Developmental Genetics

Question 1

Morphogen definition

Answer 1

Molecule responsible for determining the pattern of tissue development including the positions of the various specialized cell types within a tissue

Question 2

How morphogens function

Answer 2

Diffuse from production source to form concentration gradient
Interact with signaling pathways that produce a specific gene expression profile dependent on local morphogen concentration

Question 3

Homeobox (HOX) genes

Answer 3

Transcription factors (DNA binding proteins) that activate development of different parts of body
Different HOX genes correspond to different parts of body

Question 4

How HOX gene expression is controlled

Answer 4

Polycomb and trithorax complexes remodel chromatin for gene silencing
Only genes specific to cell type are left on (ex- only skeletal muscle genes are left on in skeletal muscle cells; all others are shut off)

Question 5

Body systems that HOX genes impact

Answer 5

Central nervous system
Axial skeleton
Gastrointestinal tract
Urogenital tract
External genitalia
Limbs