510-2

Question 0

When does fetal development occur?

Answer 0

9-38 weeks

Question 1

How long is embryonic development?

Answer 1

8 weeks

Question 2

What is the ampulla?

Answer 2

Region of the Fallopian tube where fertilization occurs (12-24hrs)

Question 3

What is ovulation?

Answer 3

When an oocyte is released from an ovary and swept into the Fallopian tube by ciliated epithelia. Each ovary ovulates every other month.

Question 4

What is follicle stimulating hormone (FSH)?

Answer 4

Stimulated the follicle to grow. This hormone is often used to treat women with infertility issues because it stimulates the growth and production of multiple oocytes.

Question 5

What is the corona radiata?

Answer 5

The first layer of protection that a sperm must break through.

Question 6

What is the zona pellucida?

Answer 6

The second layer the sperm must break through. This layer is like an shell composed of glycoproteins.

Question 7

What is the acrosome?

Answer 7

Vesicle in the tip of the sperm that has digestive enzymes used to break down the zona pellucida (acrosome reaction)

Question 8

What is polyspermy?

Answer 8

When more than one sperm fertilizes an egg. This results in zygot death because of the mismatched chromosomes (69).

Question 9

What are the 3 stages of oocyte penetration?

Answer 9

Stage 1: sperm penetrates corona radiata
Stage 2: acrosome reaction as sperm breaks through zona pellucida
Stage 3: sperm breaks through oocyte membrane and loses its own membrane triggering the zona reaction

Question 10

What is the zona reaction?

Answer 10

When a sperm penetrates the oocyte membrane a calcium mediated change in the zona pellucida prevents other sperm from fertilizing the egg.

Question 11

What is a zygote?

Answer 11

A fertilized egg (12-24 hrs)

Question 12

What is pluripotency?

Answer 12

Early stage cells can differentiate into a variety of things but lose the potential to differentiate with each cell division because the environment changes (especially after compaction during the 8 to 16 cell transition)

Question 13

What is a blastomere?

Answer 13

A cell in the 2, 4, 8, or 16 cell zygote

Question 14

What is a morula?

Answer 14

Solid ball of blastomeres. Forms around the 4th day when the zygote is entering the uterus.

Question 15

What is compaction?

Answer 15

Occurs during the 8 to 16 cell transition when cells make tight and gap junctions.

Question 16

What is paracrine?

Answer 16

Substance produced by one cell that affects another cell (endocrine= paracrine that travels in the blood)

Question 17

What is autocrine?

Answer 17

Substance produced by a cell that affects itself

Question 18

What is a blastocyst?

Answer 18

A blastocyst draws fluid into its blastocele and two layers of cells result: trophoblast and embryoblast. This occurs around 4.5 days.

Question 19

What is an embryoblast?

Answer 19

Layer in the blastocyst that will give rise to the embryo

Question 20

What is the trophoblast?

Answer 20

Outside layer of the blastocyst that will give rise to the placenta

Question 21

What are the 3 layers of the uterus?

Answer 21

1. ) perimetrium- thin outer membrane
2. ) myometrium- muscular middle layer
3. ) endometrium- vascular middle layer with mucous glands

Question 22

What is implantation?

Answer 22

Growth of the trophoblast into the endometrium (penetrates basement membrane). Usually happens around 6th day

Question 23

What is the syncytiotrophoblast?

Answer 23

Outer layer of the trophoblast with vague cell boarders to aid in blood transfer between mother and fetus

Question 24

What is the cytotrophoblast?

Answer 24

Inner layer of trophoblast composed of large single cells

Question 25

What are the two layers of the embryoblast?

Answer 25

Epiblast (will form the embryo) and Hypoblast (will form the yolk sac)

Question 26

What is the extra embryonic coelom?

Answer 26

Cavity between the hypoblast and trophoblast that takes in fluid to push yolk sac and trophoblast away from eachother and allows for the chorion to develop

Question 27

What is the chorion?

Answer 27

Produces human chorionic gonadotropin (hCG) which keeps the corpus luteum alive and producing progesterone and estrogen to keep the uterus pregnant (used in pregnancy detection)

Question 28

What is gastrulation?

Answer 28

Process of the development of 3 germ layers: ectoderm, mesoderm, and endoderm. Takes place from day 13-19.

Question 29

What does ectoderm give rise to?

Answer 29

Skin, mouth lining, enamel, nervous system

Question 30

What does mesoderm give rise to?

Answer 30

Muscle, bone, blood, lymphatic system, spleen, lungs, heart, reproductive system, and excretory system

Question 31

What does endoderm give rise to?

Answer 31

Lining of the gut, liver, pancreas, bladder, thyroid, parathyroid, and lungs

Question 32

What is mesenchyme?

Answer 32

Undifferentiated connective tissue

Question 33

What is the primitive streak?

Answer 33

Extends from the primitive node caudally. Is controlled by the gene nodal. The primitive node cells produces transforming growth factor B and bone morphogenic protein 4 that stimulate mesoderm growth.

Question 34

What is Fibroblast Growth Factor 8?

Answer 34

Transcription factor that controls the inward migration of cells during gastrulation

Question 35

What are chordin and noggin?

Answer 35

They are expressed by the primitive node and direct differentiation of the mesoderm into the notochord and somites. Play an important role in establishing anterioposterior axes.

Question 36

What did the Hans Spemann experiment show us?

Answer 36

Transplanting the dorsal lip of a blastopore onto another embryo organizes the growth of another head

Question 37

What is goosecoid?

Answer 37

Transciption factor that stimulates chordin to signal for the production of cranial mesoderm. If over expressed can lead to two heads.

Question 38

What is the notochord?

Answer 38

Created by cells migrating anteriorly from the primitive node. has inductive effects on surrounding tissues.

Question 39

What is neurulation?

Answer 39

Take place around the 3rd week. Its when the notochord signals the ectoderm to thicken and become neural ectoderm. This neural plate develops a flap and grooves that eventually fold on itself and create a neural tube (CNS)

Question 40

What are somites?

Answer 40

paired mesoderm on either side of the neural tube that develops into dermis, muscle, tendon, and bone.

Question 41

What is spina bifida?

Answer 41

When the sacral region of the neural tube doesn't close properly

Question 42

What is anencephaly?

Answer 42

When the cephalic region of the neural tube doesn't close properly

Question 43

What is neural crest?

Answer 43

Cells that originate from the ectoderm but are important in a variety of things including formation of dentin and facial cartilage (ex. abnormal NC migration can lead to Treacher Collins Syndroms)

Question 44

When is the embryo most susceptible to teratogens?

Answer 44

3-8 weeks when most organ systems are being established