General Anatomy

Question 1

What are the three germinal layers?

Answer 1

Endoderm
Mesoderm
Ectoderm

Question 2

What are the four parts of mesoderm?

Answer 2

1. Paraxial
2. Intermediate
3. Head
4. Lateral plate

Question 3

What does the paraxial mesoderm give rise to?

Answer 3

Somites (31 pairs)

Question 4

What does the intermediate mesoderm create?

Answer 4

Urogenital system and KIDNEYS

Question 5

What does the head mesoderm create?

Answer 5

Skull
Muscles
Connective tissue of the head
Dentine

Question 6

What arises from the lateral plate mesoderm?

Answer 6

ADRENAL CORTEX, SPLEEN, blood and lymph cells, connective tissue, cardiovascular and lymphatics, serous membranes of pleura and pericardium.

Question 7

What does the endoderm give rise to?

Answer 7

Gut
Respiratory tract
“Tubular structures”

Question 8

What does ectoderm give rise to?

Answer 8

Surface ectoderm

Neuroectoderm

Question 9

What does the surface ectoderm form?

Answer 9

Epidermis, enamel, hair, nails

ANTERIOR PITUITARY
LENS OF EYE

Question 10

What makes up the neuroectoderm?

Answer 10

Neural tube

Neural crest

Question 11

What are the structures derived from the neural tube?

Answer 11

CNS
POSTERIOR PITUITARY
RETINA OF EYE
pineal body

Question 12

Which structures are derived from neural crest cells?

Answer 12

Dorsal Root Ganglion (DRG)
ANS
Parafollicular cells of thyroid
Adrenal Medulla

Question 13

What are the embryological stages of development?

Answer 13

Mesodermal -> Chondrification -> Ossification

Question 14

What makes up the major two parts of mesodermal embryological development?

Answer 14

1. Notochord persists as nucleus pulposus

2. 31 pairs of mesodermal somites from paraxial mesoderm

Question 15

What are the types of paraxial mesoderm?

Answer 15

Sclerotome
Myotome
Dermatome

Question 16

What is sclerotome?

Answer 16

The membranous vertebral column formed during paraxial mesodermal embryological development.

Question 17

What is myotome, and what are the myotomes?

Answer 17

Myotome = Muscle

1. Somatic
2. Splanchnic
3. EPIMERE
4. HYPOMERE

Question 18

What does somatic myotome become?

Answer 18

Skeletal muscle

Question 19

What does splanchnic myotome become?

Answer 19

“Visceral” smooth muscle

Question 20

What is derived from the EPIMERE myotome?

Answer 20

Dorsal, Posterior muscles, Extensors

Question 21

What does the HYPOMERE myotome become?

Answer 21

Ventral, anterior muscles, flexors

Question 22

What is chondrification?

Answer 22

Mesoderm being replaced by cartilage.

Question 23

What is ossification?

Answer 23

Cartilage being replaced by bone.

Question 24

What are the two types of ossification?

Answer 24

Primary ossification = before birth

Secondary ossification = after birth

Question 25

What happens during intramembranous/intramedullary ossification?

Answer 25

Mesenchymal tissue turns into bone

The clavicle and all flat bones of the skull are formed (e.g. parietal).

Question 26

What happens during endochondral ossification?

Answer 26

Preformed in cartilage

Ossification for all other bones

Question 27

What type of ossification leads to the creation of the scapula?

Answer 27

Intramembranous and Endochondral