Development Of Digestive And Respiratory System

Question 1

The lining of the digestive system:

a) is mainly a derivative of the entodermal germ layer
b) the ectoderm participates in its formation
c) has no contribution from the ectomesenchyme that is of the neural crest origin
d) the lining epithelium of the yolk sac participates in its formation

Answer 1

A,b,d

Question 2

Which statements are correct?

a) on approximately the 16th day of the embryonic development, the embryo begins
to fold ventrally

b) due to the expansion of the amniotic sac, a piece of the yolk sac becomes the
primitive gut

c) the yolk sac remains connected to the primitive gut tube via the vitelline duct
d) the vitelline duct persists on to adult life to form the pharynx

Answer 2

A,b,c

Question 3

Vitelline duct:

a) is also called ductus omphaloentericus

b) connects the yolk sac and the primitive gut during some period of the develop-
ment

c) can persist and form the Meckel’s diverticulum
d) forms the small and large intestine

Answer 3

A,b,c

Question 4

Which statements are correct about the primitive gut?

a) is of endodermal origin
b) it can be called also archenteron
c) remains connected with the yolk vesicle by the yolk stalk
d) it is of ectodermal origin

Answer 4

A,b,c

Question 5

The yolk stalk:

a) is the outgrowth from the primitive node that contributes to the formation of
notochord

b) connects the primitive gut with the rest of the yolk vesicle
c) becomes reduced later in a very narrow duct called the ductus omphaloentericus
d) is lined by mesoderm

Answer 5

B,c

Question 6

The primitive gut:

a) is opened in the cranial end into the prosencephalon
b) is closed only caudally by an oropharyngeal membrane
c) is of endodermal origin
d) is a blind tube that is closed on both (cranial and caudal) sides

Answer 6

C,d

Question 7

The oral (oropharyngeal) membrane:

a) is situated in the region of prechordal plate
b) temporary closes the primitive gut in the cranial region

c) consists of the cells of ectoderm and entoderm, which are in closest contact and
fuse completely

d) closes the primitive gut also in the caudal region

Answer 7

A,b,c

Question 8

The oral (oropharyngeal) membrane:

a) is situated in the region of prechordal plate
b) breaks down within the 3rd week of development
c) consists of mesenchyme
d) contributes to the development of mesonephros

Answer 8

A,b

Question 9

Stomodeum:

a) is a part of yolk sac
b) leans on the oral membrane
c) is of ectodermal origin
d) becomes part of the primitive pharynx

Answer 9

B,c,d

Question 10

Stomodeum:

a) is a part of expanded amniotic sac
b) leans on the cloacal membrane
c) is of endodermal origin
d) becomes part of the primitive pharynx

Answer 10

A,d

Question 11

Which statements are correct about the primitive pharynx:

a) the pharyngeal cavity starts to evaginate on its lateral sides into pharyngeal
(visceral or branchial) pouches

b) branchial clefts originate to form the amniotic ectoderm
c) the first arch becomes early rudimentary and soon disappears completely
d) the fifth arch protrudes in the region of stomodeum

Answer 11

A,b

Question 12

Which statements are correct about the pharyngeal clefts?

a) they are lined by ectoderm
b) they represent the future neck region
c) from all four clefts, the first cleft persists postnatally only
d) they form the most inner part of the pharyngeal complex

Answer 12

A,b,c

Question 13

The ectoderm of pharyngeal clefts:

a) contributes to the primitive gut lining
b) thickens in epibranchial neuroplacodes
c) can proliferate in neuroblasts
d) contributes to the neural structures of the corresponding pharyngeal arches

Answer 13

B,c,d

Question 14

Which statement is correct about the pharyngeal clefts?

a) the second, third and fourth pharyngeal clefts form the cervical sinus
b) they are lined by endoderm
c) all contribute to the primitive gut lining
d) they disappear at the second week of the embryonic development

Answer 14

A

Question 15

Cervical sinus:

a) is formed by the fifth and sixth pharyngeal clefts
b) becomes closed by an operculum

c) becomes closed by a mesenchymal cover that is growing out from the second
(hyoid) arch

d) its remnants can persist to form the branchiogenic neck cysts

Answer 15

B,c,d

Question 16

The first pharyngeal pouch:

a) forms the basis for the development of the outer ear
b) form the cervical sinus
c) forms the basis for tubo-tympanic cavity of the middle ear

d) deepens and the entodermal lining of its bottom touches the ectodermal epithe-
lium of the first cleft

