Development

Question 1

important concepts of embryonic development (4)

Answer 1

universal mechanisms of animal development
proteins can be substituted across species
inductive signaling
regional determination

Question 2

regional determination

Answer 2

once a tissue reaches a certain point in its developmental process, its destined to be that tissue

Question 3

signal proteins that are used over and over again as inducers in animal development (5)

Answer 3

receptor tyrosine kinase (RTK)
TGFB superfamily
Wnt
Hedgehog
Notch

Question 4

proteins can be substituted across

Answer 4

species

Question 5

multicellular organisms are enriched in

Answer 5

proteins mediating cell interactions and gene regulation

Question 6

regulatory DNA defines the

Answer 6

development program

Question 7

inductive signaling (4)

Answer 7

cell-cell signaling
cell signaling cascades
acts over great distances
starting point (cell or cell cluster)

Question 8

in inductive signaling, cells that are close get

Answer 8

a higher concentration of signal than those further away

Question 9

in inductive signaling, cells directed to new

Answer 9

developmental pathway

Question 10

sequential induction

Answer 10

initial induction induces changes to cells which induce changes to more cells, etc

Question 11

pre-somitic mesoderm from a thoracic vertebrae-forming region in transplanted from a state 10 chick embryo into the cervical region of a state 8 embryo

Answer 11

skeleton of recipient embryo at 9 days shows cervical vertebrae developing as thoracic vertebrae

Question 12

what are the four essential processes by which an embryo is constructed?

Answer 12

cell proliferation
cell specialization
cell interaction
cell movement

Question 13

— — vary greatly across the animal kingdom

Answer 13

gestational periods

Question 14

patterning

Answer 14

cells produced by cleavage get organized into layers and groups of cell masses through gastrulation

Question 15

patterning needs to occur in - dimensions

Answer 15

3

Question 16

what are the 3 dimensions of patterning

Answer 16

anterior-posterior (top to bottom)
dorsal-ventral (left-right)
proximal-distal (front-back)

Question 17

differentiation

Answer 17

cells begin to form specific and specialized structures

Question 18

growth

Answer 18

cell divisions that form more cells with identical functions as the parental cell

Question 19

paradigm of development

Answer 19

in every species and at every level of organization, complex structures are made by repeating a few basic themes with variations

Question 20

similarities in embryos if different species provides evidence of

Answer 20

common ancestor
(patterns of embryo development are also important)

Question 21

primitive streak

Answer 21

forms as an influx of cells into the interior to form the 3 cell layers (mesoderm, endoderm, ectoderm)

Question 22

neural crest cells

Answer 22

embryonic cell population that is localized between the developing neural tube and the non-neural ectoderm. (there are also adult neural crest cells like cells that have been identified in many tissues)

Question 23

some neural crest cell exhibit “—” in that they can give rise to multiple differentiated cell types

Answer 23

stemness

Question 24

in the formation of the crainofacial structures (and many other structures) the neural crest cells migrate through

Answer 24

restricted pathways to form the developing structures

Question 25

cell migration is a tightly regulated process and the NCCs receive cues such as

Answer 25

morphogens and growth factors that restrict their movement and determine fate

Question 26

segmental plate mesoderm gives rise to

Answer 26

epithelial somites

Question 27

epithelial somites give rise to (2)

Answer 27

dermamyotome | sclerotome

Question 28

dermamyotome gives rise to (2)

Answer 28

dermatome | myotome

Question 29

hierarchical gene control

Answer 29

``` coordinate genes gap genes air rule genes segment polarity genes homeotic selector genes other genes ```

Question 30

homeosis

Answer 30

replacement of one body part with another

Question 31

ed lewis reasoned that these were genes responsible for

Answer 31

establishing the fate of individual segments

Question 32

gene products are

Answer 32

gene regulatory proteins

Question 33

all contain a highly conserved

Answer 33

DNA binding homeodomain sequence of 60 amino acids

Question 34

the corresponding segment in the 180 bp DNA sequence is called a

Answer 34

homeobox

Question 35

how genes are interspersed among large stretches of

Answer 35

regulatory DNAregions

Question 36

how genes are expressed --- according to their order in the hot complex

Answer 36

sequentially

Question 37

how complex carries a permanent record of

Answer 37

positional information

Question 38

there are hundreds of other homeobox genes in the genome, bu they are

Answer 38

scattered and not cluster in complexes

Question 39

pattern of gene expression of each gene follows

Answer 39

head to tail and order on chromosomes

Question 40

a homeobox code drives

Answer 40

tooth formation

Question 41

when does cleft lip and palate occur?

Answer 41

early in fetal development. in humans, the lip forms between the 4th and 7th week of pregnancy and the palate forms between weeks 6 and 9

Question 42

formation of the craniofacial structures in early development requires the proper migration of

Answer 42

neural crest cells and their differentiation

Question 43

there are universal mechanisms of development that are essentially used by

Answer 43

all animals, including invertebrates

Question 44

the complexity of animals is a function of the

Answer 44

gene expression control systems that drives development

Question 45

multicellular organisms are enriched in proteins that (2)

Answer 45

mediate cell-cell interactions and control gene expression

Question 46

cells in the adult organism retain a record of

Answer 46

signals they received in early embryonic development, which is necessary. for them to maintain their specialized characteristics