Which has more stomata a desert cactus or a water lily?

its a question given to us by our teacher. please leave an explanation do that I can understand =P

Which has more stomata a desert cactus or a water lily?
Water lilies will have less. Water plants have stomata on the sides exposed to air. Or if totally submerged, there are no stomata present. A cactus is covered with stomata but not as much as average plants.





Here's an exerpt from Radboud University---


Floating waterplants


Plants with floating leaves liek the water lily (Nymphaea sp.) obviously do not lack water. Their stomata of importance for the exchange of gases are present at the top only. Large air cavities provide buoyancy for the leaf. The large intercellular spaces continue into the stem and root and they provide the necessary oxygen to these organs. Leaves floating on a water surface are exposed to the sun and therefore often show a thick cuticle to avoid radiation damage. The species can capture the ample sunlight thanks to their well-developed palisade parenchyma that contains many chloroplasts.





I double checked wiki too.
Reply:I think the desert cactus has more stomata. The land plants need more stomata to survive than the water lily.
Reply:A water lily will have more stomata.A desert cactus will have very few stomata, because in deserts plants face water shortage so in order to avoid loss of water cacti have adapted to the desert environment by possessing few stomata.
Reply:A water lily would have more stomata because it doesn't have to worry about losing water - which is in constant supply for a water lily.


Stomata are the primary way of water evaporation from a plant, so it makes sense a cactus has fewer - it has to retain all the water it possibly can to make it in the dry desert!
Reply:Water lily. Since it is in a pond most of the time, it would have more stomata because it has an abundance of water available, whereas you have the cactus, with less stomata, in the middle of the desert with no water around and it needs to hold on to as much as it can.