Anatomy 6511 Germ Layer Derivities and Body folding Embryology 낱말 카드

Ectoderm

Which germ layer gives rise to the CNS and PNS?

Ectoderm

Which germ layer gives rise to the epidermis?

Ectoderm

Which germ layer gives rise to nails and hair?

Ectoderm

Which germ layer gives rise to sensory epithelium of the ears, nose and eyes?

Ectoderm

Which germ layer gives rise to sweat, sebaceous, lacrimal and mammary glands?

Ectoderm

Which germ layer gives rise to tooth enamel?

Ectoderm

Which germ layer gives rise to the pituitary gland?

Ectoderm

Which germ layer gives rise to the external auditory meatus?

Between 3rd and 4th week

When does neurulation occur?

Formation of the neural tube

What is neurulation?

Ectoderm

What germ layer does neurulation take place?

Brain and spinal cord (CNS)

Which does the neural tube give rise to?

Dorsal aspect of the neural tube

Where are neural crest cells located?

Ventrally into underlying mesoderm

Where do neural crest cells migrate to?

Majority of PNS structures

(Noteable: Septum of heart, dorsal root ganglia, bones/dermis of face)

What do neural crest cells give rise to?

Paraxial mesoderm

The mesoderm initially thickens along the midline of the embryo to form what?

Lateral plate mesoderm

Laterally the mesoderm remains thin to form what?

Somatic (parietal) and splanchnic (visceral) mesoderm

The lateral place mesoderm divides into what two layers?

Intermediate mesoderm

What is located between the paraxial mesoderm and the lateral plate mesoderm?

Paraxial mesoderm

(located on either side of notochord)

Which part of the mesoderm would be labelled in the orange box?

Intermediate mesoderm

Which part of the mesoderm would be labelled in the orange box?

Somites

At the third week, paraxial mesoderm begins to organize into ball like segments called what?

Formation of axial skeleton

What is the function of somites?

Paraxial mesoderm

Which part of the mesoderm are somites found?

Occipital region

The first pair of somites arise in what region of the embryo?

False

(Cranial to caudal)

True or False: Somite development progresses caudal to cranial.

42-44

At the end of the fifth week, how many pairs of somites are present?

4

How many pairs of somites are present in the occipital region?

8

(same as # of cervical nerves)

How many pairs of somites are present in the cervical region?

12

(same as # of thoracic nerves)

How many pairs of somites are present in the thoracic region?

5

(same as # of lumbar nerves)

How many pairs of somites are present in the lumbar region?

5

(same as # of sacral nerves)

How many pairs of somites are present in the sacral region?

8-10

How many somites are present in the coccygeal region?

1st occipital somite and some coccygeal somites

Which somites regress?

Axial skeleton

The rest of the somites form what?

Epithelization

Somites undergo what to form a donut like structure?

Sclerotome

Ventral and medial somitic cell sbecome mesenchyme to form what? (Labelled by blue box)

Dermatome

Cells between dorsomedial and ventrolateral somitic cells form what? (Labelled by gray box)

Muscle cells

Cells at dorsomedial and ventrolateral edges of somites form precursors for what cells?

Myotome

Cells will become mesenchymal and migrate beneath dermatome and form what? (Labelled by yellow box)

Vertebrae and ribs

(sclera=bone)

What does the sclerotome give rise to?

Dermis of dorsal body region

(derma=skin)

What does the dermatome give rise to?

Trunk and limb musculature

(myo=muscle)

What does the myotome give rise to?

Urogenital structures

(kidneys, ureter, female/male reproductive anatomy)

The intermediate mesoderm gives rise to which structures?

Somatic (parietal) layer and splanchnic (visceral) layer

The lateral plate mesoderm splits into what two layers?

Amniotic cavity

Which cavity is lined by the somatic/parietal lateral plate mesoderm?

Yolk sac

Which cavity is lined by the splanchnic/visceral lateral plate mesoderm?

Somatic

(think outside)

Does the somatic or splanchnic lateral plate mesoderm give rise to the dermis of the ventral body region?

Somatic

Does the somatic or splanchnic lateral plate mesoderm give rise to bones and ligaments?

