Chapter 4 Vocabulary

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Variation

Back 1

A visible or invisible difference in an organism

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Biological species

Back 2

A group of reproductively compatible populations; meaning that members of these populations can interbreed and produce offspring that are healthy and are themselves able to reproduce successfully.

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Mutations

Back 3

Are changes in the genetic material of an organism

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Selective advantage

Back 4

Characteristic that improves an organism's chance of survival, usually in a changing environment; the result of mutations

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Natural selection

Back 5

A process that results when the characteristics of a population of organisms change because individuals with certain inherited traits survive specific local environmental conditions and, through reproduction, pass on their traits to their offspring

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Neutral mutation

Back 6

Changes in DNA sequence that are neither beneficial nor detrimental to the ability of an organism to survive or reproduce.

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Harmful mutation

Back 7

If a mutation changes a protein produced by a gene, the result is likely to be harmful.

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Beneficial mutation

Back 8

Raw materials that may in time be taken up by natural selection and spread through the population

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Asexual reproduction

Back 9

Reproduction that requires only one parent and does not involve gametes. Produces genetically identical off spring

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Allopatric speciation

Back 10

Biological populations of the same species become isolated from each other to an extent that prevents or interferes with genetic interchange.

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Selective pressure

Back 11

Environmental condition or conditions that select for certain characteristics of individuals, and select against others.

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Theory of evolution by natural selection

Back 12

A well-supported, widely accepted explanation of how species have changed, and continue to change, during Earth's history as a result of natural selection.

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Palaeontology

Back 13

The study of ancient life through the examination of fossils.

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Inheritance of acquired characteristics

Back 14

Theory that characteristics acquired during an organism's lifetime could be passed to its offspring

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Transitional fossils

Back 15

The remains of the impressions of a prehistoric organism that shows intermediary links between groups of organisms and shares characteristics among these groups.

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Fossil record

Back 16

Remains or traces of past life found in sedimentary rock, which reveals the history of life on earth and the kinds of organisms that were alive in the past .

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Biogeography

Back 17

The study of the past and present geographical distribution of species.

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Homologous structures

Back 18

Body parts in different species that have the same evolutionary origin and structural elements but may have a different function.

Hint 18

Human arm, dolphin fin, bat wings

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Analogous structures

Back 19

Body parts in different species that have a similar function but evolved separately.

Hint 19

Insect wings and bird wings

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Embryology

Back 20

The branch of biology that deals with the development of an embryo from fertilization of the ovum to the fetus stage.

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Speciation

Back 21

The formation of new species

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Geographical barrier

Back 22

Feature such as a river or mountain that prohibits interbreeding and results in speciation by physically separating populations.

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Biological barriers

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Factor such as behaviour that keeps species reproductively isolated even when they exist in the same region

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Gradualism

Back 24

In evolution, the theory that change occurs slowly and steadily in a linear fashion, and that large changes occur from through the accumulation of many small changes.

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Punctuated equilibrium

Back 25

Model that suggests that evolutionary history consists of long periods of stasis ( stable equilibrium), punctuated by periods of divergence.

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Radiometric dating

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A technique used to date materials such as rocks or carbon, usually based on comparison between the observed abundance of a naturally occurring radioactive isotope and its decay products, using known decay rates.

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Endemic

Back 27

An infection in a population when that infection is maintained in that population without the need for external inputs

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Endemic

Back 28

An infection in a population when that infection is maintained in that population without the need for external inputs

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DNA

Back 29

A molecule that encodes genetic instructions used in the development and functions of all know living organisms and many viruses.

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Genes

Back 30

The basic unit of heredity; a specific sequence of DNA that encodes a protein , tRNA, rRNA molecule, or regulates the transcription of such sequence; governs the expression of a particular trait and can be passed to an offspring.

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Genes

Back 31

The basic unit of heredity; a specific sequence of DNA that encodes a protein , tRNA, rRNA molecule, or regulates the transcription of such sequence; governs the expression of a particular trait and can be passed to an offspring.

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Artificial selection

Back 32

The process by which humans breed other animals and plants for a particular trait.