Developmental biology practical

Question 1

organogenesis

Answer 1

During the establishment of the body plan, at the appropriate position within the embryo,
local development of organs and organ systems takes place

During the establishment of the body plan, at the appropriate position within the embryo,
local development of organs and organ systems takes place

Question 2

cleavage

Answer 2

forms a hollow ball or disc of cells/blastula/blastoderm

Question 3

gastrulation

Answer 3

turns the blastula into a 3 germ-layered gastrula

Question 4

neurulation

Answer 4

special type of organogenesis - sets cells aside and forms the entire nervous system

Question 5

what are the 3 germ layers of the gastrula

Answer 5

ectoderm
mesoderm
endoderm

Question 6

ectoderm

Answer 6

gives rise to the nervous system

Question 7

mesoderm

Answer 7

blood, bone, muscle and mesodermal organs

Question 8

endoderm

Answer 8

digestive tract, respiratory tract and associated organs like the lungs and the liver

Question 9

Archenteron

Answer 9

the future gut

Question 10

3 steps in building an animal embryo

Answer 10

1. cell division
2. cells differentiation
3. morphogenesis

Question 11

how are genes turned off and on in cells

Answer 11

The turning on and off of genes in specific cells is controlled by cell specific transcription factors.
Transcription factors bind to regulatory elements called enhancers.
Enhancers influence the stable binding of the transcriptional machinery to the promoter.

Question 12

MyoD

Answer 12

A master regulatory gene

sets up a cascade of turning on all of the genes needed for a muscle cells to become a muscle cell

Question 13

what is the first event in organogenesis

Answer 13

neurulation

Question 14

what is the first event in neurulation

Answer 14

the formation of a rod-like structure of mesoderm cells along the dorsal midline of the ffuture embryo called the notochord

Question 15

what is special about notochord cells

Answer 15

they can induce (send signals to) other
surrounding cells to initiate their differentiation. Signals sent from the notochord to the
overlying ectoderm instruct the ectoderm to thicken and form the neural plate.

Question 16

what happens once the neural plate is formed

Answer 16

it begins to fold upwards, forming neural folds. These neural folds then fuse and enclose an internalised neural tube.

Question 17

Neural plate border

Answer 17

Separates the neural plate from the rest of the ectoderm

Question 18

Neural crest

Answer 18

when the neural plate forms neural folds, the two ends join at what is now referred to as the neural crest.

Question 19

what do neural crest cells form

Answer 19

they differentiate to form most of the peripheral nervous system

Question 20

sonic hedgehog

Answer 20

an important developmental regulatory gene

plays roled in multiple developmental events eg neurulation and limb development

Question 21

Wnt signalling family

Answer 21

The Wnt signaling
family of secreted proteins is present in all Metazoan animals (animals with an organised
body plan) and Wnt family members act in many aspects of development. I

establishing the body plan, limb
development and development of all organs.

Question 22

Wnt1

Answer 22

The Wnt1 gene is one of the 19 genes in
the family and plays an important role in controlling development of the brain and spinal
cord in vertebrate embryos.

Question 23

Pax6

Answer 23

paired box 6, gene encodes
a transcription factor that plays important roles in controlling patterning and development
in different regions of the central nervous system. In particular, Pax6 is known as the
master regulatory gene during eye development in all animals as diverse as vertebrates
and Drosophila.

Question 24

Fgf8

Answer 24

Fgf8 is involved in multiple roles at all stages
of development, including mesoderm formation during gastrulation, spinal cord induction
during neurulation and limb outgrowth.

Question 25

TS19

Answer 25

no retinal pogmentation or signs of fingers