vaginal cavity

Front 57

Vaginal position

Back 57

lies between urinary bladder and rectum

Front 58

Tunica mucosa

Back 58

inner layer of vagina,rich in elastic fibers, stretches

Front 59

Tunica musularis

Back 59

middle layer of vagina rich in smooth muscle

Front 60

Tunica adventitia

Back 60

thin outer layer of elastic tissue of vagina

Front 61

Sphincter of skeletal muscles at the vaginal opening is under what control?

Back 61

voluntary control

Front 62

Vagina acidic environment inhibits what?

Back 62

yeast (fungal) growth

Front 63

Mons pubis

Back 63

cushion of fatty tissue covered by skin and pubic hair of vagina

Front 64

Labia majora

Back 64

major lips of vagina, fleshy folds, homologues to male scrotum

Front 65

Vulva

Back 65

External Female Genitalia

Front 66

Labia minora

Back 66

smooth tissue underlying labia majora of vagina

tissue contains oil glands

opens up during sexual stimulation

Front 67

Vestibule

Back 67

cavity between labia minora of vagina

most of this is made of vaginal introitus

contains Hymen

Front 68

Hymen

Back 68

membrane of connective tissue that partially covers the introitus in virgins

Front 69

Urethral Orifice

Back 69

anterior to the vaginal introitus

Front 70

Lesser Vistibular Glands (Skene's glands)

Back 70

Positioned below or to either side of urethral orifice

homologous to male prostate gland

secretes fluid

Front 71

Greater vestibular gland (Bartholin's glands)

Back 71

positioned on each side of introitus

secretes mucus

homologous to bulbourethral glands in males

Front 72

Clitoris

Back 72

Located in Anterior Junction of two labia minora, above urethral orifice

Partially homologous to penis

Front 73

Clitoral Shaft

Back 73

Like shaft of male penis

contains spongy cylinders (corpora cavernosa)

fills up with blood and becomes erect

Front 74

Clitoral Glands

Back 74

covered by the clitoral prepuce

homologous to glans penis

Front 75

Mammary Glands

Back 75

Consists of glandular tissue and associated ducts embedded in fatty tissue

Serves as stimulus for sexual arousal

Growth and function of glandular tissue are controlled by hormones

15-20 lobes separated by fat and ligamentous tissue

Front 76

Mammary alveolus

Back 76

functional unit of mammary gland made up of a hollow sphere where milk is secreted

Front 77

Mammary Gland Hormonal Control
by age

Back 77

E and P controls growth and development of mammary glands

prepubertal females - mammary gland tissue is relatively inactive

puberty - ovaries begin to secrete estrogen and alveoli and ducts begin extensive growth

menstrual cycle- breast glandular tissue enlarges

pregnancy - causes glandular tissue to enlarge and ducts to branch

Front 78

What induces prolactin secretion?

Back 78

suckling of nipple

Front 79

Breast Cancer

Back 79

Genetics

Influenced by lifetime exposure of natural and environmental estrogens

Front 80

Estrous Behavior

Back 80

In mammals when females are only sexually responsive to males only around the time of ovulation when estrogen levels are high

Front 81

Monestrus

Back 81

One time of estrous a year

Front 82

Induced ovulation

Back 82

females are continually receptive to males and only ovulate as result of stimulus from coitus

Front 83

Light Effects

Back 83

Light causing continuous estrous

Front 84

Spontaneous ovulators

Back 84

Human female estrous behavior

Ovulation occurs periodically whether or not coitus occurs

Front 85

Mittelschmerz

Back 85

pain during the time of ovulation

Front 86

Cervical mucus

Back 86

form of ovulation detection

becomes more abundant, watery stringy

Front 87

Spinnbarheit

Back 87

form of ovulation detection

threadability of mucus

Front 88

Fern Test

Back 88

form of ovulation detection

fern-like pattern of crystals of sodium and potassium chloride when dried

Front 89

Pregnanediol

Back 89

form of ovulation detection

breakdown product of progesterone

detected in the urine during luteal phase

Front 90

How to Oral Contraceptives Work?

Back 90

Mimics progesterone and estrogen levels at luteal phase

are high and low respectively

thus, FSH and LH is inhibited,
prevents follicular development, estrogen production, and ovulation

Front 91

When does the Corpus Luteum degenerate?

