Embryology Tutorial Quiz ll

Prof.Hishmat Haroon

Done By …

Met3eb Al.Otiby , Ahmed Al.Kjalefah , Baker Baha

and Abdullah Al.Zahrani

Directed By …

Ahmed Al.Mohsin

Batch

208

King Faisal University

College of medicine , Second Year

Batch 208

2

The Exam Will Include …

- 4 diagrams: 20 labels each diagram worth 5 marks

-10 fill in the blanks : 10 marks : give 2 examples of …

-10 T & F

-15 mcq

The Student Questions …

Q-name two bones of the 1st pharengeal arch ?

Q-name two muscles of the 1st pharengeal arch ?

Q-name two anomylies of the pancreas?

Q-name two developmental origins of the left atrium ?

A/ a.pulmonary venous bulge b.premitive fetal atrium c.left av canal

Q-name two developmental origins of the arch of aorta?

Q-name two developmental origins of right subcalvian artery ?

Q-name two developmental “thecal” viens constituting constituting

inf.venacava?

A/ a. right vitilline vien b.right subcardinal vien c, right supra cardinal vien

Q-drevatives of cranial part of forgut

Q-name two results of developmental rotation of the stomach ?

Q- laryngotracheal tube?

3

Q-components of falorix trunk?

Q-drevatives of dorsal mesogas? " هى بدال الدورسال قال كلمه هي اللي بتجي"

A/a.falciform ligamnit b.lesser omintum c.ventral mesogastrium

-Association with Tracheo-esophageal fistulas ((VACTERL)) …

1. Vertebral anomalies

2. anal atresia

3. Cardiac anomalies

4. tracheoesophageal fistula

5. Esophageal atresia

6. renal anomalies

7. Limb anomalies

-Congenital anomalies of the thyroid …

1\Congenital Absence

2\Ectopic Descends

3\Thyroglossal cyst

4\Thyroglossal fistula

-Derivatives of the floor of the pharynx.

-Anomalies of stomach –spleen and lung .

4

Diagrams …

1-development of sinus venosus :

-the doctor says every thing in the diagram.

2- Formation of inter atrial septum : a) ostium secondum

b) septum primum

c) septum intermedium

d) pulmonary vein

e) foramin ovalis

3- Fallot’s tetralogy :

1. Pulmonary stenosis

2. Hypertrophy of right ventricle

3. Interventricular septal defect

4. Overriding of the aorta

4- derivatives of aortic arches :

1. Common carotid

2. External carotid

3. Internal carotid

4. Subclavian artery

5. Arch of aorta

6. Ductus arteriosus

7. Pulmonary artery

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5- fetal circulation: “not common”

- but changes after birth are:

1. Ductus arteriosus obliterates and give legumentum arteriosum.

2. Umbilical vien obliterate and give legamentum teres of the liver.

3. Ductus venosus obliterate and give legamentum venosus.

6- ( 28:00 to 28 : 30 ) I couldn’t understand any thing.

7- pharyngeal pouches of pharyngeal cleft :

1. 1st cleft gives external auditory meatus

2. 2nd

, 3rd

& 4th gives the floor of cervical sinus

… and the rest you can find in the note almost the same…

Pharyngeal arches

First Arch: gives

Bones: Malleus, Incus and spine sphenoid

Muscles: - 4 Muscle of mastication (temporal; masseter; medial, lateral

pterygoids)

- Mylohyoid

- Anterior Belly of digastrics

- 2 Tensor muscles: Tympani and Palatine

Nerve Supply: Mandibular nerve

Second Arch ( Hyoid Arch ): gives rise

- Stapes bone

- Styloid process

- Half body of hyoid bone

- Lesser horn

- Stylohyoid ligment

Nerve Supply: Facial nerve

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► Muscles supplied by Facial Nerve: Muscle of Face, Muscle of scalp,

Posterior belly of digastrics, Stylohyiod muscle and muscle attached to stapes

called Stapedius.

Third Arch: gives one muscle only called stylopharyngeus muscle supplied

by Glossopharyngeal nerve.

