EmbryologyLecture-Exam II

Question 1

What two layers make up the bilaminal disc?

Answer 1

Epiblast and Hypoblast

Question 2

What are the three layers of the trilaminar disc?

Answer 2

Ectoderm, Intraembryonic Mesoderm, Endoderm

Question 3

How is the intraembryonic mesoderm formed? Start from the primitive streak, use 3 steps

Answer 3

1. Primitive Streak is formed 2.Cells move to primitive streak 3. Epiblast cells migrate down to make both endoderm and i.e. mesoderm

Question 4

What is formed from epiblast->ectoderm?

Answer 4

nervous system, skin

Question 5

What is formed from intraembryonic mesoderm?

Answer 5

body wall structures

Question 6

What is formed from hypoblast->endoderm?

Answer 6

digestive system, respiratory system, urogenital system, PHARYNGEAL POUCHES

Question 7

What are the two parts of the Lateral Mesoderm? Think linings!!

Answer 7

Parietal (Somatic) Layer-lining of body & Visceral Layer-lining around each organ

Question 8

What does the Intermediate Mesoderm form?

Answer 8

Urogenital Structures

Question 9

What type of Mesoderm forms the Somites and Pharyngeal Arches?

Answer 9

PARAXIAL mesoderm

Question 10

What four items are in each somite?

Answer 10

1.Sclerotome(cartilage/bone) 2.Dermatome (Dermis of skin) 3.Myotome (Muscle) 4. A Nerve

Question 11

Which somites become branchial arches?

Answer 11

1-7

Question 12

What 4 items does every branchial arch contain?

Answer 12

A CRANIAL nerve, Artery, Cartilage, Branchial Muscle

Question 13

What nerve is associated with Branchial Arch I? What cartilage and bones?

Answer 13

Trigeminal V….Meckel’s Cartilage, Malleus, Incus Bones

Question 14

What nerve is associated with Branchial Arch II? What Bone, Process, and ligament?

Answer 14

Facial VII….Stapes, Styloid Process, and Stylohyoid Ligament

Question 15

What nerve is associated with Branchial Arch III? What bone?

Answer 15

Glossopharyngeal IX….Hyoid Bone

Question 16

What nerve is associated with Branchial Arch IV? What cartilage?

Answer 16

Vagus X SUPERIOR Laryngeal….Thyroid Cartilage

Question 17

What nerve is associated with Branchial Arch VI? What cartilage?

Answer 17

Vagus X RECURRENT Laryngeal….Cricoid Cartilage

Question 18

THROWBACK which pouch does the INFERIOR Parathyroid gland come from?

Answer 18

3rd pouch

Question 19

Throwback: which pouch does the Superior Parathyroid gland come from?

Answer 19

4th Pouch

Question 20

What comes from the 2nd Pouch? YOU MISSED THIS ON THE EMBRYO TEST

Answer 20

Palatine Tonsils (TWO of them remember?)

Question 21

What arises out of the 1st cleft?

Answer 21

External Auditory Meatus

Question 22

What arises from the 1st pouch?

Answer 22

Auditory tube, remember 1st pouch and 1st cleft join to make the tympanic membrane?!

Question 23

Which pouch does the thymus arise from?

Answer 23

III

Question 24

What structure and formen does the Thyroid Gland arise from?

Answer 24

The tongue and the foramen cecum

Question 25

What three structures give rise to the anterior 2/3s of the tongue? What arch are they from?

Answer 25

The two lateral swellings and the tuberculum impar…1st arch…V get it?!

Question 26

What structure gives rise to the posterior 1/3 of the tongue? What arch?

Answer 26

the COPULA in the 3rd arch…IX get it?!

Question 27

What arch gives rise to the epiglottis?

Answer 27

The 4th arch…X get it?!

Question 28

Are the tongue muscles SM or BM?

Answer 28

Somatic Motor from Occipital Somites

Question 29

What two arches yield the Hyoid bone?

Answer 29

VII lesser horn and upper body and IX greater horn/ lower body