Choose the stage that best matches the description given. In warm, humid climates, only dry bones would exist at this stage.
Day 1
Day 2
Days 3-17
Days 18-25
Days 26-43
After day 50

after receiving a stimus, the sensory receptors send(s) signals to the appropriate area of the body.  

the must be sensory neurons.  

hope its .

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