Describe examples of allopatric radiation in the madagascar-india landmasses and dusky salamanders.

During Pangea, Madagascar and India were one landmass. The species of frogs were homogenous across the landmass. However, after continental drift that began approximately 88 years ago, allopatric speciation occurred to form different species on the two continents.

The dusky salamanders on the two continents that could once reproduce viable offspring 88 years ago, cannot reproduce viably today because they have diverged into two different species now.

enzyme active site and substrate specificity

enzymes bind with chemical reactants called substrates. there may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. in some reactions, a single-reactant substrate is broken down into multiple products