Cleavage of both LexA and UmuD is stimulated by a protein called RecA, which is activated by single-stranded DNA resulting from DNA damage.

TLS Online TPP Program

#Id: 1232

#Unit 7. System Physiology – Animal

In the intestine,

1,25-dihydroxycholecalciferol induces the synthesis of calbindin D-28 K which promotes Ca2+ absorption.

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#Id: 8879

#Unit 2. Cellular Organization

This combination of two positive feedback loops:

one that activates a CDK1 activator (Cdc25C)

one that inhibits a CDK1 inhibitor (Wee1)

results in the abrupt and irreversible transition from G2 into mitosis.

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#Id: 1449

#Unit 4. Cell Communication and Cell Signaling

Gap junctions permit the passage of molecules as large as 1.2 nm in diameter (molecules smaller than 1200 Da).

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#Id: 4780

#Unit 5. Developmental Biology

Wnt pathway is critical in establishing the anterior-posterior axis of C. elegans.

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#Id: 723

#Unit 3. Fundamental Processes

The bacterial DnaA protein is the replication initiator; it binds sequence specifically to multiple sites (dnaA boxes) in oriC.