The most useful range for proteins is above 230 nm, where there are absorptions from aromatic side chains While a very weak absorption maximum of phenylalanine occurs at 257 nm, tyrosineand tryptophan dominate the typical protein spectrum with their absorption maxima at 274 nm and 280 nm, respectively

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#Id: 6125

#Unit 3. Fundamental Processes

Humans have the enzyme hSMUG1, which removes any U residues that occur in single-stranded DNA during replication or transcription.  Two other human DNA glycosylases, TDG and MBD4, remove either U or T residues paired with G, generated by deamination of cytosine or 5-methylcytosine, respectively.

TLS Online TPP Program

#Id: 6708

#Unit 3. Fundamental Processes

Conversion of specific uridine residues to pseudouridine and the addition of methyl groups to the 2′-hydroxyl groups

of specific riboses, that are important for the proper assembly and function of snRNPs in pre-mRNA splicing. 

These modifications occur in Cajal bodies, where they are directed by a class of snoRNA-like guide RNA molecules called scaRNAs (small Cajal body–associated RNAs)

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#Id: 6935

#Unit 8. Inheritance Biology

For an inversion to take place, the chromosome must break in two places.

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#Id: 3807

#Unit 5. Developmental Biology

CMF stimulates gene expression in parallel with PSF, and both signals potentiate cAMP signalling by inducing genes involved in cAMP synthesis and detection

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#Id: 4014

#Unit 7. System Physiology – Animal

Membrane ion channels that play important roles in generation of the action potential:

T (transient) channels 

L (long-lasting) channels Voltage gated potassium ion channel