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the image shows an up-close view of a rock.

light colored rock with lighter colored swirls.

which phrase best describes the rock’s texture?

jagged grains
coarse grains
rounded grains
non-banded grains

In the respiration-photosynthesis cycle shown above, what are the products of cellular respiration that belong in box 2?

Juan and carol were studying invertebrates in biology. they knew that segmented or earth worms preferred a dark, moist habitat. during this lab, they would be investigating the responses of organisms called planaria or dugesia tigrina. these were simple flatworms that still had a one-way digestive system and a very simple nervous system. juan and carol placed the planaria in a petri dish containing cool, distilled water that was partially covered with black paper. they shined a light on the dish. next, they removed the paper and placed a small amount of chicken liver at one end of the dish. they added a few large salt crystals to the water. finally, they added drops of hot water to the cool water in the petri dish. their results can be seen in the data table. according to their experiment, all but one conclusion is valid.

Which of the following structures is a double layer of phospholipids with proteins? a: cytoplasm b: cell membrane c: ribosome d: cell wall