SOS response in E. coli: 

The LexA protein is the repressor in this system, which has an operator site near each gene. Because the RecA gene is not entirely repressed by the LexA repressor, the normal cell contains about 1,000 RecA monomers. 

TLS Online TPP Program

#Id: 2275

#Unit 3. Fundamental Processes

The subunits of RNA Polymerases

TLS Online TPP Program

#Id: 9947

#Unit 4. Cell Communication and Cell Signaling

The gametes fuse to form a zygote that differentiates to the sporozoite stage within the salivary gland of the mosquito.

TLS Online TPP Program

#Id: 9094

#Unit 4. Cell Communication and Cell Signaling

Phospholipase C cleaves a phospholipid known as PI(4,5) P2, generating two second messengers: 

diffusible IP3 and membrane-bound DAG

TLS Online TPP Program

#Id: 8556

#Unit 1. Molecules and their Interaction Relevant to Biology

The simplest forms of competitive inhibition considered are sometimes termed linear competitive inhibition because both primary and secondary plots are linear. 

TLS Online TPP Program

#Id: 353

#Unit 1. Molecules and their Interaction Relevant to Biology

Transketolase requires the cofactor thiamine pyrophosphate (TPP)