Vocabulary Vocabulary ReviewReview

Ch 14 – History Ch 14 – History of Lifeof Life

The scientific principle that

living organisms come only from

other living organisms

Biogenesis

An early and now disproved theory

that living organisms come to life spontaneously

from nonliving material

Spontaneous generation

A method of determining the

absolute age of an object by comparing

the relative percentages of a

radioactive (parent) isotope and a stable (daughter) isotope

Radiometric dating

An atom that has the same number of protons

(or the same atomic number) as other atoms of the same element do but that has a different

number of neutrons (and thus a different atomic

mass)

Isotope

The sum of the numbers of protons and

neutrons in the nucleus of an atom

Mass number

The disintegration of an unstable atomic nucleus

into one or more different nuclides, accompanied by the emission of radiation,

the nuclear capture or ejection of electrons, or

fission

Radioactive decay

An isotope that has an unstable nucleus and that emits radiation

Radioactive isotope

The time required for half of a sample of a

radioactive isotope to break down by

radioactive decay to form a daughter

isotope

Half-life

A microscopic spherical structure composed of many protein molecules that are organized

as a membrane

Microsphere

A mass of droplets of colloidal substances, such as lipids, amino

acids, and sugars, that are held together by

electrostatic attraction

Coacervate

A type of RNA that can act as an

enzyme

Ribozyme

Prokaryotes, most of which are known to live in

extreme environments; differentiated from other prokaryotes by genetic

differences and differences in the make

up of their cell walls

Archaea

The production of carbohydrates

through the use of energy from

inorganic molecules instead

of lightChemosynthesi

s

A group of bacteria that can

carry out photosynthesis

Cyanobacteria

A gas molecule that is made up of

three oxygen atoms

Ozone

A mutually beneficial relationship in which one organism lives within another; a

theory that eukaryotic cells originated

through endosymbiotic relationships between

ancient prokaryotic cellsEndosymbiosis