Expression of class II molecules by B cells is down-regulated by IFN- .

TLS Online TPP Program

#Id: 9065

#Unit 4. Cell Communication and Cell Signaling

The promoter or enhancer segments of all genes regulated by PKA contain a cis-acting DNA sequence, the cAMP-response element (CRE), which

contains the highly conserved nucleotide sequence,

5'-TGACGTCA-3'.

TLS Online TPP Program

#Id: 3093

#Unit 3. Fundamental Processes

When cells divide more rapidly than every 60 minutes, a replication cycle is initiated before the end of the preceding division cycle.

TLS Online TPP Program

#Id: 5503

#Unit 10. Ecological Principles

Stress tolerators can survive and reproduce under extreme environmental conditions, such as very low water availability, very cold temperatures, or high salt concentrations.

Ex - Lichen, Mangrove plant, cacti, Deserts animal.

TLS Online TPP Program

#Id: 7900

#Unit 2. Cellular Organization

Leber’s hereditary optic neuropathy

caused by a missense mutation in the mtDNA gene

encoding subunit 4 of the NADH-CoQ reductase

TLS Online TPP Program

#Id: 2739

#Unit 13. Methods in Biology

To measure the activity of a promoter, one can link it to a reporter gene, such as the genes encoding b-galactosidase, CAT, or luciferase, and let 

the easily assayed reporter gene products indicate the activity of the promoter.