Question | Answer |
biogenesis | the theory that living organisms come only from other living organisms |
spontaneous generation | an early and now disapproved theory that living organisms come to life spontaneously from nonliving material |
radiometric dating | 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 |
mass number | the sum of the numbers of protons and neutrons in the nucleus of an atom |
radioactive isotope | an isotope that has an unstable nucleus and that emits radiation |
microsphere | spherical in shape and are composed of many protein molecules that are organized as a membrane |
isotope | an atom that has the same number of protons as the other atoms of the same element do but that has a different number of neutron's |
radioactive decay | the disintegration of an unstable atomic nucleus into 1 or more different nuclides, accompanied by the emission of radiation, the nuclear capture or ejection of electrons, or fission |
half-life | the time required for half of a sample of a radioactive isotope to break down by radioactive decay to form a daughter isotope |
coacervate | a mass of colloidal substances held together by electrostatic attraction |
ribozyme | a type of RNA that can act as an enzyme |
chemosynthesis | the production of carbohydrates through the use of energy from inorganic molecules instead of light |
ozone | a gas molecule that is made up of 3 oxygen atoms |
archaea | prokaryotes that are distinguished from other prokaryotes by differences in their genetics and in the makeup of their cell wall; members of the domain Archaea |
cyanobacteria | a bacterium that can carry out photosynthesis, such as a blue-green alga |
endosymbiosis | a mutually beneficial relationship in which 1 organism lives within another |