Embryonic development & pregnancy

Question 1

Between days 7 and 9 a ______________ forms.

Answer 1

blastocyst

Question 2

The most invasive type of placenta is the diffuse placenta. True or False?

Answer 2

False; the discoid placenta is the most invasive

Question 3

Cotyledonary placentas are found in which animals:

Answer 3

cows & sheep

Question 4

After the 16-cell stage, a ______ is formed which is a packed mass of cells

Answer 4

morula

Question 5

What part of the blastocyst will become the fetus?

Answer 5

inner cell mass

Question 6

What part of the blastocyst becomes the placenta?

Answer 6

trophoblast cells (trophectoderm)

Question 7

The pocket of fluid where the inner cell mass sits

Answer 7

blastocoel

Question 8

What are the 4 functions of the placenta?

Answer 8

protection
nutrition
respiration
hormone production

Question 9

We find this type of placenta in sows and mares

Answer 9

diffuse

Question 10

The outer layer of the placenta is referred to as the…

Answer 10

chorion

Question 11

Where blood crosses over in fetal pigs

Answer 11

chorionic villi

Question 12

In pigs, the maternal side of the placenta is called

Answer 12

rugae

Question 13

In pigs, the fetal side of the placenta is called

Answer 13

areola

Question 14

What do horses have instead of chorionic villi for blood crossover?

Answer 14

microcotelydans

Question 15

Type of placenta found in dogs, ferrets & cats (carnivores mostly)

Answer 15

zonary

Question 16

The area of a zonary placenta that contacts the endometrium (only place where blood can cross over)

Answer 16

central girdle/belt

Question 17

Type of placenta found in humans, primates and rodents

Answer 17

discoid

Question 18

Type of placenta found in cows and sheep

Answer 18

cotelydonary

Question 19

Cotelydons are on the _______ side

Answer 19

fetal

Question 20

Caruncles are on the _______ side

Answer 20

maternal

Question 21

In cows, the caruncles are… (concave/convex?)

Answer 21

convex

Question 22

In sheep the caruncles are…

Answer 22

concave

Question 23

Cotelydonary placentas are considered to be…

Answer 23

noninvasive

Question 24

A cotyledonary placenta is the least efficient - why?

Answer 24

there are more layers for nutrients to travel through between maternal and fetal blood

Question 25

A discoid placenta is the most efficient - why?

Answer 25

Fewer layers for nutrients to travel through between mother and fetus

Question 26

Logarithmic growth chart used to predict fetal age

Answer 26

crown-rump length

Question 27

Energy requirements for a mother during the first stages of gestation are...low/high-why?

Answer 27

low since growth is slow during the first stages

Question 28

Energy requirements for a mother during the last stages of gestation are low/high-why?

Answer 28

high since fetal growth is quicker during the last stages of gestation

Question 29

Cow gestation length

Answer 29

9 months (282 days)

Question 30

Ewe, doe gestation length

Answer 30

5 months (150 days)

Question 31

Sow gestation length

Answer 31

3 months, 3 weeks and 3 days (112-114 days)

Question 32

Mare gestation length

Answer 32

11 months (340 days)

Question 33

Human gestation length

Answer 33

9 months (284 days) -similar to cows

Question 34

Mice gestation length

Answer 34

21 days

Question 35

Elephant gestation length

Answer 35

2 years (616 days)

Question 36

What does crown-rump length growth curve suggest about energy requirements during the first stages of gestation?

Answer 36

Fetal growth is slow during the first 2/3rds so there's not as high of an energy requirement for the mother

Question 37

What are the 4 functions of the 4 placental mebranes?

Answer 37

1.Protection of developing embryo and fetus 2.Nutrition 3.Respiration 4.Hormone production

Question 38

Pregnancy recognition signal in ruminants

Answer 38

Interferon tau

Question 39

Pregnancy recognition signal in swine

Answer 39

Estrogen

Question 40

Pregnancy recognition signal of mice

Answer 40

Prolactin

Question 41

Pregnancy recognition signal of humans

Answer 41

Chorionic gonadotropin

Question 42

Pregnancy recognition signal in horses

Answer 42

Unknown; possibly movement of the embryo for the first 18 days of pregnancy

Question 43

Which type of placenta is most efficient?

Answer 43

Discoid; only 3 layers of tissue to connect placental blood to maternal

Question 44

What is the least efficient type of placenta?

Answer 44

Cotyledonary; 6 layers between fetal and maternal blood supply

Question 45

Maternal side of placenta in pigs

Answer 45

Rugae

Question 46

Fetal side of placenta in pigs

Answer 46

Areola

Question 47

Fetal side of placenta in cows

Answer 47

Cotyledon

Question 48

Maternal side of placenta in cows

Answer 48

Caruncle

Question 49

Species examples with diffuse placentas

Answer 49

Horses and pigs

Question 50

Species examples with cotlyedonary placenta

Answer 50

Cows, sheep, goats (ruminants)

Question 51

Species examples with zonary placenta

Answer 51

Cats (carnivores)

Question 52

Species examples with discoid placenta

Answer 52

Primates and rodents

Question 53

What are the stages of embryonic development? (from ovum to blastocyst?)

Answer 53

ovum -> fertilization -> 1-cell ->2-cell -> 4-cell -> 8-cell -> 16-cell -> morula -> blastocyst

Question 54

A signal that varies among species that will prevent the production of PGF2a so that pregnancy will continue

Answer 54

Maternal recognition of pregnancy

Question 55

What species is an exception to the placental function of hormone production regarding P4

Answer 55

swine

Question 56

Endotheliochorial, 5 layers of tissue between fetal and maternal blood supply

Answer 56

zonary

Question 57

Where fetus connects with maternal

Answer 57

placentomes

Question 58

What does hemochorial mean?

Answer 58

placenta sits in the maternal blood