Back 91

4 days before menstruation

Front 92

When does PMS begin

Back 92

3-10 days before menstruation

Front 93

Amenorrhea

Back 93

Absence of Menstruation

Front 94

Primary Amenorrhea

Back 94

a female who has not menstruated by 16

caused by low body fat, extreme exercise

Front 95

Secondary Amenorrhea

Back 95

When menstruation has not occurred in an adult women for at least 6 months

caused by low body fat, extreme exercise, pregnancy, lactation, menopause

Front 96

Oligomenorrhea

Back 96

When an adult woman skips one or few cycles

caused by stress, intense exercise, poor nutrition, anorexia, illness, ovary disease

Front 97

Male sex accessory ducts

Back 97

receive, store, and transport sperm

Front 98

Sex accessory glands

Back 98

add substances to ducts

Front 99

spermatic cord

Back 99

method by which testes is suspended from body wall

Front 100

inguinal canal

Back 100

route which testes originally descended into the scrotum from the pelvic cavity before birth

Front 101

Vas deferens

Back 101

one of the accessory ducts in spermatic cord

Front 102

Tunica vaginalis

Back 102

shiny covering on outside of each testes

Front 103

Tunica albuginea

Back 103

dense covering of the testes

Front 104

Testicular lobules

Back 104

inside testes

compartments separated from each other by septa

Front 105

Seminiferous epithelium

Back 105

lines the inside of the each seminiferous tubule and contains two types of cells (male germ cell and Sertoli cell)

Front 106

Male germ cell

Back 106

life in the inner wall of each seminiferous tubule and produce sperm

Front 107

Sertoli cells

Back 107

Nurse cells

nurture and provide structural support for sperm cells during development

Front 108

Spermatogenesis

Back 108

process by which a diploid spermatogomium transforms into 4 haploid spermatids

Front 109

Spermiogenesis

Back 109

process by which 4 haploid spermatids transforms into 4 haploid spermatozoa (sperm cells)

Front 110

Spermatogonia

Back 110

immature germ cells that are diploid (2n),

have 46 chromosomes

lying next to wall of each seminiferous tubule

can undergo meiotic division

Front 111

Spermiation

Back 111

sperm heads are released from Sertoli cells

Front 112

Myoid cells

Back 112

muscle-like cells in basement membrane of seminiferous tubules that contract mildly to help move sperm & fluid through tubules

Front 113

Sertoli cell functions

Back 113

sustentacular cells

pyramid-shaped cells lying next within the seminiferous epithelium

nurse cells that nurture and provide structural support for sperm cells during development

secrete testicular fluid in cavity of seminiferous tubules

phagocytic and engulf remains of degenerate germ cells

provide blood-testis border

# determined at puberty

secrete androgen binding proteins

secrete inhibin and Mullerian-inhibiting substance

produce enzymes that convert testosterone to DHT or estrodiol

Front 114

Blood-testis border

Back 114

made up of sertoli cells

protects spermatocytes and spermatids from autoimmune attack

Front 115

Leydig Cells

Back 115

presents in interstitial spaces outside of the seminiferous tubules

synthesize and secrete androgenic steroid hormones like testosterone when given LH

Front 116

Strong/potent androgens

Back 116

DHT

Testosterone

Front 117

Weak androgens

Back 117

Androstenedione

DHEA

Front 118

DHT function

Back 118

causes growth of facial hair, prostate, penis, and scrotum

Front 119

Androgen function

Back 119

stimulates growth and maintainance of male reproductive tissues

stimulate muscle growth

enhances libido in both men and women

Front 120

Androgen Binding Protein (ABP)

Back 120

secreted by Sertoli cells in tubular lumen where it combines with testosterone and DHT

Front 121

Anabolic Steroids

Back 121

Like Androstenedione, (weak androgen)

increases muscle mass

excess androgen can induce testis shrinkage and infertility

Side effects: Acne, High BP, excessive aggression

In females: causes infertility, breasts atrophy, facial hair, deepening voice, clitoral enlargement

Front 122

Depo-provera

Back 122

An exogenous progesterone which is a contraceptive for females and a chemical castrating agent for males

Front 123

Prostatic Urethra

Back 123

region of urethra surrounded by prostate gland and at area where ejaculatory ducts enter the urethra

Front 124

Membraneous Urethra

Back 124

region of urethra that passes through the pelvic cavity

Front 125

Spongy (Cavernous) Urethra

Back 125

region of urethra passing through penis

Front 126

Urethral orifice

Back 126

where sperm leave the body

Front 127

Sex Accessory Glands

Back 127

Glands that secrete fluid into ducts that join the sex accessory ducts amd mices with sperm (seminal plasma) to form semen (semial fluid)

Seminal vesicle
Prostate gland
Bulbourethral glands

Front 128

Seminal Vesicles

Back 128

Paired pouch on the base of the urinary bladder

secrete seminal plasma
(high in fructose)

produce the majority of seminal plasma

Front 129

Prostate

Back 129

single donate shaped organ, the size of a chestnut

Lies below urinary bladder and surrounds the prostatic urethra

Alkaline secretion of this gland makes up 13-33% of seminal plasma

Front 130

Benign Prostate Hyperplasia (BPH)

