Download Classification of Living Things Glossary

CyberEd® Multimedia Courseware: Classification of Living Things
Classification of Living Things Glossary
aerobic: organisms or processes requiring the presence of oxygen.
Animalia: one of the five broad kingdoms of life in the five -kingdom
classificationscheme. All members of kingdom Animalia are heterotrophic
multicellulareukaryotes.
archaea: single celled prokaryotic organisms that share similarities with other
prokaryotic organisms, such as bacteria, as well as with eukaryotic organisms.
Some taxonomists place archaea in the kingdom Monera, while others assign
them to their own kingdom or domain.
archaebacteria: another name for archaea. Archaebacteria is also a kindgom
under the six-plus-kingdom classification scheme.
asexual reproduction: reproduction where offspring are produced from only one
parent; offspring are genetically identical to their parent.
asymmetrical: lacking a recognizable pattern of symmetry.
autotroph: an organism that produces its own nourishment through
photosynthesis or other processes.
bacteria: prokaryotic unicellular organisms.
bilateral symmetry: pattern of symmetry where an organism displays a distinct
right and left side.
binomial nomenclature: a system of naming organisms developed by Carolus
Linnaeus. Each organism is assigned a two part name composed of the genus
and specific epithet.
cell wall: a rigid structure that can be composed of various substances,
surrounding individual plant and fungi cells.
chloroplast: cellular structure where photosynthesis takes place in eukaryotes.
clade: group of organisms composed of a common ancestor and all its
descendants.
cladistics: a school of systematics where classification of organisms is based on
shared common ancestry.
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CyberEd® Multimedia Courseware: Classification of Living Things
cladogram: a diagram used to visually represent cladistic data. Organisms are
grouped in a cladogram on the basis of synapomorphies, or shared derived
characteristics.
class: a taxonomic grouping narrower than phylum and broader than order.
coccus, (pl) cocci: a round or spherical shaped bacterium.
coelom: specially lined body cavity where internal organs are located. Found in
some animals.
common ancestry: descent from a shared, or common, ancestor.
cyanobacteria: unicellular prokaryotes that carry out photosynthesis, also known
as blue-green algae.
cytoplasm: the contents of a cell between the nuclear envelope and the cell
membrane.
dichotomous key: a tool designed to assist in the classification of organisms.
Consists of a series of divergent choices.
DNA: the double stranded helix shaped macro-molecule that carries hereditary
information from generation to generation.
DNA hybridization: an experiment where single strands of DNA from two
different organisms are combined and allowed to reform double strands. The
degree of bonding indicates the degree of similarity between the different
strands.
domain: taxonomic grouping recognized by some biologists as existing above
the kingdom level.
electron microscope: a device that uses a beam of electrons to form images of
objects.
electron microscopy: the use of an electron microscope to view organisms or
details of organisms not visible to the naked eye.
embryology: the study of the early development of organisms.
embryo: a multicellular organism in the early stages of prenatal development.
empire: another name for domain.
eubacteria: "true" bacteria, as distinguished from archaebacteria.
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CyberEd® Multimedia Courseware: Classification of Living Things
eukaryotic: possessing a membrane bound nucleus in which genetic information
is stored.
evolution: change over time. Evolution in populations can give rise to new
species.
extremophile: an organism that can survive in extreme conditions such as high
heat, high acidity, or high salt concentrations.
family: a taxonomic grouping narrower than order and broader than genus.
filament: long cellular structure containing more than one nucleus in fungi and
water molds.
fitness: in biological terms, a measure of an organism's overall ability to survive
and reproduce.
five-kingdom classification scheme: an assignment of organisms into one of
five broad kingdoms, Monera, Protista, Fungi, Plantae, or Animalia.
fossil record: preserved remains of organisms as they relate to the history of life
on this planet.
Fungi: one of the five broad kingdoms of life in the five-kingdom classification
scheme. Most members of kingdom Fungi are multicellular; all are eukaryotic,
and most are saprotrophs.
gamete: the reproductive cells of an organism; sperm and egg cells.
genetic analysis: the study of DNA and RNA composition.
genus: a taxonomic grouping narrower than family and broader than species.
helical: possessing a spiral shape.
heterotroph: an organism that does not produce its own nourishment through
photosynthesis or other means. Heterotrophic organisms rely on external food
sources.
hierarchical classification scheme: system of taxonomic groupings devised by
Linnaeus, consisting of kingdom, phylum, class, order, family, genus, and
species. The taxonomic grouping family was not utilized by Linnaeus, but was
added later.
invertebrate: organism that lacks a backbone.
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CyberEd® Multimedia Courseware: Classification of Living Things
kingdom: the broadest, most inclusive taxonomic grouping in the five and sixkingdomclassification schemes.
light microscope: an optical device used to view organisms or details of
organisms not visible to the naked eye.
light microscopy: the process of employing optical devices to view organisms
or details of organisms not visible to the naked eye.