Answer 16

C,d

Question 17

Which statements are correct about the second pharyngeal pouch?

a) its branchial membrane usually breaks down
b) the pouch opens at least temporary into the corresponding cleft and in that case a continuous channel develops
c) contributes to tonsillar crypts development
d) contributes to the cervical sinus development

Answer 17

A,b,c

Question 18

The third pharyngeal pouch:

a) contributes to the primordium of the inferior parathyroid
b) forms the primordium of the thymus
c) forms the basis for the development of the outer ear
d) forms the basis for tubo-tympanic cavity of the middle ear

Answer 18

A,b

Question 19

The fourth pharyngeal pouch:

a) is more spacious pouch than the others

b) consists of the joined fourth and fifth pouches, between which the fifth branchial
arch disappeared

c) part of its epithelium proliferates into the primordium of the upper pair of
parathyroids

d) forms the basis for the development of the outer ear

Answer 19

A,b,c

Question 20

The distal part of the fourth pouch:

a) represents in fact the reduced fifth pouch
b) develops into the thymus
c) develops in ultimobranchial body
d) differentiate in parafollicular cells of the thyroid gland

Answer 20

A,c,d

Question 21

Which statements are correct about the pharyngeal arches?

a) they are formed as ventrolateral structures among the proper pouches and clefts
b) the first arch is called the mandibular arch
c) the second arch is called hyoid arch
d) the first arch disappears

Answer 21

A,b,c

Question 22

Which statements are correct about the pharyngeal arches?

a) they are build from young connective tissue, mostly of ectomesenchymal origin
b) they contain no vessels and no nerves
c) they are covered, at least in parts, by ectodermal epithelium
d) every arch differentiates in a relevant skeleton and muscles

Answer 22

A,c,d

Question 23

The first (mandibular) arch:

a) forms the upper part of the hyoid skeleton
b) contributes to the development of Meckel’s cartilage
c) forms the lower part of the hyoid body
d) forms thyroid and cuneiform cartilages

Answer 23

B

Question 24

The second (hyoid) arch:

a) forms the thyroid and cuneiform cartilages
b) forms the upper part of the hyoid skeleton
c) the muscle primordials form the muscles of facial expression
d) forms the lower part of the hyoid body

Answer 24

B,c

Question 25

The chondroblastema of the third pharyngeal arch: a) completes the skeleton of the second arch b) forms the lower part of the hyoid body c) forms the thyroid and cuneiform cartilages d) forms the upper part of the hyoid skeleton

Answer 25

A,b

Question 26

The artery of the first pharyngeal arch: a) disappears very early b) its remnant form the maxillary artery c) forms the carotid complex d) forms the pulmonary artery

Answer 26

A,b

Question 27

The artery of the second pharyngeal arch: a) disappears very early b) its remnant forms the stapedial artery c) forms the carotid complex d) forms the pulmonary artery

Answer 27

A,b

Question 28

Which statements are correct about the pharyngeal arches? a) the second arch is vascularized by the carotid complex b) the fourth arch is supplied by the aortic complex c) the first arch is supplied on the right side by the subclavian artery d) the fifth pharyngeal arch is a rudimentary one and degenerates

Answer 28

B,d

Question 29

Which statements are correct about the pharyngeal arches? a) the third arch is vascularized by the carotid complex b) the first arch is supplied by the aortic complex c) the fourth arch is supplied on the right side by the subclavian artery d) the sixth arch contains the represented by the pulmonary artery

Answer 29

A,c,d

Question 30

The pharyngeal arches are innervated by the cranial nerves: a) V. b) VII. c) IX. d) XI.