Back 130

occurs in 50% of men over 45 and is a non-cancerous enlargement of gland that occludes (blacks) the urethra

Caused by high testosterone conversion to DHT. DHT stimulates prostate to enlarge

Front 131

Finasteride

Back 131

extract from saw palmetto fruit that reduces development of Benign Prostate Hyperplasia

Inhibits 5 alpha reductace to slow down development of DHT

Front 132

Prostate Cancer

Back 132

2nd leading cause of cancer in men

diagnosed with blood test of PSA

increase in men with diets rich with animal fat

reduced by frequent sex, consuming tomato paste

Front 133

Corona glandis

Back 133

round ridge on posterior end of glans penis

Front 134

Penile prepuce

Back 134

foreskin

skin covering shaft extends in a loose fold over glands

Front 135

Penis shaft

Back 135

contains 3 cylinders engorged with blood during erection

Front 136

Corpora cavernosa

Back 136

two dorsal cylinders of the shaft

Front 137

Corpus spongiosum

Back 137

one cylinder in bottom of shaft with spongy urethra running through it

Front 138

Tunica dartos

Back 138

layer of smooth muscle under skin that contracts or relaxes in response to temperature

Front 139

Cremaster

Back 139

skeletal muscle under tunica dartos that contracts when thigh is stroked (excitement, fear, anxiety)

Front 140

Guevedoces

Back 140

5 alpha reductase inefficiency

no DHT produced, no male physical characteristic

MIS active, so mullerian duct tissue

With females external characteristics but high spike in testosterone at birth tissue that respond to tissue begins to respond to testosterone

Clitoris becomes penis size in puberty

Front 141

Testicular Feminization Syndrome

Back 141

XY females

Lack of receptors for androgen in target tissues

No mullarian ducts, female exterior characteristics, but with woffian counterparts inside

Front 142

Penile Agenesis

Back 142

Lack of penis because genital tubercles did not form

Front 143

Bifid Penis

Back 143

genital tubercle branches resulting in a forked or bifid penis

Front 144

Micropenis

Back 144

When the pituitary gland in male fetus is underdeveloped

Front 145

How is Double uterus with double vagina formed?

Back 145

Mullerian ducts did not completely fuse

Front 146

Fertilization

Back 146

Fusion of nucleus of a haploid male gamete and female gamete to form a diploid individual

Both gametes travel in female reproductive tract to meet in oviduct

Both gametes go through important physical and biochemical changes

Front 147

Fertilization = Conception

Back 147

Both sperm and ova travel in the female
reproduction tract for a rendezvous in
the oviduct

While traveling, both the sperm and the
ova go through important physical and
biochemical changes

Front 148

# Sperm produced per day?

Back 148

200 million sperm are produced each day

Front 149

seminal plasma

Back 149

Secretions of the male accessory glands mixed in ejaculatory duct
(prostate gland and seminal vesicle)

Contributes to maintenance, maturation, and
transport of sperm

Front 150

seminal fluid

Back 150

Sperm travels up vas deferentia and mixes
with seminal plasma in the ejaculatory duct
to form semen (seminal fluid)

Front 151

Prostaglandins in seminal fluid

Back 151

Prostaglandins in seminal fluid
contract smooth muscles in the
vasa deferentia, thus aiding sperm
passage during ejaculation

Front 152

Human semen characteristics

Back 152

Creamy texture with gray to yellow color

Front 153

How many sperm are produced each day?

Back 153

200 million

Front 154

How is seminal plasma produced?

Back 154

Secretion of male accessory glands
(prostate gland and seminal vesicle)

Front 155

What happens between sperm traveling in vas deferentia and ejaculatory duct?

Back 155

it mixes with seminal plasma to form semen (seminal fluid)

Front 156

Fertility index

Back 156

minimum qualifications for
male fertility:
≥ 20 million sperm/ml
≥ 40% being able to swim
≥ 60% are normal shape and size

Front 157

Sperm head structure

Back 157

contains an elongated haploid nucleus surrounded by nuclear membrane

Front 158

Acrosome

Back 158

membrane bound vesicle
external to nucleus that fits over the
head of the sperm like a cap

Acrosome is full of enzymes important in the penetration of the ovum

Front 159

Oviduct ampullary-isthmic junction

Back 159

most common site of
fertilization

Front 160

How much sperm make it to the egg?

Back 160

20 - 200 reach the egg

Front 161

Semen coagulation

Back 161

about one minute after deposition
into the vagina, the semen becomes thicker which may
prevent sperm loss from vagina

Front 162

Semen liquefaction

Back 162

about 20 minutes after deposition
into vagina, semen again liquefies which enables sperm to
swim faster toward cervix

Front 163

How to sperm climb up the uterine wall?

