Use the plural cacti.
Cacti and succulents store water in special cells in the plants' body for later use. The skin of the cacti has a waxy coating to prevent water loss.
The dew point is the temperature where condensation begins.
When I am thirsty, there is nothing better than a can of Mountain Dew.
Desert tortoises get the majority of their water from the grasses, plants, and cacti that they eat. On mornings with dew, they may get even more, as they eat. When water is available, they will soak and drink, sometimes.
You can use a can to make dew by placing it in a cold area. Then you can take the can out and water droplets will form on the outside of it.
Because they are plants, the roots are used the same way in cacti as in every plant, to take in water for the plant to use.
Cacti are able to store water in their stems during times of rain to use during periods of drought.
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Yes: Prickly Pears, Barrel cacti, Saguaro cacti, Aztekium cacti, and Echinopsis cacti a.k.a the hedgehog cactus
Cacti can survive in deserts because they store water in themselves and use them to grow.