Answer 30

A,b,c

Question 31

Ganglia of cranial nerves originate: a) partially from cells of the neural crest b) partially from endodermal lining of the primitive gut c) partially from the neuroectoderm of epibranchial neurogenic placodes d) partially from the endoderm of ductus omphaloentericus

Answer 31

A,c

Question 32

The tongue: a) partially originates in pure ectodermal region of the stomodeum b) partially comes from the entodermal copula c) develops from Rathke’s pouch d) develops during the second week of the embryonic development

Answer 32

A,b

Question 33

The development of the thyroid gland: a) starts in the third week of the embryonic development b) starts just behind the oro-pharyngeal membrane c) can result in accessory cysts in the midline of the neck d) starts from the neuroectoderm

Answer 33

A,b,c

Question 34

The thyreoglossal duct: a) should become interrupted during the thyroid gland development b) its remaining upper part may persist as a blind pit on the tongue as the foramen caecum c) some of its cells can result in so called accessory thyroids on the way of its descent d) forms the pituitary gland

Answer 34

A,b,c

Question 35

The stomodeum: a) has been developed during folding of the embryo and expanding of the amniotic sac against the yolk vesicle b) is lined by ectoderm c) its stomodeal cavity is situated in the region of the first branchial arch d) is lined by mesenchyme

Answer 35

A,b,c

Question 36

The development of the pituitary gland: a) starts just in front of the oro-pharyngeal membrane in the roof of stomodeum b) starts with a small pouch called Rathke’s pouch c) has no ectodermal contribution d) has no contribution from the diencephalon

Answer 36

A,b

Question 37

Which statements are correct about the pituitary gland development? a) the infundibular diencephalic recess grows down against the Rathke’s pouch b) the stem of Rathke’s pouch disappears c) the development of the pituitary gland is completed at the second week of the embryonic development d) the pituitary gland is of pure entodermal origin

Answer 37

A,b

Question 38

The pharyngeal tonsils: a) develop as originally paired lymphatic structures in the vault of the nasopharynx b) develop from Rathke’s pouch c) develop at the second week of the embryonic development d) develop from the thyreoglossal duct

Answer 38

A

Question 39

The yolk stalk: a) undergoes complete obliteration during the 7th week of the embryonic develop- ment b) in about 2% of cases its proximal part persists as Meckel’s diverticulum c) persists and forms the thyreoglossal duct d) develop into Rathke’s pouch

Answer 39

A,b

Question 40

Meckel’s diverticulum: a) is a diverticulum from the small intestine b) it is situated about 60 cm proximal to the ileocecal valve c) it may be attached by a fibrous cord to the abdominal wall at the umbilicus d) it not clinically important because it always regresses before birth

Answer 40

A,b,c

Question 41

Which statements are correct about teeth development? a) the primary teeth start to form between the 6th and 8 th week of the embryonic development b) permanent teeth begin to form in the 10–12 th week of prenatal development c) teeth starts to develop from the labio-gingival groove d) teeth development has no ectodermal contribution

Answer 41

A,b,c

Question 42

Teeth development: a) starts from the labio-gingival lamina b) comprises the dental lamina that connects the developing tooth bud to the epithelial layer of the mouth c) ends before child birth d) ends with the crown stage

Answer 42

A,b,d

Question 43

Development of the teeth: a) starts during the 6th month of prenatal development b) starts as a thickening of the oral ectodermal epithelium c) ends with the crown stage of the permanent teeth d) is completed before the age of three years

Answer 43

B,c

Question 44

The labio-gingival groove: a) separates the lip from the gum b) starts as a thickening of the oral ectodermal epithelium c) its epithelium proliferates into the gingival mesenchyme forming the teeth buds d) is of entodermal origin

Answer 44

A,b,c

Question 45

Dental lamina: a) is present in both jaws b) shortly after its formation, it shows on each side of each jaw five regions of intensive mitotic activity c) develops on each side of each jaw five tooth buds as primordial of deciduous teeth d) regresses completely before the 5th week of the prenatal development

Answer 45

A,b,c

Question 46

The tooth buds: a) are of pure entodermal origin b) are accompanied by the condensation of the surrounding mesenchymal cells c) regress completely before the 5th week of the embryonic development d) are present only in the upper jaw

Answer 46

B

Question 47

Ectodermal epithelial cells: a) develop into ameloblasts b) develop into odontoblasts c) interact with neural crest-derived ectomesenchymal cells during the development of the teeth d) develop into cartilage

Answer 47

A,c

Question 48

During the teeth development: a) the bud stage is followed by the cap stage b) the crown stage is followed by the bud stage c) the permanent teeth begin to form in the 20th week of the prenatal development d) the teeth starts to develop from the labio-gingival groove

