Dh-Ohe: Deha Ch 4-Development Of The Face And Neck

Front 1

When does the face begin to form, and when is it completed?

Back 1

Development of the Face

(1) Begins-4th wk of embryonic period
(2) Completes-12th wk of FETAL period
(3) FACE Squeezed b/w dev. brain & heart

Hint 1

DEHA Ch 4, p.40

Front 2

What layers of the embryo are involved in facial development?

Back 2

Facial Development:

DEPENDS ON:
all THREE embryonic layers

(1) Ectoderm (2) Mesoderm (3) Endoderm

Hint 2

DEHA Ch 4, p.40

Front 3

Facial Development depends on what processes?

Back 3

Facial Development

Depends on (5) facial processes (aka "prominences)

(1) Single Frontonasal Process
(2) Paired Max. Processes
(3) Paired Mand. Processes

Hint 3

DEHA Ch 4, p.40; Powerpoint

Front 4

The five facial processes represent centers of growth. What do they correspond to on the face?

Back 4

Five Facial Processes---and the face

(1) Frontonasal process = upper 1/3
(2) Max. processes = middle 1/3
(3) Mand. processes = lower 1/3

Hint 4

DEHA Ch 4, p.40; Powerpoint

Front 5

What is the term for the primitive mouth? What is its lining? When does it form?

Back 5

Oral Cavity Formation

Primitive Mouth = STOMODEUM
FORMS: during 3rd week
LINING: Ectoderm (future oral epithelium)

Hint 5

DEHA Ch 4, p.41; Powerpoint

Front 6

What purpose does the Oropharyngeal Membrane serve?

Back 6

Oropharyngeal Membrane

PURPOSE: Separates the stomdeum (mouth) from the primitive pharynx (3rd week)

Hint 6

DEHA Ch 3,p. 41

Front 7

What occurs during the 4th week in the Oral Cavity formation? What is it's significance?

Back 7

Oral Cavity Formation: (4th week)

(1) The Oropharyngeal Membrane disintegrates

SIGNIFICANCE: Allowing primitive mouth to INCREASE in depth

Hint 7

DEHA Ch 3, p.41

Front 8

What is the primitive pharynx?

Back 8

Primitive Pharynx:

(1) cranial portion of the FOREGUT
(2) beginning of future DIGESTIVE tract

Hint 8

DEHA Ch 3, p.41

Front 9

What are the mandibular processes, and how do they form portions of the lower face?

Back 9

MANDIBULAR PROCESSES:
The (2) bulges of tissue INFERIOR to the primitive mouth

Lower Face Formation:
Mand. processes + Neural crest cells FUSE Forms:
(1) Mand. Arch (2) Lower Lip

Hint 9

DEHA Ch 3, p.42

Front 10

What is the first branchial arch and Meckel’s cartilage?

Back 10

1st BRANCHIAL ARCH =Mand. Arch

Meckel's cartilage:
(1) forms on each side of 1st arch
(2) later disappears w/formation of bony mandible

Hint 10

DEHA Ch 3, p.42

Front 11

What is the frontonasal process? To what portions of the face does it give rise?

Back 11

Frontalonasal Process:

single bulge cephalic end of embryo

FORMS
(1) UPPER FACE
(2) forehead
(3) primary palate
(4) Nose (Medial, Lateral nasal processes)

Hint 11

DEHA Ch 4, p.44

Front 12

Define placodes

Back 12

Frontonasal Process

PLACODES:
Rounded proliferations on the frontonasal process that develop into special sense organs

Hint 12

DEHA Ch 4, p.44

Front 13

Describe the location of the lens, otic, and nasal placodes and what do they form

Back 13

PLACODES

Lens placodes- each side laterally, migrate medially FORMS EYES

Otic placodes-each side far laterally FORMS INTERNAL EAR

Nasal placodes-sup. stomodeum FORMS OLFACTORY CELLS

Hint 13

DEHA Ch 4, p.44

Front 14

Describe the further development of the nasal placodes and their relationship to the oronasal membrane.

