Narrator: Listen to part of a lecture in an environmental science class. Professor: Today we're going to talk about a fascinating adaptation in desert plants, specifically the saguaro cactus. The saguaro, which is native to the Sonoran Desert, has evolved several strategies to survive extreme heat and drought. First, its accordion-like pleats allow it to expand and contract as it stores and uses water. After a heavy rain, the saguaro can absorb hundreds of gallons of water, swelling to accommodate the liquid. During dry periods, it slowly uses this stored water, and the pleats shrink. Another key adaptation is its shallow, widespread root system. These roots extend far from the plant, sometimes as far as the cactus is tall, to capture moisture from even light rainfalls. Additionally, the saguaro has a thick, waxy coating on its skin that reduces water loss through evaporation. Finally, its growth pattern is slow but steady; a saguaro may only grow a few inches in its first decade. This slow growth allows it to allocate energy efficiently, ensuring survival in a resource-limited environment. So, these combined features make the saguaro a superb example of desert adaptation.
❓ Вопрос What does the professor mention as a function of the saguaro's accordion-like pleats?
A. A) To protect the cactus from herbivores
B. B) To allow the cactus to expand and contract with water storage
C. C) To help the cactus photosynthesize more efficiently
D. D) To reduce the impact of strong desert winds
✅ Правильный ответ
B) To allow the cactus to expand and contract with water storage
TOEFL Listening Tips
Skim the questions first to predict the content
Watch for signal words in lectures and conversations (however, actually, in fact)
For main idea questions, focus on the beginning; for detail questions, focus on examples and data
For attitude questions, pay attention to the speaker's tone and word choice
Take notes on keywords; don't try to write down every word