Back 163

by beating their tails
+
uterine muscle contractions and cilia movement play a more important role in facilitating sperm transport up the uterine wall

Front 164

sperm behavior in isthmus of oviduct

Back 164

sperm tail beating is reduced while they “wait’
for ovulation to occur

After ovulation, sperm move up to the
ampullary-isthmic junction where it meets the
ovum that has traveled from the ovary
through the oviductal infundibulum & ampulla

Front 165

Where does the fertilization of the ovum by sperm occur?

Back 165

Fertilization of ovum by sperm usually occurs
at the ampullary-isthmic junction

Front 166

In what direction does the oviductal cilia in deep recesses beat?

Back 166

Oviductal cilia in the deep recesses beat toward the ovary to help move sperm

Front 167

In what direction does the oviductal cilia in the ridges beat?

Back 167

Oviductal cilia in the ridges beat toward the uterus to help move egg

Front 168

Is freshly ejaculated sperm capable of fertilization?

Back 168

no

Front 169

Fertilization

Back 169

Sperm passage through cumulus oophorus

Sperm passage through zona pellucida

Sperm attachment to egg plasma
membrane

Cortical reaction

Front 170

What happens genetically during fertilization?

Back 170

Completion of second meiotic division of egg

Formation/fusion of sperm and egg
pronuclei

Front 171

Sperm passage through
cumulus oophorus

Back 171

As sperm enters the the cumulus oophorus, the enzyme hyaluronidase on the sperm
head dissolves hyaluronic acid, a
component of cementing material found between cells

Hyaluronic acid breakdown enables sperm to reach the zona pellucida

Front 172

cumulus oophorus

Back 172

Cumulus oophrus is a layer of loosely
packed follicle cells that surround the
ovulated ovum

Front 173

The cortical reaction

Back 173

Once a sperm has penetrated an egg, a
defense is mounted to prevent another sperm
from penetrating the egg

Cortical granules under the egg cell
membrane release enzymes that debilitate
ZP3 and ZP2 which prevents attachment of
additional sperms which prevents polyspermy

This cortical reaction is the first step in a
series of biochemical and physical changes
known as egg activation

Front 174

Completion of second meiotic stage

Back 174

Ovulated egg is still arrested in second
meiotic stage

Penetration of egg by sperm initiates
egg activation resulting in completion
of second meiotic division

Front 175

Formation of sperm pronuclei

Back 175

Soon after sperm nucleus enters egg,
its nuclear membrane breaks down

Sperm DNA re-condenses as a result of
exposure to egg cytoplasm

A new membrane is formed to enclose the sperm pronucleus

Front 176

Who do we inherit mitochondria from?

Back 176

All our mitochondria are inherited from
our mothers

Front 177

blastomeres

Back 177

Zygote divides mitotically to form two
daughter cells (mirror planes)

Front 178

Conception = fertilization

Back 178

when a sperm
and an egg fuse to become a zygote

Front 179

Gastrulation

Back 179

the process of cell
movements by which a developing embryo
forms distinct layers that later grow into
particular organs

Front 180

Pregnancy
Week 0-2

Back 180

Preembryo development:
developing organism between between
fertilization and implantation at approximately 7
days after fertilization (can be as long as 10 days)

Front 181

Biological age

Back 181

Average time
of 38 weeks (266 days) from
fertilization/conception to birth and is divided into
3 trimesters each around 3 months long

Front 182

Gestational age

Back 182

the period of development of
offspring during pregnancy

Front 183

Gestational age definition in clinical medicine

Back 183

duration since day 1 of last menstrual period
which is approximately 2 weeks longer than
duration since conception

Front 184

Pregnancy
Week 3-8

Back 184

Embryo development: prenatal
stage between establishment of implantation
through 8th week after fertilization

Front 185

average
gestational age of a term birth

Back 185

40 weeks (280
days)

Front 186

Onset of pregnancy
Clinical medicine definition:

Back 186

day 1 of
last menstrual period, which is on
average two weeks before
conception

Front 187

Onset of pregnancy
Biological definition:

Back 187

conception

Front 188

Onset of pregnancy
General public definition:

Back 188

1-2 days
after a missed menstrual period or
when the pregnancy test is positive,
which is on average two weeks after
conception (when hCG is detectable)

Front 189

Positive signs of pregnancy

Back 189

• Detection of fetal heartbeat

• Feeling the fetal movement

• Visualization of fetus by ultrasound or
fetoscopy

Front 190

Human chorionic gonadotropin (hCG) hormone

Back 190

Human chorionic gonadotropin (hCG) hormone
is produced by blastocyst and placenta of embryo
and fetus

has similar biological activity as LH

its detection present in blood and urine indicates pregnancy (only 15 days after conception or day after missed menses)