Back 14

NOSE DEVELOPMENT:
Nasal placodes -->NASAL PITS--> Nasal Cavities--> Nasal Sacs

Nasal Sacs are separated from stomodeum by ORONASAL MEMBRANE (later disintegrates brings nasal & oral cavities in communication)

Hint 14

DEHA Ch 4, p.44

Front 15

Describe the medial and lateral nasal processes on an embryo what they form with fusion.

Back 15

MEDIAL PROCESSES
2 crescent shaped swellings b/w nasal pits.
Fusion of both = center of upper lip

LATERAL NASAL PROCESSES:
2 crescent shaped swellings outer portion of nasal pits.
Fusion of both = Alea of Nose

Hint 15

DEHA Ch 4, p.44

Front 16

What is the intermaxillary segment? To what does it give rise?

Back 16

Inter = "inside" Maxillary ="upper arch"

INTERMAXILLARY SEGMENT:
forms from the INTERNAL fusion of the MEDIAL NASAL processes

FORMS:
(1) max. incisor teeth (2) primary palate (3) nasal septum

Hint 16

DEHA Ch 4, p.44

Front 17

What happens to the mandibular arch during the fourth week. To what does this new process give rise?

Back 17

With overgrowth of the Mandibular Arch it gives rise to the Maxillary Process

WHICH FORMS:
(1) Middle of face
(2) sides of the upper lip (3) cheeks
(4) secondary palate (5) post. maxilla (6) zygoma (7) temporal bone

Hint 17

DEHA Ch 4, p.44

Front 18

Describe the embryological development of the upper lip.

Back 18

UPPER LIP FORMATION:

(1) SIDES OF UPPER LIP: forms from Max. Process

(2) MIDDLE OF UPPER LIP: forms from Medial nasal process

(3) COMMISSURES: fusion of Max & Mand. processes

Hint 18

DEHA Ch 4, p.46

Front 19

What occurs with failure of fusion during the development of the upper lip, and what are its ramifications orally?

Back 19

FAILURE OF FUSION (UPPER LIP)

Cleft Lip - when max & medial processes fail to fuse
(1) inherited or acquired
(2) Unilateral or bilateral
(3) With or w/o cleft palate

Ramifications: complicates nursing/feeding of child, speech dev, appearance, oronasal infections

Hint 19

DEHA Ch 4, p.46

Front 20

How does the primitive pharynx develop? What does the cephalic and caudal parts become?

Back 20

PRIMITIVE PHARYNX
Develops: from anterior FOREGUT
Origin: Endoderm layer

Cephalic end = oropharynx
Caudal end = esophagus

Hint 20

DEHA Ch 4, p.47

Front 21

What is the branchial apparatus?

Back 21

BRANCHIAL = "gills" for resp. function (aka "pharyngeal" humans)

Branchial Apparatus includes:
(1) Branchial ARCHES
(2) Branchial GROOVES
(3) Branchial POUCHES

Hint 21

DEHA Ch 4. p 47

Front 22

To which tissues does each branchial arch give rise?

Back 22

BRANCHIAL ARCHES

1st arch (Mand. Process)
-middle & lower face(maxilla, mand)

STRUCTURES of the NECK
2nd arch (Hyoid Arch)
-part of the hyoid bone
3rd arch
-remainder of hyoid bone
4th-6h arches
-laryngeal cartilages

Hint 22

DEHA Ch 4. (p 47-48)
Table 4.2 (p 43)

Front 23

What are the branchial grooves? What does the 1st groove form?

Back 23

BRANCHIAL GROOVES

LOCATED: on outside of embryo b/w the arches

1st Groove: external auditory meatus (eardrum)

Hint 23

DEHA Ch 4. p 49

Front 24

Name the tissues associated with each pharyngeal pouch.

Back 24

Branchial (Pharyngeal) Pouches:

LOCATED: on INSIDE pharynx b/w the arches

1st Pouches-forms EAR CANAL

2nd Pouches-PALATINE TONSILS

3rd/4th Pouches- Parathyroid, Thymus glands (processes key lymphocytes)

Hint 24

DEHA Ch 4. p 49

Front 25

What are cervical cysts, and how can they present?

Back 25

CERVICAL CYSTS:

Form when branchial grooves do not obliterate

(1) Can drain through sinuses along neck
(2) slowly enlarging, painless swelling

Hint 25

DEHA Ch 4. p 49