chapter 16 and 17 text

Question 1

after the nucleus of a sperm and the nucleus of an egg fuse, fertilization is complete, and the new, diploid cell is referred to as a

Answer 1

Zygote

Question 2

The zygote travels down the fallopian tube, heading for the uterus so it can implant in the

Answer 2

Uterine lining

Question 3

As the zygote travels it undergoes what

Answer 3

Cleavage

Question 4

What is cleavage

Answer 4

A rapid series of mitotic divisions that result in a multicellular embryo

Question 5

The zygote divides into 2 cells, then 4 cells, then 8 cells, then 16 cells which at that point the zygote is a solid ball of cells called a

Answer 5

Morula

Question 6

Cell division continues, but the morula becomes filled with liquid, which pushes the increasing number of cells out toward the periphery of the embryos membrane, forming a hollow ball of cells called a

Answer 6

Blastula

Question 7

When does the blastula become a blastocyst

Answer 7

A group of cells inside the blastula become specialized to form the embryo & the blastula becomes a blastocyst

Question 8

The flattened cells along the edge of the blastocyst from the

Answer 8

Trophoblast

Question 9

The fluid-filled cavity is called the

Answer 9

Blastocoel

Question 10

The sphere of larger, rounded cells thats destined to become the embryo is called the

Answer 10

Embryoblast

Question 11

If the blastocyst doesn’t implant in the wall of the uterus, there is no what

Answer 11

Pregnancy

Question 12

If conception occurs, the trophoblast cells of the blastocyst go on to form the

Answer 12

Chorion, which becomes part of the placenta

Question 13

After implanting itself, the developing mass of cells moves inward, forming a ball of cells called a

Answer 13

Gastrula that has 3 layers

Question 14

This is the outer layer of the gastrula, it develops into the skin and nervous systems

Answer 14

Ectoderm

Question 15

The middle layer of the gastrula develops into the muscular, skeletal and circulatory systems

Answer 15

Mesoderm

Question 16

The innermost later of the gastrula gives rise to the linings of your digestive and respiratory tracts, as well as organs such as the liver and pancreas

Answer 16

Endoderm

Question 17

An egg can be fertilized, but a woman isn’t pregnant until the blastocyst is what

Answer 17

Rooted in her uterine wall where it can develop further

Question 18

Every organ in your body forms during the

Answer 18

Embryonic period-the 1st trimester of pregnancy

Question 19

After gastrulation, the specialized cells of the ectoderm, mesoderm, and endoderm begin migrating toward other cells with the same specialty, this cellular migration is referred to as

Answer 19

Morphogenesis, because it gives the embryo a shape

Question 20

Outside the embryo what develops

Answer 20

Specialized membranes

Question 21

The chorion combines with tissues created by the mother to become the

Answer 21

Placenta

Question 22

An organ thats filled with blood vessels and provides a large surface area for the exchange of gases, nutrients, and wastes

Answer 22

Placenta

Question 23

What protects the developing embryo

Answer 23

The amnion surrounds the amniotic cavity, which fills with amniotic fluid

Question 24

The fetal period encompasses the last

Answer 24

6 Months of pregnancy, or the 2nd and 3rd trimesters