Movement of molecular oxygen (O2) and carbon dioxide (CO2) across the cell membrane Choose one: A. occurs only unidirectionally, such that oxygen is allowed to enter and carbon dioxide (waste) is able to leave. B. only occurs when the O and C atoms are part of some other molecule (e. g., a sugar or amino acid). C. requires energy in the form of ATP or the proton motive force. D. occurs passively, but membrane transporters are required to facilitate their movement. E. occurs by passive diffusion.

C

Explanation:

Lipids and carbohydrates are dissimilar in that

what statement best describes the difference between the sympathetic and parasympathetic nervous systems?

the sympathetic nervous system prepares the body for intense physical activity and is often referred to as the fight-or-flight response. the parasympathetic nervous system has almost the exact opposite effect and relaxes the body and inhibits or slows many high energy functions.

igneous rocks which formed by the crystallization of magma at the surface of the earth called extrusive rocks. they are characterized by fine-grained textures because the rapid cooling at or near the surface did not provide enough time for large crystals to grow.