Answer:
D
Explanation:
Facilitated diffusion is a form of passive transport hence no energy is required by the cell. This means that while the molecules are moving down a concentration gradient – line normal diffusion – the movement of the molecules needs to be facilitated (in this case by a transmembrane protein) either because the molecule is polar and can't pass through the hydrophobic region of the cell membrane, or the molecule is too big to passively pass through the small natural pores of the cell membrane.
Answer:
Since sea urchins are picky, they are used as indicator organisms in public aquariums to determine if the system is functioning properly. This is because they are very "picky" about water quality. If the water is contaminated, the sea urchins will be the first to show signs of stress, spines laying down or falling off. Do use an aquarium filter and do clean up the day after feeding. Any metal exposed to the seawater will corrode and poison the tank. A dying sea urchin will often spawn out and rot out, causing the others in the tank to spawn and die as welll.
Explanation:
bb i need the answers to tell u something
Answer: "photosynthesis" .
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<u>Note</u>: These small, moving "green disks" seen while observing an <em>Elodea</em> plant cell—under a microscrope— are "chloroplasts". The "chloroplasts" are organelles that ar responsible for "photosynthesis" .
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