Which of the following best describes the matter present in an ecosystem?
A. The total amount of matter in an ecosystem is constantly decreasing due to the process of decomposition
B.
The waste materials generated by one organism are often reused by other organisms
C. When an organism reproduces new matter is added to its ecosystem
D. New matter is continuously generated by an ecosystem in a process known as photosynthesis
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Aneuron is stimulated with an electric pulse. the action potential is detected at a point 3.70 cm down the axon 0.0052 s later.when the action potential is detected 7.20 cm from the point of stimulation, the time required is 0.0063 s. what is the speed of the electric pulse along the axon? (why are two measurements needed instead of only one? )

List charasteristics of athenosphere

Asolution of an enzyme and a substrate was placed in a water bath and the temperature of the reaction was raised gradually. the graph shown was plotted at the end of the experiment. what can be concluded from the graph? a) temperature has no effect on the activity of the enzyme. b) the effect of temperature on the enzyme is unpredictable. c) the enzyme shows increased activity up to a certain temperature. d) the activity of the enzyme is inversely proportional to the temperature.