Chapter 16

Question 1

Radiometric Dating

Answer 1

the use of radioactive isotopes as a measure for determining the age of a rock or fossil

Question 2

Radioactive Isotope

Answer 2

an unstable form of an element that decays into another element by radiation - that is, by emitting energetic particles

Question 3

Half-life

Answer 3

the time it takes for one-half of a sample of a radioactive isotope to decay

Question 4

Sedimentary Rock

Answer 4

rock formed from the compression of layers of particles eroded from other rocks

Question 5

Ingenious rock

Answer 5

Rock formed by the cooling and hardening of molten lava

Question 6

Extinction

Answer 6

elimination of all individuals in a species; may occur over time or in a sudden mass die-off

Question 7

Adaptive Radiation

Answer 7

spreading and diversification of organisms that occur when the organisms colonize a new habitat

Question 8

Mass Extinction

Answer 8

extinction between 50% + 90% of all living species that occur relatively rapidly

Question 9

Biogeography

Answer 9

the study of distribution of organisms in geographic space

Question 10

Continental Drift

Answer 10

movement of the continents relative to one another over time

Question 11

Plate Tectonics

Answer 11

theory that the continents are part of large sections that sit atop the Earth’s mantle and that move around and collide due to heart convection currents in the underlying mantle

Question 12

Convergent Evolution

Answer 12

process by which organisms that are not closely related evolve similar adaptations as a result of independent episodes of natural selection

Question 13

Taxonomy

Answer 13

the identification, naming, and classification of organisms on the basis of shared traits

Question 14

9 Categories of Taxonomy

Answer 14

domain, supergroup, kingdom, phylum, class, order, family, genus, species

Question 15

Vertebrates

Answer 15

animals with a rigid backbone

Question 16

Mammals

Answer 16

members of the class Mammalia; all members of this class have mammary glands and a body covered with hair

Question 17

Phylogeny

Answer 17

evolutionary history of a group of organisms

Question 18

Phylogenetic Tree

Answer 18

a branching diagram of relationships showing common ancestry

Question 19

Domain

Answer 19

Highest (most inclusive) category in the modern system of classification

Question 20

3 Domains of Classification

Answer 20

Bacteria, Archaea, and Eukarya