What is a specialized form of diffusion

As , plants meet their needs for making food from air, soil, water, and the sun's energy in a process called there are plants called grow high in trees without here are words to put in the blanks. 1.) producers 2.) consumers 3.) chloroplasts 4.) epiphytes

There are six elements that make up most of the human body. which of the following is not one of these six elements?

Which of these serves as a reference for comparison during a scientific investigation? a)outcome variable (dependent variable) b) test variable (independent variable) c)control group d)hypothesis