Embryogenesis and Development

Question 1

Ampulla of the fallopian tube

Answer 1

Site of fertilization

Question 2

Fraternal (dizygotic) twins

Answer 2

result from the fertilization of two eggs by two different sperm

Question 3

Identical (monozygotic) twins

Answer 3

result from the splitting of a zygote in two

Question 4

Morula

Answer 4

A solid mass of cells

Question 5

Blastula (blastocyst)

Answer 5

has a blastocoel and 2 different cell types: trophoblasts and inner cell mass

Question 6

Trophoblasts become

Answer 6

placental structures

Question 7

Inner cell mass becomes

Answer 7

the developing organism

Question 8

How is the placenta formed?

Answer 8

The blastula implants in the endometrial lining and does this

Question 9

Chorion

Answer 9

Contains chorionic villi, which penetrate the endometrium and create the interface between maternal and fetal blood

Question 10

What supports the embryo before the placenta?

Answer 10

The yolk sac

Question 11

Allantois

Answer 11

Involved in early fluid exchange between the embryo and the yolk sac

Question 12

Amnion

Answer 12

produces amniotic fluid

Question 13

Gastrulation

Answer 13

The archenteron is formed with a blastopore at the end

Question 14

Notochord

Answer 14

Includes a group of overlying ectodermal cells to form neural folds surrounding a neural groove

Question 15

Neural tube

Answer 15

the neural folds fuse to form this, which becomes the CNS

Question 16

Neural crest cells

Answer 16

become the PNS

Question 17

Tetratogens

Answer 17

substances that interfere with dev., causing defects and even death

Question 18

Determination

Answer 18

the commitment to a specific cell lineage accomplished by segregation during mitosis and morphogens

Question 19

How can cells respond to morphogens?

Answer 19

They must have competency

Question 20

Totipotent cells

Answer 20

Differentiate into all cell types

Question 21

Pluripotent cells

Answer 21

Differentiate into all 3 germ layers and their derivatives

Question 22

Multipotent cells

Answer 22

Differentiate into a specific subset of cell types

Question 23

Foramen ovale shunt

Answer 23

Connects the right atrium to the left atrium, bypassing the lungs

Question 24

Ductus arteriosus

Answer 24

Connects the pulmonary artery to the aorta, bypassing the lungs

Question 25

Ductus venosus

Answer 25

Connects the umbilical vein to the inferior vena cava, bypassing the liver

Question 26

1st trimester dev.

Answer 26

Organogenesis

Question 27

2nd trimester dev.

Answer 27

tremendous growth, movement, face becomes human

Question 28

3rd trimester dev.

Answer 28

rapid growth and brain dev., transfer of antibodies

Question 29

Birth

Answer 29

cervix thins out, the amniotic sac ruptures. uterine contractions, birth. placenta and umbilical cord are expelled.