Which of the following is not a concern regarding the use of corn as a biofuel

Astudent drew the following flowchart to show the movement of nutrients. soil → roots → plants →? where does nitrogen go next? a. directly into nearby animals as nutrition b. directly into aquifers through condensation c. directly into the air through evaporation d. directly into nearby plants during fixation

Where do the respiratory and circulatory systems meet? a. in the heart b. in the muscles c. in the lungs d. in the brain

Some substances but not other can cross the (blank) membrane of a cell