The Cactus and the Rain
Written by Studio AM.
Your result
- Words per minute
- Score
- Pace
Words per minute mean something only with the score beside them. They describe this passage on this read. With fewer than 3 right, try the next slower pace.
Choose a pace and select Start. The passage is paced and timed, then the questions check what you understood. How pace mode works
Reading time 0:00
The saguaro is the tall cactus of the Sonoran Desert, in the southwestern United States and northwestern Mexico. Long dry periods make rain a valuable resource. During those periods, rain is rare, and water near the surface can disappear quickly.
Many of the saguaro's roots are shallow and spread widely around it. When rain wets the surface soil, this network can absorb water across a large area. The cactus also has a deeper root that helps anchor it.
The stem has folds like an accordion. As it stores water, these folds allow the stem to expand. During dry periods, the plant uses its stored water and the stem can shrink. A large saguaro containing plenty of water can weigh several tons.
Growth is much slower than water collection. A young saguaro may be only a few centimetres tall after several years. Arms often appear after decades, but timing varies with growing conditions. Some plants live more than a hundred and fifty years. Wide roots and a flexible stem help this long-lived cactus cope with an uneven supply of rain.
The passage is hidden while you answer. It comes back with your result.
Questions
Choose an answer. The explanation appears after you answer.
-
Question 1 of 4
Which sentence best states the main idea?
The answer is C: The saguaro's roots and expanding stem help it collect and store water between rains.
The passage connects the roots' wide reach with the stem's ability to expand and store water for dry periods.
-
Question 2 of 4
What does the passage say about many of the saguaro's roots?
The answer is A: They spread widely near the surface.
Many roots spread widely just below the surface, where they can absorb rainwater.
-
Question 3 of 4
Why are shallow roots an advantage for this cactus?
The answer is D: They can absorb rainwater before the surface soil dries.
Rainwater near the surface can disappear quickly. Shallow roots let the cactus use it while it is available.
-
Question 4 of 4
In this passage, "rare" means
The answer is B: not happening often
'Rare' describes rain during the long dry periods: it does not happen often.
Score: none answered yet.