Intro To Developmental Biology

Question 1

During cleavage divisions, does the cell grow in size?

Answer 1

No

Question 2

What 2 components make up the blastocyst?

Answer 2

The trophoblast and the inner cell mass

Question 3

What 2 components does the inner cell mass divide into?

Answer 3

The epiblast and the hypoblast

Question 4

What does the epiblast form?

Answer 4

The embryo proper (ectoderm, mesoderm and endoderm) and the amniotic membrane

Question 5

What does the hypoblast form?

Answer 5

Heuser’s membrane (primary yolk sac)

Question 6

What does the trophoblast form?

Answer 6

The chorion

Question 7

Where are the embryonic stem cells derived from?

Answer 7

The inner cell mass

Question 8

What are the 4 main derivatives of the mesoderm?

Answer 8

Notochord, somite, intermediate mesoderm, lateral plate mesoderm

Question 9

What happens to the epiblast cells during gastrulation?

Answer 9

They migrate to, and pass through, the primitive streak and node (ingression)

Question 10

What signals the ectoderm to form the neural plate?

Answer 10

The notochord

Question 11

When does the neural tube close?

Answer 11

Begins end of week 3, complete by end of week 4

Question 12

When does the embryonic disk start to fold?

Answer 12

Week 4

Question 13

Define neural crest cells

Answer 13

Migratory cells from the dorsal neural tube

Question 14

When are somites formed?

Answer 14

Day 20-30

Question 15

What tissues are formed by somites?

Answer 15

Dermatome, myotome and sclerotome

Question 16

What does the dermatome give rise to?

Answer 16

Dermal layer of skin

Question 17

What does the myotome give rise to?

Answer 17

Skeletal muscle

Question 18

What does the sclerotome give rise to?

Answer 18

Cartilage and bone of the occipital bone and axial skeleton

Question 19

What are the 5 neural tube regions?

Answer 19

Telencephalon, diencephalon, mesencephalon, rhombencephalon, spinal cord

Question 20

What does the intermediate mesoderm give rise to?

Answer 20

Reproductive system (excluding germ cells) and kidneys

Question 21

What are the 2 components of the lateral plate mesoderm?

Answer 21

Somatic layer (outer) and splanchnic layer (inner)

Question 22

What does the splanchnic layer of lateral mesoderm give rise to?

Answer 22

Blood, heart, blood vessels, muscles of gut

Question 23

What does the somatic layer of lateral plate mesoderm give rise to?

Answer 23

Limb skeleton and connective tissue

Question 24

What is the coelum and what does it give rise to?

Answer 24

Space between the somatic and splanchnic layers. It gives use to the pleural, pericardial and peritoneal cavities

Question 25

What are the 4 main vertebrate model organisms?

Answer 25

Mouse, chick, frog, zebrafish

Question 26

Which gene is responsible for eye formation?

Answer 26

Pax6

Question 27

What 2 cell types can stem cells give rise to?

Answer 27

Progenitor cells, more stem cells

Question 28

What is an example of epithelial to mesenchymal transition?

Answer 28

Neural crest

Question 29

What is an example of mesenchymal to epithelial transition?

Answer 29

Formation of gut tube from migratory epithelium

Question 30

Which 3 regions interact to generate cell behaviours and differentiation?

Answer 30

Cell surface receptors, cytoplasm and nucleus

Question 31

Which signalling pathway is involved in FGF and VEGF signalling?

Answer 31

Receptor tyrosine kinase

Question 32

Binding of BMP to a receptor triggers phosphorylation o which protein?

Answer 32

SMADs

Question 33

What happens to the patched and smoothened receptors when sonic hedgehog is present?

Answer 33

Shh binds to patched which stabilises smoothened

Question 34

What happens to the patched and smoothened receptors when shh is not present?

Answer 34

They are internalised and the Gli activators are degraded. Gli target genes are switched off.

Question 35

Which receptor does wnt bind to?

Answer 35

Frizzeled

Question 36

The binding of which ligands triggers notch signalling?

Answer 36

Delta and jagged