Can have false positive or false negative

Front 191

morula

Back 191

ball of 8 to 32 cells by 3rd day after fertilization

Occurs in zygote after several mitotic divisions after fertilization

The preembryo continues to divide as it
passes down the oviduct to the uterotubal
junction

Movement of the developing preembryo is
facilitated by the beating of oviductal cilia in
the uterine direction

Front 192

blastocyst

Back 192

Blastocyst: ball made of single outer layer of
cells (trophoblast) just inside the zona
pellucida surrounding a fluid-filled cavity
called the blastocoel

3-4 days after fertilization the preembryo
enters the uterus and is a mass of cells called
the blastocyst

Front 193

trophoblast

Back 193

single outer layer of
cells

Front 194

blastocoel

Back 194

fluid-filled cavity in blastocyst

Front 195

Inner cell mass in blastocyst

Back 195

clump of cells
near one end of blastocyst underneath the
trophoblast layer

gives rise to the embryo and
also is the source of embryonic stem cells

Front 196

When does implantation occur?

Back 196

Dividing ball of cells moves through the
oviduct to the uterus where
implantation occurs approximately 7
days after conception (can be as long
as 10 days)

Front 197

What does the Corpus Luteum do in implantation

Back 197

Corpus luteum secretes modest levels of
estrogen and high levels of progesterone
which primes the uterus and makes the
endometrium more vascular, secretory, and
ready for implantation

Front 198

Trophoblast during implantation

Back 198

In early phase of implantation, the
trophoblast differentiates into an outer
syncytiotrophoblast and an inner
cytotrophoblast

Front 199

Syncytiotrophoblast

Back 199

Syncytiotrophoblast secretes
proteases that breakdown cells of the
uterine endometrium

Front 200

deciduoma response

Back 200

Cells of uterine stroma demonstrate a
deciduoma response and multiply
rapidly and form a cap over blastocyst
which makes implantation complete

Front 201

Where does sinusoids full of maternal blood develop?

Back 201

Sinusoids full of maternal blood develop within the syncytiotrophoblast

Front 202

Preembryonic sequence: Day 7

Back 202

implantation begins (may occur on day 10)

Front 203

Preembryonic sequence: Day 15

Back 203

first missed menses/positive pregnancy test

Front 204

During implantation, are fetal cells genetically different than those of the mother?

Back 204

Yes

Front 205

Are histocompatibility molecures (HLAs) found on most nucleated cells found on placental cells?

Back 205

No, they are not found on placental cells, explains why implantations are not routinely rejected by mother's tissue

Front 206

What does the inner cell mass differentiate to during early embryonic development?

Back 206

the bilamniar embryonic disc which consists of two layers of cells: the epiblast and hypoblast

Front 207

Extraembryonic membrane

Back 207

sustains embryo during intrauterine development

Hypoblast, along with epiblast and trophoblast,
contribute to development of extraembryonic
membranes

Front 208

Epiblast

Back 208

only epiblast layer gives rise to embyro proper

Epiblast splits into 3 germ layers: ectoderm,
mesoderm, endoderm

Front 209

Early embryonic development:
ectodermal layer origin

Back 209

• Nervous system
• Epidermis of skin, hair, nails, and tooth
enamel

Front 210

Early embryonic development:
mesodermal layer origin

Back 210

• Skeleton
• Notochord that develops into vertebral
column
• Muscles
• Heart & circulatory system
• Kidneys
• Gonads
• Deep layers of skin

Front 211

Early embryonic development:
endodermal layer origin

Back 211

Digestive tube and the liver, gall
bladder, and pancreas that bud off the
gut tube
• Respiratory tube including the lung

Front 212

Extraembryonic membranes

Back 212

Inner cell mass produces 3 of the 4
extraembryonic membranes:
• Yolk sac (mainly vestigial in humans)
• Allantois (mainly vestigial in humans)
• Amnion

4th membrane is the chorion and is derived
from cytotrophoblast

Front 213

Extraembryonic membranes:
yolk sac

Back 213

Endoderm-lined membrane that
surrounds the blastocoel (yolk sac
cavity)

Vestigial & non-functional in humans
but is very important in birds that lay
eggs

Degenerates early in embryonic
development in humans

Front 214

Extraembryonic membranes:
amnion

Back 214

Grows over forming embryo

Amniotic fluid supports and protects the
fetus against mechanical shock and
provides water and other materials to fetus

Front 215

Extraembryonic membranes:
chorion

Back 215

Derived from the cytotrophoblast

Chorion eventually fuses with amnion + important part of placenta

Front 216

Placenta

Back 216

Placenta serves as a nutrient, respiratory, and
excretory organ for fetus

Through placenta fetus receives oxygen, glucose,
growth factors, and other nutrients and eliminates
carbon dioxide and other waste products

Front 217

What cannot pass through chorionic villi and into the fetal blood vessels?

