Question

cacti typically grow in very dry climates with infrequent rainfall. when it does rain, the rain usually only penetrates a few inches into the soil. which adaptation is most likely to help a cactus survive in the dry climate?

• thick xylem tissue to transport sugar
• leaves that have a thin cuticle
• extensive shallow roots that absorb water
• more dermal tissue for food storage

Explanation:

1. Thick xylem transports water, not sugar (phloem does this), so this is incorrect.
2. A thin cuticle would increase water loss, which is bad for dry climates, so this is incorrect.
3. Extensive shallow roots can quickly absorb the small amount of rain that only penetrates the top few inches of soil, which matches the given climate conditions.
4. Dermal tissue is for protection, not food storage (storage is done by parenchyma tissue), so this is incorrect.

Answer:

extensive shallow roots that absorb water