Page 133 - Science Course 3 (Book 2)

Mo11-L4: Vocabulary Review

Direction: Write the correct term in the boxes to the right of each def nition. Then unscramble the letters
from the shaded boxes to spell a ninth term.

eon epoch era extinct geographic isolation
land bridge mass extinction period scale

1. dying out 1.

2. connects continents that previously 2.
had been separated by water

3. occurs when a physical barrier 3.
separates a population from the rest
of its species

4. a subdivision of an eon 4.

5. the longest unit of geologic time 5.

6. a series of marks or points at known 6.
intervals

7. event during which many species die. 7.

8. a subdivision of a period. 8.

9. When they are unscrambled, the letters in the shaded boxes spell ,
which is a subdivision of an era

Mo11-L4: Key Concept Organizer

Direction: On each line, write the term from the word bank that correctly completes each sentence.
Each term is used only once.

epochs eras fossils Mesozoic
Paleozoic periods Phanerozoic Triassic
1. Divisions in the geologic time scale were
developed based on differences in the
in different rock layers.

2. Eons, the longest unit of geologic time,
are subdivided into .

3. Periods are subdivided into .

4. Jurassic and the Ordovician are examples
of geologic .

5. The Cretaceous period is part of the
era.
6. The Cambrian period is part of the
era.
7. The Mesozoic era includes the
period.
125