The niche employs a variety of mechanisms of cell-to-cell communication to regulate the quiescent, proliferative, and differentiative states of the resident stem cell.

TLS Online TPP Program

#Id: 8485

#Unit 1. Molecules and their Interaction Relevant to Biology

Peptide bonds formed between Xaa and proline (Xaa is any amino acid) the cis to trans ratio is 1:4.

TLS Online TPP Program

#Id: 8486

#Unit 1. Molecules and their Interaction Relevant to Biology

All three kinds of bonds (N-Ca, Ca-Co, and the Co-N peptide bond) are single bonds.

TLS Online TPP Program

#Id: 8487

#Unit 1. Molecules and their Interaction Relevant to Biology

Co and N atoms of the peptide grouping are both in planar sp2 hybridization and the Co and O atoms are linked by a p bond, leaving the nitrogen with a lone pair of electrons in a 2p orbital.

TLS Online TPP Program

#Id: 8488

#Unit 1. Molecules and their Interaction Relevant to Biology

TLS Online TPP Program

#Id: 8489

#Unit 1. Molecules and their Interaction Relevant to Biology

TLS Online TPP Program

#Id: 8490

#Unit 1. Molecules and their Interaction Relevant to Biology

The coplanar relationship of the atoms in the amide group is highlighted as an imaginary

shaded plane lying between two successive a-carbon atoms in the peptide backbone.