Embryology Stuff

Question 1

What are the developmental stages seen in weeks 1-2?

Answer 1

Zygote
Morula
Blastula
Bilaminar disc

Question 2

What are the developmental stages seen in weeks 3-8?

Answer 2

Gastrualtion
Folding
Organogenesis

Question 3

When does gestational age begin?

Answer 3

From 1st day of last normal menstrual period

Question 4

When does embryonic age begin?

Answer 4

At fertilization

Question 5

What are the two cell layers in the week of w 2’s?

Answer 5

Cytotrophoblast

Syncytiotrophoblast

Question 6

Which cell layer produced HCG?

Answer 6

Syncytiotrophoblast

Question 7

The syncytiotrophoblast is lacking what?

Answer 7

A cell boundary

Question 8

What is the 1st sign of gastrulation?

Answer 8

Primitive streak

Question 9

Where does the primitive streak form?

Answer 9

On the caudal end in the former epiblast

Question 10

The cells of the primitive streak migrate and give rise to what?

Answer 10

Mesoderm

Question 11

The primitive node is the originiation of the cells that will migrate toward the cranium and form what?

Answer 11

The notochord

Question 12

From what does the nerual plate form?

Answer 12

Ectoderm

Question 13

What does ectoderm give rise to?

Answer 13

Epidermis
Central and peripheral NS
Eyes
Internal ears

Question 14

What does endoderm give rise to?

Answer 14

Epithelial linings of respirator and digestive tracts
Glands
Liver
Pancreas

Question 15

What does mesoderm give rise to?

Answer 15

Muscles
Blood cells/lining of vessels
Smooth muscle
Serosa

Question 16

As the notochord forms, the embryo lengthens which direction?

Answer 16

Caudal/cranially

Question 17

Notochord instructs formation of what?

Answer 17

Neural plate

Question 18

What are the landmarks on the neural plate?

Answer 18

Folds and grooves

Question 19

The neural plate folds at the midline to form what?

Answer 19

Neural tube

Question 20

Where do neural crest cells come from?

Answer 20

Cells from edge of fusing neural tube migrate and become neural crest cells

Question 21

What do neural crest cells give rise to?

Answer 21

CT of head & neck
Bones & muscles of head and neck
Entire PNS
Melanocytes
Plays role in ectomesenchyme in tooth formation

Question 22

Neural tube becomes what?

Answer 22

Brain and spinal cord

Question 23

At what age does the “Japanese-American greeting” take place?

Answer 23

4th to 8th week

Question 24

When does organogenesis begin?

Answer 24

4th to 8th week

Question 25

What migrates above the prechordal plate to form the heart?

Answer 25

Mesoderm and neural crest cells

Question 26

Somites are instructed by notochord to form what?

Answer 26

Mesoderm on dorsal aspect that will become muscle and bone

Question 27

What contributes to the formation of the pharyngeal arches?

Answer 27

Neural crest

Question 28

Where are rhombomeres found?

Answer 28

Transient structures in hindbrain area of neurotube

Question 29

What is the main contributor toe the pharyngeal arches?

Answer 29

Neural crest cells

Question 30

What forms mesenchymal cells and microglia?

Answer 30

Comes from bone marrow

Question 31

What never is associated with the 1st pharyngeal arch?

Answer 31

CN V

Question 32

What muscles are associated with the 1st pharyngeal arch?

Answer 32

Muscles of mastication Mylohyoid Anterior belly of digastric

Question 33

What are the associated areas of the 1st pharyngeal arch?

Answer 33

Mandible and maxilla tissue | Meckles cartilage

Question 34

What does Meckle's cartilage form?

Answer 34

Bones of ear | Some ligaments

Question 35

What do the grooves of the 1st pharyngeal arch form?

Answer 35

External auditory meatus

Question 36

What does the pouch of the 1st pharyngeal arch form?

Answer 36

Tympanic membrane Tympanic cavity Mastoid antrum Eustachian tube

Question 37

What is the nerve associated with the 2nd pharyngeal arch?

Answer 37

CN VII

Question 38

What muscles are associated with the 2nd pharyngeal arch?

Answer 38

Muscles of facial expression Stapedius Stylohyoid

Question 39

What are the associated areas of the 2nd pharyngeal arch?

Answer 39

Reichert's cartilage (styloid process, stylohyoid ligament, lateral horne of hyoid

Question 40

What do the grooves of the 2nd pharyngeal arch form?

Answer 40

Nothing!

Question 41

What do the pouches of the 2nd pharyngeal arch form?

Answer 41

Contribute to tonsils

Question 42

What forms the anterior tongue?

Answer 42

Lateral and midline swellings (1st pharyngeal arch)

Question 43

Where do the muscles of the tongue come from?

Answer 43

Occipital myotomes - use CN XII

Question 44

What gives rise to the maxillary process and palatal shelves?

Answer 44

Frontonasal prominence and mandibular arch

Question 45

What does meckel's cartilage do in the mandible?

Answer 45

Nothing!

Question 46

Palatal shelves come up vertically from what>

Answer 46

Maxillary prominence