1. What are eukarya?
(a) Bacteria that live on clouds.
(b) Carbon-trapping rocks.
(c) Organisms with nucleated cells.
(d) Salt-tolerant single-celled organisms.

2. When the KT meteor that killed the dinosaurs hit Earth, what percentage of life on the planet perished?
(a) 40.
(b) 15.
(c) 95.
(d) 70.

3. The troposphere is the layer of atmosphere:
(a) That is coldest.
(b) Farthest away.
(c) Closest to the ground.
(d) Just above the highest clouds.

4. During the time of the dinosaurs, Earth's magnetic field was:
(a) Same as it is now.
(b) Three times stronger than today.
(c) Fluctuating wildly.
(d) Three times weaker than today.

5. When did the last supervolcano erupt on Earth?
(a) 74,000 years ago.
(b) 9,000 years ago.
(c) 23,000 years ago.
(d) 1,100 years ago.

Short Answer Questions

1. A hundred years before Einstein's math analyses confirmed the existence of atoms, this self-educated scientist suggested everything is made up of tiny, unchangeable particles:

2. According to the author, humans today have 625 percent more what in their bloodstream compared to previous generations?

3. Compared to at sea level, oxygen at a few thousand feet above sea level is:

4. What must amino acids do to become protein?

5. Many scientists suspect that Pluto is just a comet of the:

(see the answer key)

This section contains 203 words
(approx. 1 page at 300 words per page)

View a FREE sample