Lecture 2

Question 1

Gastrulation

Answer 1

cell movement from ball into 3 layered structure known as gastrula

Question 2

invagination

Answer 2

sheet of cells moving inward by apical constriction of actin fibers

Question 3

ingression

Answer 3

individual cells leave an epithelial state/sheet and become freely moving (mesenchymal)

Question 4

mesenchymal

Answer 4

freely moving cells

Question 5

epiboly

Answer 5

sheet of cells thinning out to become longer

Question 6

intercalation

Answer 6

rows of cells moving in between each other to become longer

Question 7

ingression is similar to

Answer 7

this process is similar to that used by carcinoma cells to extravasate and metastasize

Question 8

three layers of cells

Answer 8

ectoderm, mesoderm and endoderm

Question 9

cadherins are

Answer 9

cell adhesion molecules

Question 10

some things in ECM (extracellular matrix) are

Answer 10

collagen, proteoglycans, glycoproteins

Question 11

Xenopus leavis

Answer 11

frog

Question 12

What ,in frogs, triggers the opening of a pore that allows cells on outside of embryo to move inside?

Answer 12

Spemann’s organizer

Question 13

what is the hole formed by Spemann’s organizer?

Answer 13

blastopore- in frogs only

Question 14

Where does blastpore form?

Answer 14

dorsal lip of blastocyst

Question 15

Transcription factor expressed in the dorsal marginal region that is involved in starting gastrulation in frogs

Answer 15

goosecoid

Question 16

explain basic steps of activation of gastrulation

Answer 16

receptors attach to cells and get activated by ligand

starts signal transduction cascade in cytoplasm

leads to activation of transcription factors in the nulceus and gene expression

Question 17

examples of glycoproteins in extracellular matrix

Answer 17

fibronectin, chondronectin, tenascin

Question 18

outer ectoderm cells move by what to move into cell in frogs

Answer 18

epiboly (sheet movement by thinning out)

Question 19

first thing to form from mesoderm

Answer 19

notochord from chorda mesoderm

Question 20

types of mesoderm

Answer 20

notochord,

PARAXIAL MESODERM (somites)
INTERMEDIATE MESODERM (kidneys and gonads) 
LATERAL MESODERM (splanchnic (internal organs, blood endothelium) and somatic (limb skeleton, ventral skin dermis and connective tissue of body cavity)

Question 21

A blastula of a chick is in what shape

Answer 21

blastodisc

Question 22

Inner cell membrane turns into

Answer 22

epiblast and hypoblast

Question 23

groove in bird and mammal gastrulation similar to blastopore in frog

Answer 23

primitive streak

Question 24

This induces the formation of the primitive streak in bird

Answer 24

koller’s sickle

Question 25

structure in birds that is similar to Spemann's organizer, that triggers cells to enter center of blastocyst

Answer 25

hensen's node

Question 26

cells in birds and mammals move into cell in a ___ way

Answer 26

mesenchymal

Question 27

Mammals do not need large yolk sac because of this ___

Answer 27

placenta

Question 28

placenta is made from these cells

Answer 28

trophoblast

Question 29

structure in mammals, that is similar to Spemann's organizer, that triggers cells to enter center of blastocyst

Answer 29

node

Question 30

once gastrulation completes primitive steak regresses and leaves ___ behind

Answer 30

notochord

Question 31

notochord is made of what type of cells

Answer 31

mesoderm

Question 32

process by which ectoderm forms a neural plate and folds into neural tube

Answer 32

neurulation

Question 33

embryonic precursor to the central nervous system (brain and spinal cord)

Answer 33

neural plate which turns into neural tube

Question 34

explain neurulation

Answer 34

notochord stimulates ectoderm to thicken into the neural crest and invaginate onto itself creating the neural tube. neural crest cells change states and travel all over body to form bones, melanocytes and neurons

Question 35

what causes neurulation

Answer 35

BMP

Question 36

what inhibits neurulation

Answer 36

Noggin/ chordin

Question 37

what is the name of the process through which the notochord causes neurulation

Answer 37

neural induction

Question 38

neural tube closure in chicks happens at **

Answer 38

level of future midbrain and zips up in either direction

Question 39

neural tube closure in mammals happens

Answer 39

at multiple locations

Question 40

the last regions of the neural tube to close are

Answer 40

cranial and caudal neuropores

Question 41

lethal condition when anterior/ cranial neuropore does not close correctly

Answer 41

anencephaly

Question 42

condition when caudal neuropore does not close correctly

Answer 42

spina bifida cystica

Question 43

neural tube changes into

Answer 43

forebrain, midbrain and hindbrain

Question 44

another name for forbrain

Answer 44

prosencephalon

Question 45

another name for midbrain

Answer 45

mesencephalon

Question 46

another name fir hindbrain

Answer 46

rhombencephalon

Question 47

neural tube defect where skin fails to separate from the spine in rhodesian ridgebacks

Answer 47

dermoid sinus

Question 48

duplication of what factors make rhodesian ridgebacks more predisposed to dermoid sinus

Answer 48

FGF3, FGF4, FGF19 and ORAOV1

Question 49

rhodesian ridgeback breeders are not allowed to breed ___ with ___

Answer 49

ridged with ridged

Question 50

two examples of cell adhesion molecules

Answer 50

cadherins and CAMS

Question 51

example of cell junction molecule

Answer 51

gap-junctions-connexins

Question 52

what is EMT , give example

Answer 52

epithelial to mesenchymal | neural crest cells