Forth Arch: gives rise to cricothyroid muscle and one of Laryngeal cartilages

( Thyroid cartilage)

Sixth Arch:

All muscles of Larynx except cricothyroid muscle and all laryngeal

cartilages except Thyroid cartilage.

Nerve Supply: recurrent laryngeal nerve.

Tongue Development

Label pointed by the Dr. on the shown figure: Lingual swelling, Tuberculum

impar, Foramen cecum, Sulcus Terminalis and hypobranchial eminence.

► Tongue is endodermal and its derivative form first and third arch.

► Linguloalveolar groove appears separated from the floor of mouth

and if case of failure of separation its called

Tongue Tie or Ankyloglossia.

► Muscles of tongue arise from the occipital myotome.

Nervous supply of Tongue

Mucus membrane supplied by the 5th

(lingual N.),7th

(hypoglossal N.) and 9th

(Glossopharyngeal N.). on the other hand, the muscles are supplied by

Hypoglossal N.

Tongue Congenital Abnormalities

Macroglossia (كبير), Microglossia (صغير), Bifid tongue (مشقوق), Tie tongue

(غايب) Absent tongue ,(مربوط)

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Thyroid Gland Development

Label pointed by the Dr. on the shown figure: Inferior parathyroid, thymus

gland, superior parathyroid, thyroglossal duct, foramen cecum, thyroid gland.

► It develop between the Tuberculum impar and the hypobranchialeminence

in the floor of pharynx ???

On the Upper of thyroid isthmus.

After ??, will make a duct, duct will make a ??,?? contain some muscle fiber ??

Anomalies of thyroid gland:

- Anomalies of descent cause Ectopic Descends

- Anomalies of the duct cause Thyroglossal?? cyst located along the

mid-line and it moves up and

down with ??

- Abscent cause syndrome called Cretinism

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Development of respiratory tract

Laryngotracheal tube gives :

- Lower pat of Larynx - Trachea

Tube Branche to Right side gives 3 branches

and to Left side gives 2 branches ??

Anomalies of Lungs:

- Absent lung - Absent lobe - Accessory

lobe

- Less surfactant cause respiratory distress syndrome or hyaline

membrane disease or cystic lung

- Tracheoesophageal fistulas and Tracheoesophageal atresia and its

associated anomalies:

- Vertebral anomalies - Anal atresia - Cardiac

abnormalities

- Renal anomalies - Limb anomalies

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► Surfactant is phospholipid material an its function to reduce the high

tension in Air-blood interface, in cause it was Hypo in premature causes

respiratory distress or hyaline membrane disease.

Development of Stomach

► it rotates 90 degree to the Right

► Differential growth

- Greater Curvatures face to the left

- Lesser Curvatures face to the right

- Cavita?? behind the stomach called Omental Bursa.

► Derivatives of Ventral Mesogastrium

- Falciform ligment

- Lesser omentum

stomach

Congenital anomalies of the stomach :

1 ) Congenital hypertrophic pyloric stenosis .

2 ) abnormal rotation is the Transposition of the stomach .

( Rotate 90 degree to left instead to right )

3 ) Thoracic stomach :

Because of short Esophagus .

4) ectopic gastric mucosa ((( هذي النقطة مى مىجىدة في التفزيغ الزئيسي)))

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Spleen

- the main development of spleen is from mesenchymal condensation in the

middle of dorsal mesogastrium divide the middle part into gastrolenal

ligament & lenorenal ligament .

- the notches indicate the subdivision of the splenules .

What are the anomalies of the spleen ?

-1- cystic spleen .

-2- absent spleen .

-3- accessory spleens found in any peritoneum toward supernumeralspleens

( supernumeral means : more than the normal number )

Duodenum

The duodenum develops from the caudal part of the foregut and the

cephalic part of the midgut. It was connected by mesoduodenum .

the site of opening of hepatopencreatic empulla just below it and determine

The junction between the foregut and the midgut .

