Ch 7-8

Question 1

Species

Answer 1

A group of organisms that are closely related and can mate to produce fertile offspring.

Question 2

Evolution

Answer 2

The process in which inherited characteristics within a population change over generations such that new species sometimes arise.

Question 3

Fossils

Answer 3

The trace or remains of an organism that lived long ago, most commonly preserved in sedimentary rock.

Question 4

Fossils record

Answer 4

A historical sequence of life indicated by fossils found in layers of the earths crust.

Question 5

Trait

Answer 5

A genetically determined characteristic.

Question 6

Selective breeding

Answer 6

The human practice of breeding animals or plants that have certain desired traits.

Question 7

Natural selection

Answer 7

The process by which individuals that are better adapted to their environment survive and reproduce more successfully that less well adapted individuals do.

Question 8

Generation time

Answer 8

The period between the birth of one generation and the birth of the next generation.

Question 9

Speciation

Answer 9

The formation of new species as a result of evolution.

Question 10

Adaption

Answer 10

A characteristic that improves an individual’s ability to survive and reproduce in a particular environment.

Question 11

Relative dating

Answer 11

Any method of determining weather an event or object is older or younger than other events or objects.

Question 12

Absolute dating

Answer 12

Any method of measuring the age of an object or event in years.

Question 13

Geologic time scale

Answer 13

The standard method used to divide the Earths long natural history into manageable parts.

Question 14

Extinct

Answer 14

Describes a species that has died out completely.

Question 15

Plate tectonics

Answer 15

The theory that explains how large pieces of the Earths outermost layer, called tectonic plates, move and change shape.

Question 16

Precambrian time

Answer 16

The period in the geologic time scale from the formation of the earth to the beginning of the Paleozoic era, from about 4.6 billion to 542 million years ago.

Question 17

Paleozoic era

Answer 17

The geologic era that followed Precambrian time and that lasted from 542 million to 251 million years ago.

Question 18

Mesozoic era

Answer 18

The geologic era that lasted from 251 million years ago to 65.5 million years ago, also called age of reptiles.

Question 19

Cenozoic era

Answer 19

The most recent geologic era, beginning 65 million years ago, called age of mammals.

Question 20

Primate

Answer 20

A type of mammal characterized by opposable thumbs and binocular vision.

Question 21

Hominid

Answer 21

A type of primate characterized by bipedalism, relatively long lower limbs, and lack of a tail.

Question 22

Homo sapiens

Answer 22

The species of hominids that includes modern humans and their closest ancestors, and that first appeared about 100,000 to 160,000 years ago.