WONDER #966: How Does a Cactus Live Without Water?

Question 1 of 3

How many types of cacti are there in the world?

  1. over 2,000
  2. 1 million
  3. 256
  4. over 20,000

Question 2 of 3

The prickly spines of cacti are actually highly-modified what?

  1. defense mechanisms
  2. plant organs
  3. pieces of bark
  4. leaves

Question 3 of 3

If you ever get stranded in the desert, opening up a fully-grown saguaro cactus might provide you with how much water if it has rained recently?

  1. 1 gallon
  2. 40 gallons
  3. up to 200 gallons
  4. over 1,000 gallons

Check your answers online at https://www.wonderopolis.org/wonder/how-does-a-cactus-live-without-water.