Lecture 3 - Generation of the difference between embryos (1)

Question 1

What is a field within the embryo?

Answer 1

A group of cells that will produce a particular tissue/organ

Question 2

What is a fate map?

Answer 2

A map showing which parts of the embryo will become a certain tissue

Question 3

How are fate maps generated? [4]

Answer 3

• Injection of a certain dye
• Injection of RNA for a marker gene
• Infection with a retrovirus carrying a reporter gene
• Grafting of labelled tissue

Question 4

How can you tell when a cell adopts a particular fate?

Answer 4

• Take cells from one area of the embryo and place them in another
• If they grow to the original cell it means they had committed to original cell type

Question 5

What does commitment mean?

Answer 5

• When a cell is committed to a particular cell type

- CAN change if environment changes

Question 6

What does determination mean?

Answer 6

• When a cell is committed to a particular cell type

- CANNOT change if environment changes

Question 7

What does competence refer to?

Answer 7

The ability of a group of cells to respond to a signal

Question 8

How can we identify the genes that regulate development?

Answer 8

Look at the genes within mutants that affect development

Question 9

What is in situ hybridisation?

Answer 9

• Add probes labelled for a certain gene to fixed embryos

- Shows a colour for cells that contain that gene

Question 10

True or False? They site of gene transcription and protein localisation is always the same.

Answer 10

False

Question 11

How is immunohistochemistry performed?

Answer 11

• Immobilise antigen
• Insert primary antibodies that recognise antigen
• Insert marked secondary antibodies that recognise primary ones