Answer 48

A,d

Question 49

The enamel organ of the tooth: a) is formed by pure entoderm b) consists of simple squamous epithelium c) contains the preameloblasts during its development d) becomes surrounded in the root region by the condensed mesenchyme

Answer 49

C,d

Question 50

The enamel organ of the tooth: a) is formed by the ectoderm b) consists of stratified epithelium that becomes subdivided in flattened outer and high inner enamel epithelium c) contains during its development the preameloblasts d) becomes surrounded by entoderm

Answer 50

A,b,c

Question 51

The enamel organ of the tooth: a) is formed by the mesoderm b) consists of stratified epithelium c) consists of epithelium that becomes subdivided in flattened outer and high inner enamel epithelium d) contains during its development the preameloblasts

Answer 51

B,c,d

Question 52

During the teeth development: a) the cap stage is followed by the bell stage b) the primordia of the last two molars of permanent teeth are not formed until after birth c) the crown stage is followed by the bud stage d) the teeth develop from the entodermal lining of the primitive gut

Answer 52

A,b

Question 53

During the bell stage of the tooth development: a) the inner epithelium of the enamel organ differentiates into ameloblasts b) the mesenchymal cells differentiate into ameloblasts c) the inner epithelium of entodermal origin differentiates into odontoblast d) the inner epithelium of entodermal origin differentiates into cartilage

Answer 53

A

Question 54

Ameloblasts: a) deposit the enamel matrix b) project on their base into conical extensions – Tomes’ processes c) after the end of secretory phase, the ameloblasts differentiate into odontoblasts d) degenerate during the bud stage of the tooth development

Answer 54

A,b

Question 55

Ameloblasts: a) are of the endodermal origin b) project on their base into conical extensions – Tomes’ processes c) after the end of secretory phase, the ameloblasts regulate the maturation of enamel d) degenerate during tooth eruption

Answer 55

B,c,d

Question 56

Odontoblasts: a) come from ameloblasts b) come from preodontoblasts of the dental papilla c) secrete procollagen which then matures in collagen fibrils of predentin d) degenerate to form the Tomes’ processes

Answer 56

B,c

Question 57

Dentin: a) resembles bone matrix in its composition b) from the histological point of view it is identical with compact bone c) contains ameloblasts d) contains blood vessels

Answer 57

A

Question 58

Tomes’ fibers in the tooth: a) are cytoplasmic processes of odontoblasts b) belong to ameloblasts c) are of entodermal origin d) degenerate before the 5th week of the embryonic development

Answer 58

A

Question 59

Which statements are correct about teeth development? a) the primary teeth start to form between the 6th and 8th week of the embryonic development b) the bud stage is followed by the cup stage c) the teeth start to develop from the cartilage d) teeth are of pure entodermal origin

Answer 59

A,b

Question 60

Which statement is correct about teeth development? a) the primary teeth do not contain the dental pulp with vessels and nerves b) the cup stage is followed by the bell stage c) the teeth starts to develop from the Rathke’s pouch d) teeth are of pure entodermal origin

Answer 60

B

Question 61

The respiratory system: a) develops as a derivative of the digestive system b) develops just behind the copula in the region of the fourth pharyngeal arch c) starts to develop in the form of a laryngo-tracheal groove d) is lined by cells of ectodermal origin

Answer 61

A,b,c

Question 62

The laryngo-tracheal diverticle: a) comes from the ectoderm b) develops from the laryngo-tracheal groove c) divides into a left and greater right plug d) grows parallel with the esophagus

Answer 62

B,c,d

Question 63

The laryngo-tracheal diverticle: a) develops from the laryngo-tracheal groove b) deepens and elongates as it grows ventral through the surrounding mesenchyme to form the respiratory passages c) becomes connected with the liver and spleen d) forms in healthy newborns under normal conditions as the tracheo-esophageal fistula

Answer 63

A,b

Question 64

During the prenatal development of the respiratory system: a) the whole respiratory part of the bronchial tree is finished and terminates in alveolar sacs in the 3rd week of development b) the lungs are lined by ectodermal lining c) the laryngo-tracheal diverticle develops from the laryngo-tracheal groove d) develops as a derivative of the digestive system

