TLS Online TPP Program

#Id: 7224

#Unit 5. Developmental Biology

Two distinct selection processes are required

Positive selection, which selects for those thymocytes bearing receptors capable of binding self-MHC molecules, resulting in MHC restriction

Negative selection, which selects against thymocytes bearing high-affinity receptors for self-MHC/peptide complexes, resulting in self-tolerance.

TLS Online TPP Program

#Id: 6673

#Unit 3. Fundamental Processes

Splice sites are directional in nature. 5’ splice site -the left, or donor, site and the 3’ splice site - right, or acceptor, site

TLS Online TPP Program

#Id: 6002

#Unit 3. Fundamental Processes

ORC was first found in S. cerevisiae (where it may be called scORC), but similar complexes have now been characterized in Schizosaccharomyces pombe (spORC), Drosophila (DmORC), and Xenopus (XlORC). All of the ORC complexes bind to DNA.

TLS Online TPP Program

#Id: 590

#Unit 2. Cellular Organization

Virulent phage replicate and kill their host by lysing but Temperate phage such as l, infect cells but don’t necessarily kill.

TLS Online TPP Program

#Id: 2592

#Unit 13. Methods in Biology

The logic for hotstart PCR is as follows, most DNA samples used as template will have some single-stranded DNA.