4. In a given park area, there are two tertiary consumers whose combined mass is 500 kg. a) What would be the approximate mass of secondary consumers needed to support
these tertiary consumers?
b) What would be the approximate mass of the primary consumers in this food chain?
c) What would be the approximate mass of plant material needed to support the food
chain?

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.

Diego conducted an experiment to find out what kind of ball bounces the highest when dropped from a five-foot platform. he used a golf ball, a tennis ball, and a soccer ball. he dropped each ball from the balcony once. diego recorded his observations after each drop. what can diego do to best improve the reliability of his results? a) drop each ball from the platform three more times b) record his observations in more than one unit c) write at least two scientific questions after the experiment is complete d) share his results with other people who have done similar experiments you for the !

Which term describes a normal value for something in the body? a. homeostasis b. set point c. feedback loop d. integration center