you can put a needle through it and it won't break.
SUBSTANCE: Material composed of only one kind of matter throughout (same atoms or same molecules) ELEMENT: A substance that cannot be decomposed (broken down) into simpler substances by ordinary chemical means. Examples: gold, iron, carbon, hydrogen, oxygen, nitrogen.
Heterotrophs help in maintaining a balance in the ecosystem by providing organic compounds for autotrophs. Certain heterotrophs such as fungi help in reducing decomposed plant and animal material. This recycling activity is important in reducing waste in the environment.
I think *
I think the correct answer from the choices listed above is option B. A modification of the leaves into the spine in a cactus plant can be seen The spines are modified leaves. It helps defend the plant and also reduce the surface area which helps limit loss of water.