Embryology Flashcards
Ectoderm gives rise to?
Skin. Oral Cavity. Nervous System.
Mesoderm gives rise to?
Muscles. Bones. Genitourinary System
Endoderm gives rise to?
Respiratory System. Gastrointestinal System
primitive oral cavity
stomodeum
separates the stomodeum from the foregut
buccopharyngeal membrane
fertilization period
implantation to 2nd week
embryonic period
2nd week to 8th week
fetal period
8th week to 36th week
pharyngeal arch 1
*M= mauuna
- meckel’s cartilage
- muscles of mastication
- CN V (trigeminal)
pharyngeal arch 2
*similar kay pharyngeal arch 1
- reichert’s cartilage
- muscles of facial expression
- CN VII (facial)
pharyngeal arch 3
* 3 = 3rd line…
- greater cornu of hyoid bone
- body of hyoid
pharyngeal arch 4
* 4ryngeal
- pharyngeal muscles
- laryngeal muscles & cartilages
pharyngeal arch 6
*larynX = siX
- laryngeal muscles
Neural tube
- brain
- spinal cord
pharyngeal pouch 1
*pouch = inner
- middle ear
- tympanic tube
- auditory tube
pharyngeal pouch 2
- palatine tonsil
- lymphatic nodule
pharyngeal pouch 3
*3 = three = t
- thymus
- inferior parathyroid gland
pharyngeal pouch 4
- superior parathyroid gland
- ultimobranchial body
pharyngeal cleft 1
- external auditory meatus
pharyngeal cleft 2 - 4
- cervical sinus
anterior 2/3rds of the tongue
- 1st pharyngeal arch (lateral lingual swelling) + tuberculum impar
posterior 1/3rd of the tongue
- 2nd and 3rd pharyngeal arch + copula
1st pharyngeal arch divides into…
- mandibular process
- maxillary process
- frontonasal process
Mandibular process
- lower face
- lower lip
- mandible
Maxillary process
- mid face
- cheeks
- upper lip sides
- maxilla
- secondary palate (palatine process)
Frontonasal process
- lateral nasal process
- medial nasal process
Lateral nasal process
* nasa side (lateral)
- ala of the nose
- infraorbital area
Medial nasal process
* nasa gitna (medial)
- bridge and tip of the nose
- medial nasal septum
- globular process
- intermaxillary segment
Globular process
- philtrum
- center of upper lip
Intermaxillary segment
- primary palate
Thyroid duct…
- Tuberculum impar + Copula
Oral Vestibule
- Vestibular lamina
remnant of thyroid duct
foramen cecum
found at terminal sulcus
non fusion of lateral lingual swellings of pharyngeal arch 1
bifid tongue
becomes nostrils
olfactory placodes
failure of maxillary process to fuse with the medial nasal process on both sides
bilateral cleft lip
failure of maxillary process to fuse with the medial nasal process on affected side
unilateral cleft lip
hard palate cleft
uranoschisis
soft palate cleft
staphyloschisis
both hard and soft palate involved
uranostaphyloschisis
BEQ: maxillary teeth are developed from which of the following embryonic structures?
pharyngeal arch 1 & globular process
BEQ: neural tube formation happens when?
2nd stage of neurulation, 18th to 23rd day post fertilization
Adult: Ligamentum arteriosum (Arteriosum=A=artery)
Fetal?
Associated structures?
Fetal: Ductus arteriosus
Assoc. structures: aorta, pulmonary artery
Adult: Ligamentum venosus (Venosum=V=vein)
Fetal?
Associated structures?
Fetal: Ductus venosus
Assoc. structures: umbilical vein, inferior vena cava
Adult: Foramen ovale
Fetal?
Associated structures?
Fetal: Fossa ovalis
Assoc. structures: right atrium, left atrium (bypass pulmocirculation)
Adult: Ligamentum teres of the liver, medial umbilical ligaments
Fetal?
Fetal: Umbilical vein and arteries
1st week of prenatal development
ZYGOTE -> cleaves -> BLASTOMERE -> 32 cells -> MORULA
2nd week of prenatal development
*morula -> trophoblast, embryoblast, blastocoele disintegration of zona pellucida -> BLASTOCYST -> +endoderm, ectoderm
3rd week of prenatal development
> bilaminar germ disk: - ectoderm with primitive streak - endoderm > trilaminar germ disk: - + mesoderm > neurulation: - notocord on mesoderm - neural plate on ectoderm - neural plate = neural fold - notocord = neural tube - neural tube = neural crest cells - neural groove
4th week of prenatal development
infoldings appear
- head, tail, lateral folds
5th week of prenatal development
olfactory placodes -> nostrils
eyes become more prominent
6th week of prenatal development
Frontonasal process splits into:
- medial nasal process
- globular process
- intermaxillary segment
- lateral nasal process
Eyes move infront
Ears move to side of the head
Vestibular lamina formation
Odontogenesis