Back 217

Molecules larger than 500 molecular weight will
not pass through the chorionic villi and into fetal
blood vessels

Front 218

chorionic villi

what day?

Back 218

fingerlike projections of the cytotrophoblast that extend through the syncytiotrophoblast and toward the vascular uterine stroma on day 14

Front 219

“decidua” of the pregnant uterus

Back 219

As fetus and placenta grow, the stratum
functionalis of endometrium is transformed
into the “decidua” of the pregnant uterus

Front 220

Decidua basilis

Back 220

maternal part of placenta

Front 221

Decidua capsularis

Back 221

result of deciduoma
response with overgrowth of endometrium

Front 222

Decidua parentalis

Back 222

endometrium not
directly connected to fetus

Front 223

Umbilical cord

Back 223

Connects fetus with the placenta

Front 224

What is the umbilical cord derived from?

Back 224

Derived from body stalk that is structure
connecting embryo and chorion

Front 225

How wide and long is the cord at birth?

Back 225

At birth, cord is 0.3-1.0 inches diameter and 20-22
inches long and is covered with amniotic
membrane

Front 226

How many vessels does the umbilical cord have?

What do they do?

Back 226

Two umbilical arteries carry de-oxygenated fetal
blood to the placenta
(reference: fetal heart)

One umbilical vein carries oxygenated blood from
the placenta to the fetus

Front 227

Wharton’s jelly

Back 227

Vessels within cord are cushioned by a gelatinous substance called Wharton’s jelly

Front 228

Dizygotic fraternal twins

Back 228

two genetically distinct zygotes form & two embryos implant into uterus

Implant spatially separate: two separate
placentas, chorions, and amnions

Implant close together: single placenta, fused
chorions, and two amnions (ALWAYS)

Front 229

Monozygotic identical twins

Back 229

develops when
inner cell mass of blastocyst divides, producing
two embryos with:

a single placenta and chorion (unless splitting of early morula produces monozygotic twins with separate
amnions, chorions, & separate or fused placentas),
but two amniotic sacs (ALWAYS)

Front 230

When in embryonic development does the preembryo form as a flattened disc all three germ layers: ectoderm, mesoderm, and endoderm

Back 230

By the end of the second week post-conception

Front 231

When in embryonic development does all major internal and external structures take shape

Back 231

Week 2-8

Front 232

teratogens,
mutagens

Back 232

developing embyro is very sensitive to disturbances (teratogens,
mutagens) that could result in death or congenital
malformations

Front 233

Embryonic development: week 3
embryonic disc shape

Back 233

Week 3 of development, the flat, trilaminar
embryonic disc begins to curl under to form a
sausage-like shape

Front 234

Embryonic development: week 3 Neural tube

Back 234

Neural tube develops along embryo back and
develops spinal cord and brain

A series of lumps (somites) form along either side
of neural tube which develop into the vertebrae,
ribs, and muscles in the back

Front 235

Embryonic development: week 4
Embryo shape

Back 235

2 mm long embryo with C shape at
beginning of week 4

Front 236

Embryonic development: week 4
eyes

Back 236

Eyes began to form on head

Front 237

Embryonic development: week 4
ear

Back 237

Inner ear development begins

Front 238

Embryonic development: week 4
neck area

Back 238

Pharyngeal arches develop in neck
area which will develop into jaws, ear
and other structure

Front 239

Embryonic development: week 4
Heart

Back 239

Heart forms and begins beating

Front 240

Embryonic development: week 4 extremities

Back 240

Tiny arm and leg buds develop

Front 241

Embryonic development: week 5
brain

Back 241

Rapid growth of brain

Front 242

Embryonic development: week 5
extremities

Back 242

Arm buds flatten and hands
become paddle shaped

Front 243

Embryonic development: week 5
length

Back 243

1 cm in length by end of week 5

Front 244

Embryonic development: week 6
head

Back 244

Head/brain continues to grow

Front 245

Embryonic development: week 6
extremities

Back 245

leg bud becomes paddle shaped

hand rays indicate positions of digits

Front 246

Embryonic development: week 6
tail

Back 246

Distinct tail is still present

Front 247

Embryonic development: week 7 extremities

Back 247

Toe rays form indicating position of
digits

Front 248

Embryonic development: week 7
tail

Back 248

tail is diminished

Front 249

Embryonic development: week 8 length

Back 249

1.25 inches long by the end of week 8

Front 250

Embryonic development: week 8
eyes

Back 250

Eyelids have grown to meet each other and
fuse so eyes are closed

Front 251

Embryonic development: week 8
extremities

Back 251

Fingers and toes can be clearly seen,
however, a thin sheet of webbing still exists
between each digit

