What is true of matter in ecosystems?
a. the primary productivity of an ecosystem does not depend on the availability of nutrients.
b. living things can recycle elements within an ecosystem as long as decomposers are present.
c. matter flows in a one-way direction with a 10% loss at each move up in trophic level.
d. elements continuously cycle between the physical environment and living organisms.

What was dr. willem johan kolff’s first step in using the scientific process to invent the hemodialysis machine? he built the machine and tried it with various patients, collecting data about its effectiveness. when a patient’s kidneys failed, he wondered if it would be possible to perform kidney functions with an external machine. he researched and collected data about numerous patients who exhibited symptoms of kidney failure. he drew conclusions from studies of various symptoms of kidney failure, and drew a design for the ideal external blood-processing machine.

What in scientific term why the salty popcorn causes this thirst

How would you describe the the organisms in the second row of model 1 that are connected to the parents by a line