Chapter 28

Question 1

How long is pregnancy?

Answer 1

Spans from fertilization until birth

Question 2

Conceptus

Answer 2

Developing offspring

Fertilization to birth

Question 3

Gestation Period

Answer 3

Last menstrual period until birth ( roughhly 280 days)

Question 4

Embryo

Answer 4

Conceptus to W8

Question 5

Fetus

Answer 5

Week 9 to Birth

Question 6

Fertilization

Answer 6

Sperm chromosomes combine w/ 2nd oocyte to form fertilized egg (zygote)

Question 7

How long does an oocyte live after ovulation?

Answer 7

12-24 days

Question 8

How long for spermatoza after ejaculation?

Answer 8

24-48 hours

Question 9

What is cleaavage?

Answer 9

Mitotic divisions of zygote

Question 10

When does first clevage occur? What develops?

Answer 10

36 hours - 2 daughter cells (Blastomeres)

Question 11

When does the embryo first meet the uerus? What stage of development/

Answer 11

3-4 days

Blastocyst

Question 12

When does implantation occur?

Answer 12

6-7 days after ovulation (trophoblast implants)

Question 13

What hormone is used to detect early pregnancy? Who produces it?

Answer 13

HCG

Placental Membrane

Question 14

When is the placenta formed?

Answer 14

Fully formed by end of 3rd month

Question 15

What does the placenta secrete?

Answer 15

Hormones (human placental lactogen, human chorionic thryotropin, relaxin)

Waste Exchange

Question 16

What membranes are on the outside of the embryo?

Answer 16

Amnion
Yolk Sak
Allantois
Chorion

Question 17

What is the amnion?

Answer 17

Transparent sac w/ amniotic fluid for protection

Question 18

What is the yolk sak?

Answer 18

Sac that hangs from ventral surface of embryo

Question 19

What fetal organ system does the yolk sak form? Anything else?

Answer 19

digestive tube

- Early blood cells, blood vessels, germ cells

Question 20

What is the Allantois?

Answer 20

• Small outpocketing at caudal end of yolk sak
• ## Base for the umbillical chord

Question 21

What does the allantois become?

Answer 21

Urinary bladder

Question 22

What is the chorion?

Answer 22

Enclosed embryonic body and all other membranes

- Site of gas exchange with maternal circulation

Question 23

What does the chorion become?

Answer 23

Helps form placenta

Question 24

What are the placental germ layers?

Answer 24

Ectoderm, mesoderm, endoderm

Question 25

What does the ectoderm become?

Answer 25

skin and nervous system

Question 26

What does the mesoderm become?

Answer 26

other tissues not formed by endoderm and ectoderm

Question 27

What does the endoderm become?

Answer 27

Epithelial linings of GI, respiratory and uriogenital systems

Question 28

When are organ systems recognizable? What does it signify

Answer 28

at the end of the 8th | - Signals end of embryonic period and beginning of fetal

Question 29

What are the anatomical effects of a pregnancy on a woman's body?

Answer 29

- Uterus expands - Lordosis due to change in center of gravity - Relaxin causes relaxation of pelvic and pubic ligaments

Question 30

What does the placenta produces?

Answer 30

- Human placental lactogen - Human chorionic somatoammotropin - Human chorionic thyrotropin

Question 31

What does placental lactogen and human chorionic somatomammotropin causes?

Answer 31

Maturation of breast, fetal growth and glucose sparing

Question 32

What does human chorionic thyrotropin cause?

Answer 32

Increase maternal metabolism

Question 33

How does the respiratory system change with pregnancy?

Answer 33

Estrogen causes nasal edema and congestion increase in tidal volume dyspena

Question 34

How does the cardiovascular system change with pregnancy?

Answer 34

Blood volume increases 25-40% BP and Pulse Rise Venous return from lower limb impaired

Question 35

What is parturiton?

Answer 35

Giving birth

Question 36

What happens during the last few weeks of pregnancy?

Answer 36

Fetus secretes cortisol

Question 37

What does cortisol stimulate?

Answer 37

Production of oxytocin receptors on myometrium

Question 38

When do practice contractions happen?

Answer 38

Production of oxytocin antagonize calming effects of progesterone

Question 39

When the fetus produces surfactant protein A, what happens?

Answer 39

softening of cervix

Question 40

What does fetal oxytocin cause?

Answer 40

Placental production of prostaglandins

Question 41

What 2 hormones work together as powerful uterine contraction stimulants?

Answer 41

oxytocin | prostaglandin

Question 42

Who initiates birth?

Answer 42

fetus

Question 43

What are the stages of labor?

Answer 43

Dilation Expulsion Placental

Question 44

What is the dilation stage of labor?

Answer 44

Longest period Contractions start weak and grow stronger Cervix thins and dilates to 10 cm Engagement Happens

Question 45

What is engagement?

Answer 45

Head enters true pelvis

Question 46

What is the expulsion stage?

Answer 46

Strong contractions every 2-3 minutes, lasting 60 seconds Urge to push increases ends with delivery of baby

Question 47

What is the placental stage?

Answer 47

Contractions continue after birth of baby to detach placenta which is delivered 30 minutes after birth

Question 48

What is colostrum?

Answer 48

First milk produces, rich in vitamin A, proteins, minerals and IgA antibodies

Question 49

When does true milk production begin?

Answer 49

2-3 days

Question 50

What does suckling promote?

Answer 50

positive feeedback response, increased suckling = more milk letdown

Question 51

What hormone stimulates release of milk?

Answer 51

oxytocin