Determine whether each statement is true (T) or false (F). Place your answer in the
blank space given.
a. F. W. Went isolated the chemical substance responsible for
communicating stimulus information.
b. The chemical substance responsible for communicating stimulus
information is a hormone.
c. Charles and Francis Darwin confirmed that the tip of a plant stem is
responsible for initiating the phototropic response.
d. When the tip of a stem is covered with a transparent cap, the stem bends
toward the light source anyway.
e. When the base of a stem is covered with an opaque shield, the stem
bends away from the light source.
f. An example of another control mechanism is that some plants require
more than 12 hours of darkness to produce flowers.