Somatic (parietal)

Does the somatic or splanchnic lateral plate mesoderm give rise to parietal serosa?

Splanchnic

Does the somatic or splanchnic lateral plate mesoderm give rise to walls of the digestive and respiratory tracts?

Splanchnic

Does the somatic or splanchnic lateral plate mesoderm give rise to the heart and blood vessels?

Splanchnic (visceral)

Does the somatic or splanchnic lateral plate mesoderm give rise to visceral serosa?

Paraxial mesoderm

What is labeled 1?

Amniotic cavity

What is labeled 2?

Intermediate mesoderm

What is labeled 3?

Somatic lateral plate mesoderm

What is labeled 4?

Splanchnic lateral plate mesoderm

What is labeled 5?

Yolk sac

What is labeled 6?

Ectoderm and somatic mesoderm

Which germ layers form the lateral body wall?

Splanchnic mesoderm and endoderm

Which germ layers form the wall of the gut tube?

Somatic and splanchnic mesoderm layers

The intraembryonic cavity is located between what two layers?

Abdominal cavity

What does the intraembryonic cavity give rise to eventually?

Vasculogenesis

Blood vessels arise from blood islands

Angiogenesis

New blood vessels sprout from existing vessels

Splanchnic lateral plate mesoderm

Blood cells and vessels arise from what layer?

Wall of yolk sac

The first blood cells arise in blood islands surrounding what structure?

Mesoderm surrounding the aorta

The definitive hematopoietic stem cells are derived from what?

Liver

The definitive hematopoietic stem cells colonize what organ?

Liver

What is the major hematopoietic organ of an embryo?

Bone marrow

Stem cells from the liver colonize what?

Blood forming function

Stem cells from the liver colonize the bone marrow and the liver loses what function?

7th month

During what month of gestation does the liver lose its blood forming function?

True (later becomes nucleus pulposus)

True or False: The notochord is only present during early embryonic development.

Nucleus pulposus

What structure is remnant of the notochord?

Nucleus pulposus

What structure is labelled?

Endoderm

Which germ layer gives rise to epithelial linings?

Endoderm

Which germ layer gives rise to the parenchyma of the thyroid, parathyroid, liver and pancreas?

Primitive streak

What establishes the body axes of the embryo?

True

True or False: Body folding occurs simultaneously in sagittal and lateral planes.

Ventral body wall

During neurulation (week 3), right and left sides of the embryonic disc flex and move ventrally to close what?

Vitelline duct

What term describes the remaining connection between the midgut and yolk sac during lateral body folding?

Ventral body wall and primitive body cavity

Lateral body wall folds meet in midline forming what?

Primitive gut tube

The splanchnic mesoderm and endoderm form what during lateral body folding?

Vitelline duct

What is labelled 1?

Primitive gut cavity

What is labelled 2?

The development of the brain

(increased weight causes cranial end to curve ventrally)

What causes cranial folding?

Oropharyngeal membrane

Which structure acts as a hinge during cranial body folding to correctly orient the brain, mouth, heart, and diaphragm?

Mouth

What does the oropharyngeal membrane give rise to?

Diaphragm and connective tissue of liver

What does the septum transversum give rise to?

Septum transversum

Which structure separates the primitive thoracic and abdominal cavities?

Growth of the distal neural tube

What causes caudal folding?

Cloacal membrane

Which structure swings ventrally during caudal body folding to correctly orient the umbilical cord/connecting stalk, urogenital, and anal openings?

Connecting stalk

What becomes the future umbilical cord is now attached to the ventral aspect of embryo?

Septum transversum

Block of splanchnic mesoderm that forms connective tissue of liver and central tendon of diaphragm

Primitive thoracic and abdominal

The septum transversum separates what cavities?

Pleuropericardial folds

Which structure expands to form a definitive wall between the thorax and pleuropericardial membranes?

Pleuropericardial membranes

Which structure forms definitive pleural and pericardial cavities?

Pleuropericardial membranes

Which structure contains the phrenic nerve?

Pericardioperitoneal canals

What structure connects the pleural cavities to the peritoneal cavity by travelling through the septum transversum?