run something into something. 1. to guide or route something, such as a wire or a pipe, into something or a place. The worker ran the circuit into each room. He ran in the circuit as specified. 2. to guide something into something; to drive or steer something into something else.
A change of color to a blue-black or purple color suggests that starch is present. If there is no change in color, this suggests no starch is detectable. Note the change of the iodine to black on the potato (right) but not the apple (left). (10% Tincture of iodine.) Potato contains starch, but apple does not.
Iodine is an indicator that turns blue-black in the presence of starch. The leaf that was in the light turns blue-black, which demonstrates that the leaf has been performing photosynthesis and producing starch. Try the test again with a variegated leaf (one with both green and white) that has been in the sunlight. A leaf needs chlorophyll to perform photosynthesis â based on that information, where on the variegated leaf do you think you would find starch?