Answer:
Plasma membrane is the semi-permeable membrane that allow the movement of some selected particles only against the concentration gradient or along the concentration gradient.
Different substances can be move through the diffusion, active process and passive process. The hydrogen in the vesicle has been moved through the facilitated diffusion. In this process, the hydrogen ions will move along the concentration gradient without the requirement of energy but requires the channel protein for its transport.
Prokaryotic are the cells that dont have a necleus or other important membranes of a cell and eukaryotic are just normal cells i think
The answer is B. Cnidarians
Cnidarian body has no left or right side, only tom and bottom surfaces. If you divide cnidarian a about central point, you will get equal parts. So, cnidarians are radially symmetrical animals. This group includes hydroids, jellyfish, anemones, and corals. In all groups, animals have stinging cells on tips of tentacles. They use them to capture the prey. Their name literally means stinging creatures.