The wilderness act of 1964 established the national wilderness preservation system and in it. Your answer is C
Answer:
Beneficial is fruit ripening
And negative is abscission.
Explanation:
Ethylene is a plant growth regulator or phytohormone of plant. It is beneficial to plants in that it aid fruit ripening, it hasten flower opening and shedding of leaves.
Ethylene also have a negative effect and they include; Ethylene effects include: it result in loss of chlorophyll, abortion of major plants part, it lead to the stem shortening, abscission or dropping of plant parts, epinasty, and dormancy and scinence. Thus hormone can be produced when plants are injured, either mechanically or are affect by certain disease
Pure substances are further broken down into elements and compounds. Mixtures are physically combined structures that can be separated into their original components. Hope this helps!