Origin Of Life - Chapter 21

Front 1

acquired characteristics

Back 1

acquired characteristics are learned behaviors not genetically determined and cannot be passed on to future generations

Front 2

autotroph

Back 2

an autotroph is an organism that is able to make its food molecules from inorganic raw material by using basic energy sources such as sunlight

Front 3

biogenesis

Back 3

biogenesis defines the concept that life originates only from preexisting life

Front 4

domains

Back 4

domains is defined as a classification group above that of kingdoms

Front 5

endosymbiotic theory

Back 5

an endosymbiotic theory means a theory suggesting that some organelles found in eukaryotic cells may have originated as free-living prokaryotes

Front 6

evolution

Back 6

evolution is the continuous genetic adaptation of a population of organisms to its environment over time

Front 7

gene flow

Back 7

gene flow can be defined as: the movement of genes from one generation to another or from one place to another

Front 8

gene pool

Back 8

a gene pool: all of the genes of a population of organisms

Front 9

genetic recombination

Back 9

genetic recombination is the gene mixing that occurs as a result of sexual reproduction

Front 10

geographic barriers

Back 10

geographic barriers are geographic features that keep different potions of a species from exchanging genes

Front 11

geographic isolation

Back 11

geographic isolation is a condition in which part of the gene pool is separated by geographic barriers from the rest of the population

Front 12

Hardy-Weinberg concept

Back 12

Hardy Weinberg concept is the notion that population must be infinitely large, have random mating, no mutations, no migrations and no selection for specific characteristics in order to prevent evolution from taking place

Front 13

heterotroph

Back 13

hetertroph an organism that requires a source of organic material from its environment; it cannot produce its own food

Front 14

morphological species concept

Back 14

morphological species concept means: species can be distinguished from one another by structural characeristics

Front 15

mutation

Back 15

mutation is any and or all changes in the genetic information of a cell

Front 16

natural selection

Back 16

natural selection is the process that encourage the passage of beneficial genes and discourage the passage of harmful or unfavorable genes from one generation to the next

Front 17

oxidizing atmosphere

Back 17

oxidizing atmosphere an atmosphere that contains molecular oxygen

Front 18

range

Back 18

range is the geographical distribution of a species

Front 19

selecting agents

Back 19

selecting agents are specific environmental factors that favor the passage of certain characteristics from one generation to the next and discourage others

Front 20

speciation

Back 20

speciation is the process of generating new species

Front 21

species

Back 21

species means a group of organisms that can interbreed naturally to produce fertile offspring

Front 22

spontaneous generation

Back 22

spontaneous generation is the theory that living organisms arose from non-living material

Front 23

spontaneous mutation

Back 23

spontaneous mutation a change in the DNA of an organism for which there is no known cause

Front 24

subspecies

Back 24

subspecies is a regional group or groups within a species which are significantly different structurally, physiologically or behaviorally yet are capable of exchanging genes by interbreeding with other members of the species

Front 25

theory of natural selection

Back 25

theory of natural selection is the idea that some individuals within a population will have favorable combination of genes that make it very likely that those individuals will survive, reproduce and pass their genes to the next generation