There are two classes of snoRNPs involved in rRNA processing in nucleolus.  The box H/ACA snoRNPs are involved in pseudouridylylation, and box C/D snoRNPs function in 2-O-methylations.

TLS Online TPP Program

#Id: 2425

#Unit 3. Fundamental Processes

There are other parallels between initiation and termination. Both require breaking of hydrogen bonds (initial melting of DNA at initiation and RNA–DNA dissociation at termination), and both can utilize additional proteins (sigma factors, activators, repressors, and rho factor) that interact with the core enzyme.

TLS Online TPP Program

#Id: 3092

#Unit 3. Fundamental Processes

A fixed time of40 minutes is required to replicate the E. coli chromosome, and an additional 20 minutes is required before the cell can divide.

TLS Online TPP Program

#Id: 9916

#Unit 4. Cell Communication and Cell Signaling

Viral Infections

Virus enters a cell via a cell-surface receptor for which it has affinity and preempts cell biosynthetic machinery to replicate all components of itself, including its genome.

This genome replication step is often error prone, generating numerous mutations.

TLS Online TPP Program

#Id: 7501

#Unit 4. Cell Communication and Cell Signaling

Site of DNA cleavage - Recombination Signal Sequence (RSS) 

TLS Online TPP Program

#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).