Methods in development(Classical approaches 2)

Question 1

What is grafting?

Answer 1

Moving a piece of a tissue from one embryo to another

Question 2

What is orthotopic grafting?

Answer 2

-This consists of taking one tissue from the embryo and placing it in the same location as the donor cell but in the host cell

Question 3

What is heterotopic grafting?

Answer 3

-This consists of taking one tissue from the embryo and placing it in a different location as the donor cell but in the host cell

Question 4

Where does the neural tube travel along in developing vertebrate embryos?

Answer 4

-Neural tube travels along the dorsal midline of the developing vertebrate embryos

Question 5

What structure is present under the neural tube?

Answer 5

-Under the neural tube, there’s the notochord which is a rod like structure

Question 6

What is the notochord the source of and what is it important for?

Answer 6

-The notochord is the source of signals which have inductive properties and are important to establish the fate of the neurons that derive from the ventral portion of the developing neural tube.

Question 7

What is competence?

Answer 7

-The ability to respond to an inductive signal

Question 8

What is the neural tube competent to?

Answer 8

-The neural tube is competent to respond to the inductive signal released by the notochord

Question 9

What is different potential?

Answer 9

When other parts of the embryo may respond differently to the same inductive signal

Question 10

What is totipotent?

Answer 10

-Can give rise to all tissues(the fertilised egg)

Question 11

What is pluripotent?

Answer 11

-Can give rise to many tissues

Question 12

What happens to cells progressively in terms of potential during development?

Answer 12

-Cells often become progressively more restricted in their potential during development

Question 13

What does restriction in potential depend on?

Answer 13

-Restriction in potential often depends on inductive interactions from neighbouring cells

Question 14

What do vegetal cells eventually form?

Answer 14

-The vegetal cells will eventually form the endoderm

Question 15

What do animal cap cells give rise to?

Answer 15

-The animal cap cells will give rise to ectodermal and mesodermal derivatives

Question 16

What can we grow grafts as?

Answer 16

-We can take grafts of different parts of the embryo and grow them as explants

Question 17

What does most animal region of the animal cap give rise to?

Answer 17

-We can see that the most animal region of the animal cap gives rise to ectoderm

Question 18

What do dorsal cells give rise to?

Answer 18

-Dorsal cells give rise to notochordal muscle derivatives

Question 19

What do ventral cells give rise to?

Answer 19

-Ventral cells give rise to mesenchymal derivatives

Question 20

What do vegetal tissue induce and how does this work?

Answer 20

• Vegetal tissue induces mesoderm in animal cap
  
  • The animal cap cell layer is put on top of the vegetal cells
  • This gives an induced mesodermal tissue

Question 21

What do dorsal vegetal cells induce from animal cap cells?

Answer 21

-Dorsal vegetal cells induce muscle and notochord from animal cap cells

Question 22

What do ventral vegetal cells induce from animal cap cells?

Answer 22

-Ventral vegetal cells induce blood and associated tissue from animal cap cells

Question 23

What is activin and in what way does it work?

Answer 23

-Activin is the mesoderm inducing signal and it works in a concentration dependent way