Chapter 3

Question 1

extraembryonic structures formed in second week

Answer 1

amniotic cavity, amnion, umbilical vesicle (yolk sac), connecting stalk, chorioic sac

Question 2

implantation occurs in what time range

Answer 2

6-10 days after ovulation (restricted time period)

Question 3

pinopodes

Answer 3

microvilli of endometrial cells

Question 4

factors making endometrium favorable to implantation

Answer 4

pinopodes, cell adhesion molecules, cytokines, prostaglandins, homeobox genes, growth factors, and matrix metallo-proteins

Question 5

connective tissue cells around implantation site do what

Answer 5

accumulate glycogen and lipids, assume polyhedral appearance

Question 6

embryonic disc layers

Answer 6

epiblast - thick layer of high columnar cells related to amnionic cavity; hypoblast - small cuboidal cells adjacent exocoelomic cavity

Question 7

embryotroph

Answer 7

fluid in lacunar spaces (formed from maternal blood and cellular debris fom eroded uterine glands); provides nourishment

Question 8

10-day human conceptus

Answer 8

completely embedded in the endometrium (closing plug present for 2 days)

Question 9

12-day embryo

Answer 9

adjacent syncytiotrophoblastic lacunae fuse to form lacunar networks; gives sponglike appearance; primordia of intervillous spaces of placenta

Question 10

extraembryonic coelomic spaces

Answer 10

fuse to form extraembryonic coelom; surrounds amnion and unbilicle vesicle

Question 11

secondary unbilical vesicle

Answer 11

extraembryonic endodermal cells that migrate from hypoblast inside primary umbilical vesicle; yolk sac

Question 12

umbilicle vesicle functions

Answer 12

site of origin of primordial germ cells; may have a role in selective transfer of nutrients to embryo

Question 13

primary chorionic villi

Answer 13

end of second week

Question 14

extraembryonic coelom splits extraembryonic mesoderm into 2 layers

Answer 14

extraembryonic somatic mesoderm and splanchnic mesoderm

Question 15

extraembryonic somatic mesoderm

Answer 15

lining the trophoblast and covering amnion

Question 16

extraembryonic splanchnic mesoderm

Answer 16

surrounding umbilical vesicle

Question 17

chorion is formed by

Answer 17

extraembryonic somatic mesoderm and two layers of trophoblast

Question 18

14-day embryo

Answer 18

flat bilaminar disc, hypoblastic cells in a localized area are columnar and form a thickened circular area (prechordal plate)

Question 19

percent ectopic pregnancies in uterine tubes

Answer 19

95-98 percent

Question 20

what can pain from ectopic regnancy be confused with

Answer 20

appendicitis

Question 21

why do ectopic pregnancies (sometimes) give false negatives

Answer 21

rate of Beta-human chorionic gonadotropin production is slower

Question 22

why is bleeding a big problem in ectopic pregnancies

Answer 22

extensive anastomoses between ovarian and uterine vessels

Question 23

risk of maternal death by hemorrage in abdominal pregnancies

Answer 23

increases by a factor of 90 compared to intrauterine and factor of 7 compared to tubal

Question 24

placenta previa

Answer 24

placenta tha partially of completely covers internal Os