Question

After studying about recycling, members of John’s biology class investigated the effect of various recycled products on plant growth. John's lab group compared the effect of different aged grass compost on bean plants. Because decomposition is necessary for the release of nutrients, the group hypothesized that older grass compost would produce taller bean plants. Three flats of bean plants were grown for five days. The plants were then fertilized as follows: (a) Flat A: 450g of 3 month old compost, (b) Flat B: 450 g of 6 month old compost, (c) Flat C: 0g compost. The plants received the same amount of sunlight and water each day. At the end of 30 days the group recorded the height of the plants (cm).

Question:
Dependent variable:
Independent variable:
Constants:
Hypothesis:

Answer 1

Dependent Variable: Height of the plants (cm)

Independent Variable: amount of recycled (old) grass mulch

Constants: Sunlight, water, time

Hypothesis: The older the grass mulch, the taller the plants will grow, as it releases more nutrients when decomposing.

Step-by-step explanation:

Easy