Which type of epithelium lines the stomach and intestinal tract?

1) what three conditions must be present for minerals to form through natural processes? 2) why are minerals considered inorganic substances? 3) how do oxides differ from other minerals that contain oxygen atoms? 4) how is a sulfide different from a sulfate? what makes native elements unique?

Substances that can pass through cell membranes by diffusion include a. na ions. b. proteins c. glucose. d. oxygen.

Which of the following describes a bathypelagic zone