Development

Question 1

Which concept of embryonic development is best associated with morphogens and morphogen gradients?

a. inductive signaling
b. substitution of proteins across species
c. universal mechanisms
d. regional determination

Answer 1

a. inductive signaling

Question 2

what does the genome allow?

Answer 2

complete development of an organism

Question 3

What is the transcriptome?

Answer 3

all of the RNA that is present

Question 4

What is the proteome?

Answer 4

all of the proteins that are present

Question 5

What factors modulate gene expression and cell function?

Answer 5

growth factors, hormones, force/tension, nutrients, oxygen levels, and many other

Question 6

What are some of the evolutionarily conserved pathways?

Answer 6

-receptor tyrosine kinase
-TGFb superfamily
-Wnt
-Hedgehog
-Notch

Question 7

What does it mean if something is evolutionarily conserved?

Answer 7

the function is the same or similar in many or all organisms

Question 8

How does the Wnt pathway work? (i don’t think he would ask this)

Answer 8

Wnt ligand binds to Frizzled and LRP5/6
-causes other things to bind
-allows for phosphorylation event
-promote high affinity binding of cytosolic proteins
-inhibit the degradation of B-catenin
-B-catenin will move into the nucleus and turn on gene expression

Question 9

What are the four main cellular processes employed during embryogenesis?

Answer 9

-cell proliferation
-cell specialization
-cell interaction
-cell movement

Question 10

What is a fifth cellular processes that helps to fine tune development?

Answer 10

programmed cell death

Question 11

What are homeobox codes?

Answer 11

-helix-turn-helix transcription factors that integrate into the major groove of the DNA and work with other proteins to turn on gene expression

Question 12

What is homeotic transformation?

Answer 12

replacement of one body part with another

Question 13

What is unique about HOX gene location?

Answer 13

they are located linearly on a single chromosome (i think in humans they are many locations)

Question 14

What do HOX genes do for body development?

Answer 14

determine regional identity to the body plan

Question 15

Where are there no HOX genes in vertebrates?

Answer 15

in the face
-other than in the ear
-helps to form the bones

Question 16

How does the face develop without HOX genes?

Answer 16

it has its own set of specific homeobox related code

Question 17

What is a morphogen?

Answer 17

signalling factor that directs cell fate (tissue development) at a distance from their source

Question 18

Cell near the signaling factor get…

Answer 18

high levels of the signal

Question 19

Cells farther from the cell signaling factor get…

Answer 19

low levels of the signal

Question 20

Characteristics of inductive signaling:

Answer 20

-time and duration dependent
-different cell fates
-tissue patterning
-signaling gradient

Question 21

What are the axes of the face?

Answer 21

-left-right
-dorsal-ventral
-anterior-posterior

Question 22

What two things are considered for clinical treatment?

Answer 22

-form and symmetry

Question 23

When is the dorsal-ventral axis formed?

Answer 23

apparent by the blastocyte stage

Question 24

When does the first major cell development change during embryonic development?

Answer 24

from the 32 cell stage (morula) to the 64 cell stage (blastocyte)

Question 25

What causes the change from the morula to the blastocyte?

Answer 25

many different factors -external pressure -oxygen levels -other things

Question 26

What type of cell in development will give rise to every cell in the body?

Answer 26

inner cell mass

Question 27

What is the mesoderm?

Answer 27

the middle layer of the developing embryo -will become the mesenchyme

Question 28

When do the Left-right and anterior-posterior axes become apparent?

Answer 28

when the mesoderm is formed -the formation of the primitive streak

Question 29

What is the primitive streak?

Answer 29

epiblastic cells that converge at the midline and ingress (marks posterior end)

Question 30

What are the three germ layers?

Answer 30

-ectoderm -mesoderm -endoderm

Question 31

What is it called when cells of epiblast layer move through the primitive streak to form mesoderm?

Answer 31

epithelial to mesenchyme transformation (EMT)

Question 32

What is the node?

Answer 32

it is a signaling center that induces and specifies the fate of the mesoderm as it is formed -stimulate cells as they pass through

Question 33

What does the node create?

Answer 33

asymmetry in a previously symmetrical embryo -allows asymmetrical organogenesis

Question 34

What do nodal cells have?

Answer 34

one motile cilium

Question 35

What is cilium?

Answer 35

membrane covered extension from the cell that has a microtubule cytoskeleton core which helps define the properties of the cilium

Question 36

What kind of movement do nodal cilia have?

Answer 36

rotational beat (for a few hours only) -generate leftward flow, resulting in asymmetrical distribution of morphogens/growth factors

Question 37

How many genes in mice affect L-R asymmetry?

Answer 37

around 27

Question 38

What causes situs inversus?

Answer 38

affected cilia function that does not allow the organs to migrate properly during development

Question 39

What cells drive the rapid outgrowth of facial tissue and proliferation and ventral migrations of cells form the crest?

Answer 39

cranial neural crest cells

Question 40

What causes the formation of neural crest cells?

Answer 40

EMT

Question 41

What do the cranial neural crest cells give rise to?

Answer 41

many things -they are basically like another stem cell layer -parts of mandible and muscles of mouth

Question 42

Where is there a distinct population of cranial neural crest cells?

Answer 42

in the hindbrain -define the routes of migration into early facial tissue

Question 43

What causes Treacher-Collins syndrome?

Answer 43

defects in RNA polymerase I and TCOF1 (ribosomal biogenesis factor) -impact on CNCC survival

Question 44

What helps to create the boundary of expression in face?

Answer 44

ectoderm

Question 45

What type of process is embryogenesis?

Answer 45

generative -not descriptive

Question 46

What helps to develop the plasticity of cells?

Answer 46

communication from both distant and nearby cells