Front 252

Embryonic development: week 8 tail

Back 252

tail has disappeared

Front 253

Embryonic development: week 8
appearance

Back 253

looks human

Front 254

Week 12 (end of first trimester (3 month))
fetus

Back 254

fetal heart rate can be heard with a
stethoscope

Fetus can react to stimuli and fetal
movements begin, however mom can not
yet feel these movements

Front 255

Month 4-5 gestation
fetus

Back 255

Mom may begin to feel fetus moving

Front 256

End of month 6 (2nd trimester)
skin

Back 256

Skin grows layer of downy hair (lanugo)

Skin covered with protective layer of
fatty secretions called vernix caseosa

Front 257

3rd trimester: which months is it?

Back 257

months 7, 8, & 9

Front 258

3rd trimester: fetus

Back 258

Fetus adds layers of fat and loses its
wrinkled appearance

Front 259

3rd trimester: lungs

Back 259

lungs mature

Front 260

What's the limiting factor for survival of premature infants?

Back 260

The limiting factor for survival of
premature infants is lung development

Front 261

Fetus derives what nutrients from Mother's blood via the umbilical veins?

Back 261

glucose
amino acids
fatty acids
vitamins
salts
minerals

Front 262

What products are delivered to the placenta by umbilical arteries?

Back 262

Carbon dioxide
other waste products

Front 263

when are fetal kidneys functional?

Back 263

Fetal kidneys are functional
throughout fetal period

Front 264

How much urine do fetal kidneys produce in a day?

Back 264

Fetal kidneys produce
450 ml of urine a day late in
pregnancy which is excreted into
amniotic fluid

Front 265

How much amniotic fluid does the fetus swallow each day in late pregnancy?

Back 265

In late pregnancy, the fetus swallows
about 500 ml of amniotic fluid each
day

Front 266

What is the oxygenating unit for the fetus?

Back 266

The placenta is oxygenating unit for
fetus

Front 267

ductus arteriosis

Back 267

shunt connecting the (right ventricle) pulmonary artery to the aortic arch (blood bypasses the lungs)

Front 268

How does oxygen get picked up by the fetus from placenta?

Back 268

The deoxygenated blood reaches the
placenta via the umbilical arteries (2),
where it releases carbon dioxide and
picks up oxygen
• Oxygenated blood

Front 269

How does oxygen enter into the fetal heart?

Back 269

Oxygenated blood travels in umbilical
vein back to the right side of the fetal
heart (oxygenated blood enters in the adult heart through the left atrium)

Front 270

foramen ovale

Back 270

hole between right & left
atria where blood is exchanged between the
right side and left side of heart

Front 271

where does the blood go after the right ventricle (in embryo)?

Back 271

Blood is transported from the right
ventricle directly to the aorta via the
ductus arteriosis (pulmonary artery connects to the descending aorta)

Front 272

What % of preembryos and embryos die within the first
three weeks of life?

Back 272

50% of preembryos/embryos die within the first
three weeks of life

Front 273

Of confirmed pregnancies, how many miscarry?

Back 273

Of confirmed pregnancies, 15-20% miscarry

Front 274

Chromosomal abnormalities account for how many % spontaneously aborted?

Back 274

Chromosomal abnormalities account for 42% of
spontaneously aborted

Front 275

Chromosomal abnormalities occur in how many
newborns?

Back 275

Chromosomal abnormalities occur in 1/200
newborns

Front 276

What are viral infections that harm embryo or fetus?

Back 276

HIV
chickenpox
herpes simplex
rubella
mumps
parvovirus

Front 277

What are bacterial infections that harm embryo or fetus?

Back 277

syphilis
TB
typhoid

Front 278

When does Teratogens, mutagens, & other
agents that damage fetuses occur?

Back 278

4-7 weeks during gestation

Front 279

What are teratogens, mutagens, & other
agents that damage fetuses

Back 279

recreational drugs
some pharmaceutical drugs
alcohol

Front 280

What is an ultrasound used for?

Back 280

Ultrasound is used to assess fetal anatomy
and movement and placenta position

Front 281

What can be used to estimate likelihood that a fetus has Down's syndrome

Back 281

Multiple serum marker test from maternal
blood: hCG (human chorionic gonadotropin), etc
estimate likelihood that a fetus has Down’s
syndrome, however this test is not definitive

Front 282

amniocentesis

Back 282

a type of fetal evaluation where a needle is inserted through abdominal and uterine wall into amniotic fluid with ultrasound

Front 283

When is it, in life, is it recommended that a woman goes through amniocentesis?

