development

Question 1

how many pairs of cranial nerves are there

Answer 1

12

Question 2

name the cranial nerves

Answer 2

olfactory
optic
occulomotor
trochlear
tigeminal
abducent
facial
vestibulo-cochlear
glosso-pharyngeal
vagus
accessory
hypo-glossal

Question 3

what does the cavitation of the mesoderm in the trunk result in

Answer 3

splanchnic and somatic lateral plate mesoderm enclosing a coelomic cavity

Question 4

development of mesoderm in the head

Answer 4

cavitation does not occur in the head
lateral plate mesoderm remains as a solid belt of tissue surrounding gut tube
intermediate mesoderm fails to develop

Question 5

how many segments in the head

Answer 5

7

Question 6

what do head segments contain

Answer 6

ectoderm
somites
endoderm
lateral place mesoderm
segmental arteries
neuraxis
nerves

Question 7

what does the ectoderm form

Answer 7

outer epithelial covering = skin

Question 8

function of ectoderm

Answer 8

somatic sensation eg touch, pressure, temperature, pain

Question 9

what is the ectoderm innervated by

Answer 9

somatic afferents

Question 10

what are segments marked externally by

Answer 10

lateral indentations

Question 11

what does ectoderm segments 1 and 2 form

Answer 11

stomodeum = oral opening

Question 12

what is the oral plate

Answer 12

thin plate of tissue where stomodeal ectoderm meets pharyngeal endoderm

Question 13

what does the endoderm form

Answer 13

inner epithelial covering

Question 14

what is the sensation of the endoderm supplied bt

Answer 14

autonomic afferents

Question 15

what does the cephalic part of the fore-gut become

Answer 15

pharynx

Question 16

how many divisions is the endoderm marked off into and by what

Answer 16

6 by 6 gill slits

Question 17

what are gill slits referred to in mammals

Answer 17

pharyngeal pouches

Question 18

what do pharyngeal pouches perforate into in fish

Answer 18

external gill slits

Question 19

what is the lateral plate mesoderm

Answer 19

belt of striated skeletal muscle that surrounds pharynx of all segments except segment 1

Question 20

what does each belt of lateral plate mesoderm form and what are they separated by

Answer 20

a donut’
separated by pharyngeal cleft externally and the pharyngeal pouch internally

Question 21

what is each belt referred to in lateral plate mesoderm

Answer 21

pharyngeal arch

Question 22

what does lateral plate mesoderm form

Answer 22

special visceral muscle of the gut tube

Question 23

what is lateral plate mesoderm innervated by

Answer 23

special visceral efferents

Question 24

what do somites form

Answer 24

striated muscle of eyeball and tongue

Question 25

innervation of somites

Answer 25

somatic efferents

Question 26

what do segmental arteries form

Answer 26

6 pairs of aortic arches

Question 27

what are segmental arteries innervated by

Answer 27

autonomic afferents/efferents