During an experiment, if you purposely change the temperature to test a hypothesis, the temperature is called the a. manipulated variable. b. responding variable. c. hypothetical variable. d. dependent variable.

What protects the lining of the stomach from acidic gastric juices?

Veins have a much lower blood pressure than arteries. which of these prevents backflow of blood in veins? a. pressure applied by the heart b. one–way valves in veins c. thin muscular walls of veins

What is one affect on the australian environment due to the introduction of non-native european rabbits? (a) more grass grew in response to the need of the growing population of rabbits. (b) the rabbits balance out the food chain as they became a natural prey to many predators. (c) the rabbits the land by digging, which caused the soil to spread much needed nutrients. (d) the rabbits out-competed other small animals species and caused them to go extinct.