Genetics of Development

Question 1

A cell can be removed in what phase during pre-implantation diagnosis?

Answer 1

Morula

Question 2

What is the first axis visible in the embryo?

Answer 2

anterior-posterior

Question 3

What structure defines the anterior posterior axis?

Answer 3

primitive streak

Question 4

What does the primitive streak mark?

Answer 4

Where ectodermal cells invade the space between the epiblast and the hypoblast

Question 5

What does the ectoderm form?

Answer 5

skin and nervous system

Question 6

What does mesoderm form?

Answer 6

bone, muscle and most internal organs

Question 7

What will the endoderm form?

Answer 7

cells of the gut and lung epithelium

Question 8

Where is the node located?

Answer 8

at the anterior end of the primitive streak

Question 9

What is the function of noggin and chordin?

Answer 9

to induce dorsal development

Question 10

Where are noggin and chordin released from?

Answer 10

the node

Question 11

Where is Shh released from?

Answer 11

notochord

Question 12

What is the function of Shh?

Answer 12

right/left asymmetry

Question 13

What is situs inversus?

Answer 13

where internal organs are a mirror image of what is normally found

Question 14

What is the condition called where the organs are randomized in their location?

Answer 14

situs ambiguus

Question 15

What is situs ambiguus usually accompanied with?

Answer 15

heart defects

Question 16

What is the function of the homeobox (HOX) genes?

Answer 16

patterning along the anterior/posterior axis

Question 17

What is patterning?

Answer 17

determining what part of the embryo divides into specific parts

Question 18

What are malformations?

Answer 18

an intrinsic abnormality in the developmental process

Question 19

What do deformations result from?

Answer 19

extrinsic influence on the development of an organism

Question 20

What do disruptions result from?

Answer 20

destruction of developing tissue

Question 21

What is a sequence?

Answer 21

a cascade of events resulting from a single anomaly

Question 22

What is a syndrome?

Answer 22

when all disease phenotypes are caused by a single defect

Question 23

What do defects arising between 1-4 weeks development produce?

Answer 23

multiple organ abnormalities

VACTERL

Question 24

What is a major risk factor for VACTERL defects?

Answer 24

maternal diabetes

Question 25

What do abnormalities occurring from week 5 to 8 affect?

Answer 25

specific organs to produce specific anomalies

Question 26

What are cells during the regulative phase?

Answer 26

functionally equivalent

Question 27

A morula is in what phase of development?

Answer 27

regulative

Question 28

A loss of a cell in the mosaic phase results in what?

Answer 28

loss of tissue the cell was destined to become

Question 29

The primitive streak is formed by what type of cells?

Answer 29

Ectoderm

Question 30

What is the first visible axis in the embryo?

Answer 30

anterior/posterior axis

Question 31

What is the anterior/posterior axis defined by?

Answer 31

primitive streak

Question 32

What two proteins are secreted from the node?

Answer 32

noggin and chordin

Question 33

What are the functions of noggin and chordin?

Answer 33

induce dorsal development in a concentration dependent manner

Question 34

Where is the node located?

Answer 34

anterior end of primitive streak

Question 35

What protein is responsible for left/right asymmetry?

Answer 35

Shh

Question 36

Where is Shh secreted from?

Answer 36

notochord

Question 37

Asymmetric expression of Shh leads to left sided expression of what protein?

Answer 37

Nodal

Question 38

A defect in left/right formation is referred to as what?

Answer 38

situs inversus

Question 39

What describes a condition in which organs are randomized in their location?

Answer 39

situs ambiguus

Question 40

Patterning along the anterior/posterior axis is controlled by what family of genes?

Answer 40

HOX

Question 41

What causes malformations?

Answer 41

intrinsic abnormality

Question 42

What causes deformations?

Answer 42

extrinsic influence

Question 43

What causes disruptions?

Answer 43

result from the destruction of developing tissue

Question 44

Isolated anomalies affect what?

Answer 44

a single body region

Question 45

What is a sequence?

Answer 45

cascade of events starting from an anomaly

Question 46

What do syndromes affect?

Answer 46

several body regions

Question 47

What kind of inheritance do syndromes possess?

Answer 47

Mendelian

Question 48

When do abnormalities that affect single organ systems originate?

Answer 48

week 5 to 8

Question 49

Defects in the weeks of 1-4 can be characterized by what acronym?

Answer 49

VACTERL

Question 50

What maternal behavior is a risk for VACTERL?

Answer 50

diabetes

Question 51

In order, what is the order of the most common congenital malformations?

Answer 51

heart defects, pyloric stenosis, neural tube defects, orofacial clefts, clubfoot

Question 52

Where is the node located?

Answer 52

anterior end of primitive streak

Question 53

Where are noggin and chrodin secreted from? What is their function?

Answer 53

the node induce dorsal development

Question 54

Where is Shh secreted from? What is its function?

Answer 54

notochord right/left development

Question 55

What gene is required for the formation of the primitive streak?

Answer 55

Nodal

Question 56

What two conditions can arise from defects in right/left development?

Answer 56

situs inversus and situs ambiguus

Question 57

What is the function of the HOX genes?

Answer 57

to develop patterning along the anterior/posterior axis

Question 58

What disease does the Philadelphia Chromosome cause?

Answer 58

acute myeloid leukemia