Negative control of the lac operon. 

No lactose; repression. The lacI gene produces repressor, which binds to the operator and blocks RNA polymerase from transcribing the lac genes.

TLS Online TPP Program

#Id: 4753

#Unit 5. Developmental Biology

AB cell in isolation makes only a small fraction of the cell types it would normally make.

TLS Online TPP Program

#Id: 4754

#Unit 5. Developmental Biology

The determination of the P1-derived somatic founder cells (MS, E, C, and D)are autonomous, with cell fates determined by internal cytoplasmic factors SKN-1, PAL-1, and PIE-1

TLS Online TPP Program

#Id: 4755

#Unit 5. Developmental Biology

The SKN-1 protein is a transcription factor that initiates the activation of those genes responsible for forming the pharynx and intestine.

TLS Online TPP Program

#Id: 4756

#Unit 5. Developmental Biology

The SKN-1 protein is a maternally expressed transcription factor that controls the fate of the P1 blastomere(P1🡪EMS 🡪MS), that generates the posterior pharynx.

TLS Online TPP Program

#Id: 4757

#Unit 5. Developmental Biology

Embryos from homozygous skn-1-deficient mothers lack both pharyngeal mesoderm & endoderm derivatives of EMS.

TLS Online TPP Program

#Id: 4758

#Unit 5. Developmental Biology

skn-1-deficient embryos make extra hypodermal (skin) & body wall tissue.