Which of the following statements is not true about G-protein coupled receptors? A. They generally mediate the action of fast acting neurotransmitters.
B. They mediate the action of some hormones.
C. They activate signal proteins called G-proteins.
D. Histamine can act as a ligand for some G-protein coupled receptors.

Which of the following statements about c4 carbon fixation is not true? a c4 carbon fixation is an adaptation for plants exposed to high light intensityb. c4 carbon fixation occurs in more plants than c3 carbon fixation.c c4 carbon fixation is more common in areas of high temperatures than c3 carbon fixation.d. c4 carbon fixation occurs in the inner cells of a leaf rather than the entire leaf.

Hummingbirds drink nectar from flowers, while robins eat plant seeds. what does this reduce?

What happens when water’s salinity increases? mass decreases. freezing point decreases. buoyancy of objects decreases. the amount of dissolved minerals decreases.