Monera: one of the five broad kingdoms of life in the five -kingdom classification
scheme. All members of kingdom Monera are single-celled and prokaryotic.
monophyletic group: in cladistics, a group of organisms composed of a
common ancestor and all its descendants.
morphology: the study of form or structure.
multicellular: composed of more than one cell. Most members of Kingdom
Fungi are multicellular, and all members of Plantae and Animalia are
multicellular.
mutation: changes or variations in a DNA sequence.
nonvascular plant: plant that lack vascular tissue.
nucleoid region: area in the cytoplasm of prokaryotes where DNA is located.
numerical phenetics: also known as phenetics, the school of systematics where
classifications are based solely on the number of traits shared by organisms.
Phenetics does not take into account common ancestry.
obligate anaerobe: an organism that cannot survive in the presence of oxygen.
order: a taxonomic grouping narrower than class and broader than family.
parasite: an organism that obtains its nourishment from a living host organism.
phenetics: Also known as numerical phenetics. The school of systematics where
classifications are based on the number of traits shared by organisms. Phenetics
does not take into account common ancestry.
phenogram: a type of phylogenetic tree used to visually represent phenetic data.
Organisms are grouped in a phenogram according to the number of character
traits they share.
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CyberEd® Multimedia Courseware: Classification of Living Things
phloem: vascular tissue found in some plants that transports nutrients from one
part of the plant to another.
photosynthesis: the process through which plants and some members of the
kingdoms monera and protista utilize solar energy to produce their own
nourishment in the form of sugars from carbon dioxide and water.
phylogenetic tree: branching diagram used to represent phylogeny.
phylogeny: the study of the evolutionary relationships of organisms.
phylum: a taxonomic grouping narrower than kingdom and broader than class.
Plantae: one of the five broad kingdoms of life in the five -kingdom classification
scheme. All members of kingdom Plantae are autotrophic, multicellular
eukaryotes.
plasma membrane: membrane that surrounds an entire cell and which regulates
the flow of substances to and from the cell.
prenatal: prior to birth.
prokaryotic: an organism lacking a membrane bound nucleus in which
geneticinformation is stored.
Protista: one of the five broad kingdoms of life in the five -kingdom classification
scheme, comprised of algae, protozoa, slime molds, and water molds. All
members of kingdom Protista are eukaryotic.
radial symmetry: pattern of symmetry where an organism can be split in half by
any line bisecting the vertical axis
ribosome: cellular structure involved in protein synthesis. Ribosomes contain
genetic material in the form of RNA, and the analysis of this RNA led to the
concept of a three-domain classification scheme.
RNA: a single stranded macro-molecule that carries genetic information and is
involved in protein synthesis.
rod: a bar shaped or elongated bacterium.
saprotroph: an organism that feeds on dead or decaying organic matter.
seed vascular plant: plant possessing vascular tissue in the form of xylem
andphloem, and which propagates through the dispersal of seeds.
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CyberEd® Multimedia Courseware: Classification of Living Things
seedless vascular plant: plant possessing vascular tissue in the form of xylem
and phloem, which does not produce seeds. Seed vascular plants propagate
through the dispersal of airborn spores.
sexual reproduction: reproduction where new offspring are produced by the
combination of genetic material from two gametes, usually from two different
parents.
six-kingdom classification scheme: an assignment of organisms to six broad
kingdoms: Archaebacteria, Eubacteria, Protista, Fungi, Plantae, or Animalia.
The six kingdom scheme differs from the five kingdom classification scheme in
that kingdom Monera is split into two separate kingdoms, Eubacteria and
Archaebacteria.
species: the narrowest or most specific taxonomic grouping. Also defined as a
genetically similar population of organisms capable of reproducing with other
members of their own species.
spirillum: a spiral or helical shaped bacterium.
synapomorphy: shared derived characteristic. Synapomorphies are
characteristics that arise in a common ancestor and are passed on to all its
descendants.
systematics: the study of living organisms in terms of their diversity and
interrelationships. Taxonomy is a sub-discipline of systematics.
taxonomic key: an organized set of choices that allows a taxonomist to identify
an unknown organism.
taxonomy: the study of classifying and naming organisms.
three-domain classification scheme: classification scheme in which organisms
are assigned to one of three broad domains, Archaea, Eubacteria, or Eukarya,
based on cellular structure, genetics, and nutritional mode.
traditional school of systematics: a school of systematics where classifications
are based on morphological similarities as well as common a ncestry among
organisms.
transcription: a cellular process in which a section of double stranded DNA is
copied in the form of a single strand of RNA.
unicellular: comprised of a single cell.
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CyberEd® Multimedia Courseware: Classification of Living Things
vascular tissue: in plants, specialized groupings of cells in the form of xylem
and phloem that conduct minerals, water, and nutrients throughout the plant.
vertebrate: an animal that possesses a backbone.
vestigial: non-functional structures in an organism that are remnants of
structures that were once func tional in ancestral species of that organism.
xylem: vascular tissue found in some plants that conducts water and minerals
from the roots to the rest of the plant.
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