Back 283

Recommended in women over 34 years, or
women with family history of genetic
disorders

Front 284

When is amniocentesis performed?

Back 284

Procedure performed between 14th and
16th week of pregnancy (biological
definition)

Front 285

When, in life, is chorionic villus sampling (CVS) recommended?

Back 285

Recommended in women over 34 years, or women with
family history of genetic disorders

Front 286

How does the risk of CVS compare to amniocentesis

Back 286

Higher risk of inducing miss-carriage than with
amniocentesis

Front 287

When is CVS preferable to amniocentesis?

Back 287

With CVS get results earlier than amniocentesis, which is
preferable if the pregnancy is going to be terminated
based on the test results

Front 288

Induced abortion:
1st trimester

safety?

Back 288

Relatively safe

Front 289

How many % of all induced abortions in the USA are in the first trimester?

Back 289

87% of all induced abortions in the USA
are in the 1st trimester

Front 290

What are ways to induce abortion in the first trimester?

Back 290

Medical abortion from taking pill or
surgical abortion that uses aspiration
and instruments to empty contents of
uterus

Front 291

How is Embryonic period abortion induced in the first trimester?

Back 291

Embryonic period abortion induced by
prostaglandins and mifepristone

Front 292

Mifepristone and how does it work?

Back 292

RU486 referred as the abortion
pill acts by preventing progesterone action by
blocking progesterone receptors

Front 293

When can Mifepristone be taken during pregnancy?

Back 293

Mifepristone can be taken within first 35 days
post-conception to induce a miscarriage and is
sometimes taken with misoprostol (prostaglandin)
vaginal suppository that softens the cervix to
facilitate the release of miscarriage out of cervix

Front 294

What is the most frequent used method of abotion in 1st trimester abortion?

Back 294

vacuum aspiration

Front 295

Vacuum aspiration

Back 295

1st trimester abortion where Vacurette tube is placed through cervix into
uterus and is connected to a suction devise

Front 296

What happens in vacuum aspiration if the material is not completely removed by suction?

Back 296

the endometrium is scraped with a
curette

Front 297

When does vacuum aspiration occur during pregnancy?

Back 297

5-11 weeks after conception

Front 298

dilation and curettage

Back 298

a form of 1st trimester induced abortion where the endometrium is scraped with a
curette which is inserted through the
cervix

Front 299

When, during pregnancy, is dilation and curettage done?

Back 299

Done in 8th - 14th week after
conception

cervix is dilated with laminaria

Front 300

Laminaria

Back 300

(brown algae)

small tube that dilates cervix abd absorbs moisture

Front 301

What can be administered in the 2nd trimester to induce abortion?

Back 301

Administration of intra-amniotic saline, urea, glucose, or
prostaglandin alone or in combination to terminate the pregnancy and induce (early) delivery

Front 302

what is dilation and evacuation?

what is used?

Back 302

Abortion technique used during the 2nd trimester

Dilate cervix with Laminaria

Uterine contents removed using
suction, curettes, and forceps

Front 303

Administration of intra-amniotic

Back 303

Abortion technique used in second trimester that uses saline, urea, glucose, or prostaglandin to terminate and induce early pregnancy

Front 304

How do you explain the ethnic variations in dizygotic twin frequency?

Back 304

Ethnic differences appear to be in part due to ethnic variations in follicle-stimulating hormone

Front 305

1 in how many births in a rural community of Yoruba in Nigeria is a dizygotic twin?

Back 305

1/20

Front 306

1 in how many births of black females is a dizygotic twin?

Back 306

1/80 in black females

Front 307

1 in how many births of white females is a dizygotic twin?

Back 307

1/100

Front 308

1 in how many births of Japanese is a dizygotic twin?

Back 308

1/155

Front 309

How does heredity trends play a role in Dizygotic twin?

Back 309

Heredity of mother is more important than father

Front 310

What is the rate of twinning at puberty?

Back 310

near 0%

Front 311

when is the peak levels of twinning?

why?

Back 311

age 37

FSH levels are the heightest

Front 312

How does parity relate to the rate of twinning?

Back 312

Rate of twinning increases with parity: the more children a woman has had the greater the likelihood her next pregnancy will be twins

Front 313

How does the usage of oral contraceptives effect twinning?

Back 313

Increased fecundity and higher rate of dizygous twins reported in women who conceive within one month after stopping oral contraceptives, but not during subsequent months; this appears to be due to the sudden release of pituitary gonadotropin in amounts greater than usual during the first spontaneous cycle after stopping oral contraceptives.