In the processes of photosynthesis and cellular respiration, carbon is cyc between all major spheres on Earth. Plants obtain carbon dioxide from t
atmosphere as one reactant to conduct photosynthesis. Carbon dioxide
produced by organisms as a result of carrying out cellular respiration.
Which claim is correct about the cycling of matter and the
flow of energy in the carbon cycle?
In an ecosystem, matter cycles and energy flows.
In the ecosystem, matter flows and energy cycles.
In an ecosystem, both matter and energy cycle.
In an ecosystem, both matter and energy flow.

Aresearcher designed an investigation to test what effect eating different types of food would have on blood insulin levels. she selected 10 male subjects who were all 25 years of age and in good health. the experiment took place over 3 days. at 8: 00 a.m. on each day, the subjects ate a meal consisting of only 1 type of food. they had their blood insulin levels measured after consuming the meal. on day 1 they ate a high fat diet, on day 2 they ate a high protein diet, and on day 3 they ate a high sugar diel what is the independent variable in this experiment? a the age of the subjects b the blood insulin level c the type of food consumed d the time of day the meal was consumed