Anderson Review Qns

Question 1

In early heart formation, cells migrating through the anterior part of the primitive streak will form which of the components of the heart?

Answer 1

forms outflow tract

Question 2

In the early embryo, during somitogenesis, how many somitomere pairs are found caudal to the most caudal somite pair?

Answer 2

1st pair of somites forms behind (caudal to) 7th pair of somitomeres at the expense of the 8th pair of somitomeres
-11 pairs of somitomeres kept constant at caudal end of paraxial mesoderm

Question 3

Opposing FGF-8 and retinoic acid gradients associated with which theory regarding somite formation?

Answer 3

wavefront or determination front model of somitogenesis

Question 4

The sclerotome is derived from cells from what source?

Answer 4

paraxial mesoderm

Question 5

what is the source of the cardiogenic plate?

Answer 5

splanchnic mesoderm

Question 6

An inductive stimulus from what source stimulates the transformation of the epithelial sclerotome into secondary mesenhcyme?

Answer 6

notochord

Question 7

What type of embryonic defects are characterized as primary errors of morphogenesis that are usually multifactorial and involve a number of etiological agents including genetic and environmental factors?

Answer 7

malformations

Question 8

What condition refers to the accumulation of edema fluid in the fetus during intauterine growth?

Answer 8

hydrops

Question 9

Folic acid deficiency is now thought to be a major cause of what class of malformations?

Answer 9

neural tube defects

Question 10

Anal atresia can be attributed to what type of disturbance?

Answer 10

disturbance in tissue resorption

Question 11

What group of congenital malformations makes up the largest percentage of congenital malformations?

Answer 11

UNKNOWN FACTORS

Question 12

The intermediate mesoderm in the early embryo gives rise to which system(s)/structures?

Answer 12

urogenital system

Question 13

Cleft palate is the result of a defect in what developmental mechanism?

Answer 13

failure to fuse

Question 14

Phocomelia is most likely to be seen after maternal exposure to which teratogenic agent during the first trimester of pregnancy?

Answer 14

Thalidomide

Question 15

What are the characteristic effects caused by exposure of the fetus to alcohol?

Answer 15

-growth and mental retardation
-microcehaly
-face and trunk malformations
- heart defects
holoprosencephaly=severe

Question 16

Supplementing the diet of women of childbearing age with which dietary supplement may reduce the incidence of neural tube defects such as anencepahly?

Answer 16

folic acid

Question 17

In fetal hydrops, the affected brain may become enlarged and edamatous and, when sectioned, has a bright yellow color, particularly the bsal nuclei, thalamus, cerebellum, cerebral gray, and spinal cord. What term is related to this CNS damage?

Answer 17

kernicturus

Question 18

An increased incidence of what conditions is strongly associated with increasing maternal age?

Answer 18

trisomy 21

Question 19

During childbirth, which membranes/layers around the embryo rupture and which do not?

Answer 19

layers that rupture-amnion and chorion

layers that don’t rupture—>allantois and secondary umbilical vesicle

Question 20

Tendons of limb muscles arise from what source?

Answer 20

lateral plate mesoderm

Question 21

Limb muscles arise from what source?

Answer 21

ventrolateral dermomyotome

Question 22

Expression of what genes are involved in the separation of the dermomyotome into dorsal dermatome and ventral myotome?

Answer 22

expression of Pax 3, Pax 7, and Paraxis

Question 23

In early heart formation, cells migrating through the middle part of the primitive streak will form which of the hearts components?

Answer 23

form ventricles

Question 24

In early heart formation, cells migrating through the anterior part of the primitive streak will form which of the heart components?

Answer 24

form outflow tract

Question 25

In early heart formation, cells migrating through the posterior part of the primitive streak will form which of the heart components?

Answer 25

form the atria

Question 26

hydatidform mole is related to which genetic-related condition?

Answer 26

paternal imprinting

Question 27

formation of ribs on the lumbar and sacral vertebrae occurs as a result of what genetic condition?

Answer 27

knockout of all Hox 10 paralogues

Question 28

Myoepithelial cells in the lactating breast contract in response to what hormone?

Answer 28

oxytocin

Question 29

Which components of the hair and its follicle are derived from ectoderm?

Answer 29

- hair follicle -nails -hair shaft | - sebaceous glands -secretory and duct components of mammary gland

Question 30

Which components of the hair and its follicle are derived from mesoderm?

Answer 30

arrector pilli

Question 31

The proatlas anlage contributes to the formation of which structures?

Answer 31

fuses with 3 upper occipital sclerotomes to form the OCCIPITAL BONE

Question 32

What factor is antagonistic to BMP and, when down regulated, allows sutures to fuse?

Answer 32

Noggin

Question 33

what structure is/are derived from the trophoblast?

