1 - Embryonic Development

Question 1

Epithelial Cells Description

Answer 1

Polarised cells, tight junctions, apical / basolateral

Line cavities or hollow structures

Seal off underlying tissue

Creation of compartments, separation of inside from outside

Question 2

Epithelial Cells Function

Answer 2

Protection

Question 3

Mesenchymal Cells Description

Answer 3

Non-polarised cells

Migratory

Question 4

Mesenchymal Cells Function

Answer 4

Support Tissues

Question 5

Neural Crest - how do cells get specified (induction of the crest)

Answer 5

Medium levels of BMP induce neural crest, activation of transcription factors, activation of snail which regulates the transition of epithelial to mesenchymal transition

Question 6

Neural Crest - how do cells get specified (signalling molecules)

Answer 6

induce expression of downstream effector genes (identify cells and tissue)

Question 7

What does EMT stand for?

Answer 7

Epithelial mesenchymal transition

Question 8

EMT function?

Answer 8

Necessary for cells to become migratory

Question 9

What’s cell migration

Answer 9

Present or absence of molecules

Question 10

Cell-cell contact as Signalling Mechanism

Answer 10

Cell adhesion molecules (CAM)

E-caderin (surface ectoderm)

N-caderin (neural tissue)

Question 11

Cell differentiation stages

Answer 11

Neural crest cells contribute to the fomration of the facial skeleton

Cranial neural crest differentation is regulated by BMP levels

Question 12

Signalling factors

Answer 12

BMP

Wnt

FGF

Question 13

Cell adhesion molecules

Answer 13

E-Cadherin

N-Cadherin

Question 14

Identity

Answer 14

neural crest

surface ectoderm and neural tissue

transcription factors

Question 15

Migration

Answer 15

EMT (loss of epithelial characteristics)

Question 16

Differentiation

Answer 16

cartilage vs bone

Question 17

Stem cells and development - haematopoiesis

Answer 17

Generation of blood cells (throughout life

Capacity to give rise to a large number of specialised cells

In bone marrow)

Question 18

Why does haematopoiesis migrate into the bone marrow

Answer 18

provides the stem cell with optimal environment (promotes self rem)

Question 19

Snail

Answer 19

Turns off epithelial cells

Helps cells lose their ‘stuck in place’ identity so they can move

Switches on mesenchymal genes – making the cells more flexible and migratory

Question 20

Without Snail, EMT wouldn’t happen properly

Answer 20

And if EMT doesn’t happen, cells like the neural crest can’t move

Can’t reach the places they need to be to build stuff (Eg. Face bones)

Question 21

Medium levels of BMP

Answer 21

form neural crest cells

Question 22

High levels of BMP

Answer 22

make epidermis (outer skin)

Question 23

Low levels of BMP

Answer 23

make neural tissue (brain/spinal cord)

Question 24

BMP

Answer 24

Bone Morphogenetic Protein

Question 25

BMP function

Answer 25

Decides what type of cell a cell should become Controls levels of differentiation

Question 26

Wnt

Answer 26

Tells cells where they are and helps form neural crest Works with BMP to fine-tune development

Question 27

FGF

Answer 27

Fibroblast Growth Factor Stimulates growth, limb formation, and mesoderm development