Some plants like poison ivy and poison oak produce an oil that causes serious rashes in some animals, the oil is advantageous as a?
a. support system
b. defense mechanism
c. nutritional process
d. ability to change

Which of the following describe the role a biochemical pump plays in active transport? a it prevents water from moving across the cell membrane. b it uses energy to move materials across the cell membrane against the concentration gradient. c it large molecules cross the cell membrane without using energy. d it a cell move molecules from an area of higher concentration to an area of lower concentration.