Answer 64

C,d

Question 65

During the prenatal development of the respiratory system: a) the whole respiratory part of the bronchial tree is finished and terminates in alveolar sacs in the 6th month of development b) the lungs are filled with amniotic fluid c) the lungs are fully and completely developed during the 3rd month of the deve- lopment and no alveoli are formed after delivery d) develops as a derivative of the digestive system

Answer 65

A,b,d

Question 66

The tracheo-esophageal fistula: a) can be combined with esophageal atresia b) leads to signs of respiratory distress as the saliva or milk enter the lungs c) always closes spontaneously and does not need any treatment d) can be repaired surgically

Answer 66

A,b,d

Question 67

The amniotic sac: a) encloses the amniotic cavity b) encloses the embryo c) contains the amniotic fluid d) is lined by cells of mesodermal origin

Answer 67

A,b,c

Question 68

The primitive gut: a) comes to form the ectodermal lining of the amniotic sac b) forms a large loop which projects out of the body c) contributes to the development of the liver and pancreas d) contributes to the development of the pituitary gland

Answer 68

B,c

Question 69

The greater curvature of the stomach: a) is formed at the end of the 4th week b) is formed by the gut tube that dilates in the dorsal direction c) is lined by ectodermal cells d) is gradually shifted to the left side

Answer 69

A,b,d

Question 70

The spleen: a) is entirely of pure ectodermal origin b) develops within the dorsal mesentery dorsal to the greater curvature of the stomach c) its primordium starts in the form of ectodermal thickening d) its mesenchyme is gradually filled with lymphoid elements

Answer 70

B,d

Question 71

The spleen: a) is of splanchnic mesodermal origin b) develops within the dorsal mesentery dorsal to the greater curvature of the stomach c) its primordium starts in the form of isolated spleen islands d) develops during the third week of embryonic development from the ectodermal lining

Answer 71

A,b,c

Question 72

The liver: a) is entirely of ectodermal origin b) develops from the gut tube c) starts as evagination that grows in the mesenchyme of the ventral mesentery d) is formed by the entodermal trabeculae that give rise to the parenchymal part of the liver tissue

Answer 72

B,c,d

Question 73

The gall bladder: a) develops together with the liver b) develops as a continuation of the liver diverticle c) originates from ectodermal lining d) its ductus cysticus unite with ductus hepaticus communis into ductus choledo- chus and finally opens together with the main pancreatic duct into hepatopan- creatic ampulla of the duodenum

Answer 73

A,b,d

Question 74

During the pancreas development: a) the larger dorsal pancreatic bud develops in the pharyngeal region b) the smaller ventral bud forms at first only as a protuberance of the liver diverticle c) the smaller ventral pancreatic bud becomes shifted medially during the rotation of the stomach d) finally both pancreatic buds take the dorsal position

Answer 74

B,c,d

Question 75

During the pancreas development: a) the larger dorsal pancreatic bud develops opposite the hepatic diverticle b) the smaller ventral bud regresses completely c) the smaller ventral part becomes the body and tail of the pancreas d) finally both buds fuse

Answer 75

A,d

Question 76

During the pancreas development: a) the dorsal part becomes the main body and tail of the pancreas b) the ventral bud forms only the lower part of the head and the uncinate process c) the main pancreatic duct is derived from the ventral bud d) both pancreatic buds never fuse and stay separated

Answer 76

A,b,c

Question 77

The endocrine Langerhans islands: a) come from the ectoderm b) are believed to come from some entodermal terminal cells of the duct system c) are of pure mesodermal origin d) insulin formation is active even before birth

Answer 77

B,d

Question 78

The cranial limb of the gut loop: a) elongates rapidly and forms an jejuno-ileal knot b) will form the small intestine c) is called Meckel’s diverticulum d) contributes to the branchial region development

Answer 78

A,b

Question 79

The caudal limb of the gut loop: a) gives rise to the development of thyroid gland b) gives rise to the large intestine c) contributes to the development of a small protrusion called caecal diverticulum d) regresses completely

Answer 79

B,c

Question 80

During the rotation of large intestine: a) the caecum passes at first cranially b) the small intestine grows rapidly and becomes thrown in many loops c) mesenteries tend to fuse against the dorsal body wall d) the spleen moves towards the right side and downwards

Answer 80

A,b,c