Useable fresh water comes from many places on Earth. Can you match the source of water with its description?

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.

Which statements about a food chain are true? choose all answers that are correct. a. plants are the first living organisms in food chains on land. b. the plants in a food chain are called herbivores. c. all food chains on land begin with energy from the sun. d. carnivores in a food chain eat only plants.

Which of the following correctly matches an immune system cell with the defense it produces? a. b cells release cytotoxins. b. t cells release cytotoxins. c. b cells absorb antibodies. d. t cells absorb antibodies.