Questions on The Ultimate Survivors

The University of Arizona's Desert Laboratory is located at Tumamoc Hill, outside Tucson. Gremer and other experts study the many desert plants growing there.

Kathy Gerst

SCIENCE

Before reading

1.    Acorns grow roots before they grow shoots. Why do you think that is?

2.    Seeds can be stored sometimes for years before being planted to grow. What do you think gives a seed the message to start growing?

During reading

1.    Where is the Sonoran Desert?

2.    How does velvet mesquite find water in the desert?

3.    Describe two ways having animals eat its seeds benefits mesquite.

4.    In the rainy season, what is a pulse?

5.    Why are the first 20 days of a desert seedling’s life so crucial?

6.    Explain the two ways in which creosote can reproduce.

7.    Which more quickly grows deep roots: mesquite or acacia?

8.    What commonly eaten food is a clone?

9.    What effect does the consuming of ACC by bacteria have on plants?

10.  Define “hedging.”

After reading

1.    Would you expect a desert plant with inedible seeds to be more or less likely to hedge its bets when it comes to germination? Explain your answer.

2.    Tumbleweed is a common sight in North America’s desert Southwest. From the ideas expressed in this story, what strategy is the tumbleweed exploiting? What is its purpose?

MATHEMATICS

1.    Just 10 percent to 15 percent of a rabbit tobacco plant’s seeds germinate in any given year. Theoretically, how many years might pass before one of the annual plants germinates, survives to maturity and reproduces?