Ch9 - Gap Genes

Question 1

Hunchback forms

Answer 1

a gradient high to low

Question 2

Transcription of anterior gap genes is initiated by

Answer 2

different concentrations of hunchback and bicoid genes
• high hunchback - express giant, prevent transcription of posterior gap genes
• hunchback concentration declines - Kruppel

Question 3

Gradient of … activates abdominal genes

Answer 3

caudal

• high at posterior

Question 4

Gap gene activation

Answer 4

anterior = hunchback --> kruppel
posterior = caudal (abdominal)

Question 5

The expression of gap genes is maintained by

Answer 5

interactions between different gap gene products

Question 6

Boundaries of gap gene transcription

Answer 6

by mutual repression

Question 7

All 4 major gap genes encode

Answer 7

DNA binding proteins that activate/repress the transcription of other gap genes