Historically, an important strategy for disrupting the adhesion of integrins to their ligands is by using a synthetic peptide that mimics the binding site on the ecm molecule to which the integrin attaches. in the case of fibronectin, the amino acid sequence is arginine-glycine-aspartate (when written using the single letter designation for each amino acid, this sequence becomes rgd). explain why addition of such synthetic peptides would disrupt binding of cells to their normal substratum.

Birds, bats and humans all have a vertebral column. a) if you group birds, bats and humans in one clade and leave out other apes and mammals, what type of group would they form (monophyletic, paraphyletic, polyphyletic)? explain b) what do we call a trait like presence of vertebral column within bats, birds and humans (synapomorphy (shared derived trait), symplesiomorphy (shared ancestral trait), homoplasy)? explain. c) what other organisms would you have to include in this clade in order to have a monophyletic group?