-Blood Supply of the Duodenum is an evidence :

(Foregut artery )- Superior Pancreatoduodenal artery coming from celiac artery.

(midgut artery )- Inferior Pancreatoduodenal artery from the superior

Mesenteric artery.

-Duodenal Atresia: due to failure Retention of the mesoduodenum and ectopic

gastric mucosa or ectopic pancreatic tissue .

Liver

The liver consists of parenchyma (glandular tissue) and connective (fibrous)

tissue capsule (stroma).

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- Its stalk make the common bile duct and it is divided into pars hepatica and

pars cystica .

- The pars cystica give raise to gallbladder and its stalk give raise to the cystic

duct.

- the stalk of pars hepatica gives common hepatic duct.

Pars hepatica as it grows it divides into right and left parts .

» The right part of pars hepatica gives the right lobe of the liver.

» The left part of pars hepatica gives the left lobe of the liver .

» Their (right and left part of pars hepatica) stalks give the right and left hepatic

ducts .

-- the liver of the fetus & newborn is relatively larger than of the adult liver .

» The capsule (stroma) of the liver is derived from the connective tissue of the

septum transversum or ventral mesogastrium .

» The vitelline and umbilical veins are broken down to form portal sinusoids,

portal vein and hepatic vein.

- What are The Anomalies of Biliary Passages ?

1) Biliary atresia .

2) Duplicated bladder .

3) Hartmann’s Pouch the major site of gallstone .

Pancreas …

It develops from two pancreases : ventral (smaller) and dorsal (larger)

pancreases .

The ventral pancreas is derived from the stalk of the liver bud while the dorsal

pancreas is derived from the concavity of the duodenal lobe.

» The dorsal pancreas gives the tail, body, neck and upper half of the head of

the pancreas.

» The ventral pancreas gives the lower half of the head and the uncinate

process of the pancreas.

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» The main pancreatic duct is derived from the distal part of the dorsal

pancreatic duct, the proximal part of the ventral pancreatic duct and an

anastamosis between the two ducts.

-Islets of Langerhans:

-They start to develop from the third month of development and secrete insulin

in the fifth month.

The Anomalies of Pancreas:

1- abnormal rotation of ventral pancreas anteriorly .

2- Annular Pancreas may compress the duodenum .

3- Ectopic Pancreatic Tissue .

Midgut …

- midgut has cephalic limb and caudal limb and vitelline duct

rotation 270 حصل لها -0 anticlockwise .

. herniation حصل لها -

( the most Important in the hereniation that is occur in 6th

week till the 9th

week

and begins at the 12th

week )

- the cephalic limb enter first then caudal limb and the last bud that enter is

cecal bud and become beneath the liver and then descend downwards !!!!!

47:10!!!! ascending colon .

-Colic flexure come from two different gut .

- right colic flexure come from mid gut .

- left colic flexure come from hind gut .

- the ileum comes from the two limb

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Most of ileum comes from cephalic limb and part of it come from caudal limb .

What are The anomalies of mid gut ?

- abnormalities of herniation : -- failure of completed !!!!!! gives omphocele

- abnormal rotation : if it is occurred so the transverse colon will become

behind the duodenum .

- failure to descend of the cecum this is called subhepatic cecum .

- failure to change postion of appendix this is called fetal appendix .

مهمة مهمة مهمة __ __ Anomalies of vitelline duct :

1- vitelline fistula .

2- failure of obliteration .

3- vitelline cyst

4- patents of the middle .

5- Meckels diverticulum .

-- occur in 2% of people and 2 inches long and 2 feet far away from ileocecal

junction and attached to ileum .

تن بحود اهلل تفيقه

في الختام اذكسكن فسي بالدعاء إلخاكن الريي عولا جاهديي على ايصال هرا التفسيغ في

، سائليي الولى عز جل لا لكن التفيق صزة افضل

، فسجا هكن أذكس باى هرا التفسيغ لن يتن هساجعته لضيق القت ظسف اإلختبازات

هساجعة تفازيغ الوحاضسات للتأكد هي الوعلهات أخر التفاصيل