Answer 33

placenta and chorion | -forms outer layer of blastocyst

Question 34

List/describe factors/conditions that facilitate the exchange of oxygen between the fetal and maternal blood.

Answer 34

Bohr effect--- fetal blood can carry greater quantity of Oxygen than maternal blood for given blood P02--> delivers increased O2 to the tissues Double Bohr effect---double shift in maternal blood and fetal blood fetal blood hemoglobin concentration is about 50% greater than maternal fetal hemoglobin has a higher affinity for O2

Question 35

What factor is in the permanent cartilage pathway that causes chondroblasts to secrete collagen II and cartilage matrix and is continually expressed in permanent cartilage?

Answer 35

sox 9

Question 36

What is/are the effects of HCG on the corpus luteum?

Answer 36

- prevents involution of corpus luteum (CL) - causes CL to increase secretion of progesterone and estrogens - causes increased growth in CL

Question 37

What cells can be considered immigrant with regard to the development of integument?

Answer 37

1. melanoblasts--from neural crest 2. Langerhan's cells--from bone marrow 3. Merkel cells--from neural crest

Question 38

Describe the characteristics of satellite cells in reference to muscle tissue differentiation

Answer 38

- able to fuse with muscle fiber and provide growth - cannot form new muscle fibers - fxn as stem cells - give rise to myogenic precursor cells---replace damaged muscle by proliferating, fusing, and differentiating into skeletal muscle fibers

Question 39

What signaling molecules are expressed by the isthmic organizer?

Answer 39

mostly FGF-8, Wnt-1, En-1, En-2

Question 40

What germ layers make up each of the extraembryonic membranes?

Answer 40

amnion--inner cell mass: epiblast derivative yolk sac-inner cell mass: hypoblast derivative allantois-inner cell mass; interfaces with placenta via umbilical cord chorion--part of fetal maternal interface

Question 41

What germ layer is absent from the oropharyngeal membrane?

Answer 41

-lack of mesoderm-->result in perforation of these plates

Question 42

List the characteristics of the early placenta and relate to the late placenta

Answer 42

Early--thick, low permeability, small SA, total diffusion conductance is minuscule Late--thin, high permeability, large SA, large increase in placental diffusion

Question 43

Name the factors that is/are involved in the formation of rhombomeres 3 and 5

Answer 43

Krox-20

Question 44

Describe the 3 circulatory arcs and their components in the 4-week embryo

Answer 44

vitelline arc-vitelline vessels allantoic arc---allantoic (umbilical) vessels embryonic arc--dorsal aorta, aortic arches, anterior cardinal vein, common cardinal vein, posterior cardinal vein, atrium, ventricle, ventral aorta

Question 45

What transcription factor suppresses the formation of anterior gut structures and promotes hindgut development?

Answer 45

Cdx-2

Question 46

At what time during pregnancy does maximum secretion of HCG occur?

Answer 46

10th-12th week of pregnancy

Question 47

What role does p63 play in the formation of the intermediate layer of the epidermis and what is its relation to miR-203?

Answer 47

p63 initiates 3-layered epidermis-forms )basal germinative layer) and superficial peridermal layer miR-203---inactivates p63 which allows intermediate layer to form

Question 48

What is fillagrin and what is it specifically associated with?

Answer 48

Fillagrin---> filament associated protein that binds to keratin fibers in epithelial cells --it interconnects the stratum granulosum of intermediate layer of the epidermis

Question 49

Compare permissive and instructive induction and give examples.

Answer 49

permissive induction---responding tissue has all the potentials that are to be expressed, and need only an environment that allows the expression of the traits ex. fibronectin/laminin does not alter the type of cell that is to be produced, but only enables what has been determined to be expressed instructive induction----> signal from inducing cell necessary for initiating new gene expression in the responding cell- need for differentiating ex. optic vesicle places under region of ectoderm causing region of ectoderm to from a lens

Question 50

Which intramembranous bone in the body is the first to become ossified?

Answer 50

the clavicle

Question 51

Prechordal (hypophyseal) cartilages contribute to the formation of which components of the embryonic skull?

Answer 51

basisphenoid bone

Question 52

List characteristicss of early cardiac muscle cells

Answer 52

- does not express Myo D - contract early - maintains their ability to divide partially disassembling their contractile apparatus prior to cell division

Question 53

Parachordal cartilages contribute to the formation of which components of the embryonic skull?

Answer 53

basioccipital portion of chondrocranium

Question 54

What skull structures are derived from the membranous portion of the viscerocranium?

Answer 54

- part of the temporal -palatine - zygomatic -vomer - maxillary -pterygoid plates, mandible - nasal - lacrimal - tympanic ring

Question 55

Name the four components of the typical embryonic pharyngeal arch

Answer 55

1. skeletal element 2. muscles 3. branch of specific cranial nerve 4. artery