Many plants have thorns on their stems or leaves. what is the most likely explanation for the evolution of thorns?
a) thorns plants produce more food from photosynthesis.
b) thorns are an example of a mutation that arises in the genetic code of plants.
c) thorns plants to conserve resources like water and soil nutrients that may be used by other organisms.
d) thorns are an adaptation that some plants have evolved in order to discourage herbivores from eating the plant.

1. loamy sand is about 80% sand with 10% clay and defined mostly by sand particles with some clay to provide structure and fertility. the sand particles are easily visible and the soil holds structure but breaks apart easily.

2. scott sand can improve his soil quality by incorporating more silt and organic matter into the soil. peat moss and organic matter can also be incorporated.

only about ten percent of the energy at one trophic level is passed on to organisms at the next trophic level. the remainder of the energy is used in life processes or lost as heat.