Which of the following is the most important environmental clue in changing a seed from being dormant to active growth?
a. water
b. light
c. temperature
d. damage to the seed coat

Astudent poured a solution of bromothymol blue indicator into three test tubes. then he placed an aquatic plant in two of the test tubes, as shown below. he placed a stopper on each test tube and placed them all in the dark for 24 hours. bromothymol blue turns from blue to yellow in the presence of co2