Elliott grows a sunflower in his greenhouse, and he records the daily growth in mass. The sunflower seems to grow out of nothing, contrary to the Law of Conservation of Mass. However, he forgets that matter can enter and escape plants. What is the sunflower an example of? A. a reactant
B. a closed system
C. an open system
D. a product

Which kind of worm has a closed circulatory system? a planarian b fluke c pinworm d an earthworm

Imagine you are a student in alfred hershey and martha chase's lab in the late 1940's. you are given five test tubes with the e. coli bacteria that were infected with t2 bacteriophage that have been labeled with 32p or 35s. unfortunately, you forgot to label the tubes and are now uncertain which were 32p labeled and which were 35s labeled. you place the contents of each tube in a blender and pulse it for a few seconds to shear off the protein coats from the bacterial outer membranes. you then centrifuge the contents to seperate the protein coats and the bacterial cells. you then check for radioactivity and obtain the results shown below. which tubes contained e. coli infected with the phage labeled with 32p? select all tubes that apply.

Paleontologists have found plant fossils deep within the layers of the north polar region. these leaf fossils have been labeled as to the rock layers they were found in, with the lower numbers being layers close to the earth's surface and higher numbers representing deeper layers. according to the numbers of these four leaf fossils, what might you infer?