There are four known forces that are involved in evolution:

1)mutation,

2) genetic drift

3) gene flow or migration

4) selection.

TLS Online TPP Program

#Id: 7415

#Unit 5. Developmental Biology

The homologue of TGF-β in Drosophila is Dpp.

TLS Online TPP Program

#Id: 7416

#Unit 5. Developmental Biology

Two regions of Drosophila chromosome III contain most of homeotic genes: Antennapedia complex Bithorax complex

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#Id: 7417

#Unit 5. Developmental Biology

Antennapedia complex, contains the homeotic genes: Labial (lab)

Antennapedia (Antp)

Sex combs reduced (scr), Deformed (dfd) 

Proboscipedia (pb)

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#Id: 7418

#Unit 5. Developmental Biology

Three protein-coding genes are found in bithorax complex: 

Ultrabithorax (Ubx)

Abdominal A (abdA) 

Abdominal B (AbdB) 

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#Id: 7419

#Unit 5. Developmental Biology

Ultrabithorax (Ubx), is required for the identity of the third thoracic segment.

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#Id: 7420

#Unit 5. Developmental Biology

one of Antennapedia’s functions is to repress the genes that would trigger antenna and eye development.