(Alberts) Complete Review
archaea ✔- One of the two divisions of prokaryote, often found in
hostile environments such as hot springs or concentrated brine.
bacteria ✔- Commonly used name for any prokaryotic organism,
but more precisely refers to the eubacteria, the "true bacteria," one of
the three major domains of life. Most are single-celled organisms. Some
species of bacteria cause disease.
cell ✔- The basic unit from which living organisms are made,
consisting of an aqueous solution of organic molecules enclosed by a
membrane. All cells arise from existing cells, usually by a process of
division.
chloroplast ✔- Specialized organelle in algae and plants that
contains chlorophyll and in which photosynthesis takes place.
chromosome ✔- Long threadlike structure composed of DNA and
associated proteins that carries the genetic information of an organism.
Especially visible when plant and animal cells undergo mitosis and
meiosis.
cytoplasm ✔- Contents of a cell that are contained within its
plasma membrane but, in the case of eukaryotic cells, outside the
nucleus.
cytoskeleton ✔- System of protein filaments in the cytoplasm of a
eukaryotic cell that gives the cell shape and the capacity for directed
movement. Its most abundant components are actin filaments,
,microtubules, and intermediate filaments.
cytosol ✔- Contents of the main compartment of the cytoplasm,
excluding membrane-enclosed organelles such as endoplasmic
reticulum and mitochondria. The cell fraction remaining after
membranes, cytoskeletal components, and other organelles have been
removed.
DNA
(deoxyribonucleic acid) ✔- Double-stranded polynucleotide formed
when two separate chains of covalently linked deoxyribonucleotide
units. It serves as the cell's store of genetic information that is
transmitted from generation to generation.
eucaryote ✔- Living organism composed of one or more cells with a
distinct nucleus and cytoplasm. Includes all forms of life except archaea
and bacteria (the prokaryotes) and viruses.
evolution ✔- The gradual change in living organisms taking place
over generations that result in new species being formed.
genome ✔- The total genetic information carried by a cell or an
organism (or the DNA molecules that carry this information).
homologous ✔- Describes organs or molecules that are similar
because of their common evolutionary origin. Specifically it describes
similarities between protein sequences or nucleic acid sequences.
micrometer
(μm) ✔- Unit of measurement often applied to cells and organelles.
Equal to 10^-6 meter.
microscope ✔- Instrument for viewing extremely small objects.
, Light microscope utilizes a focused beam of visible light and is used to
examine cells and organelles. An electron microscope utilizes a beam of
electrons and can be used to examine objects as small as individual
molecules.
mitochondrion ✔- Membrane-enclosed organelle, about the size of
a bacterium, that carries out oxidative phosphorylation and produces
most of the ATP in eukaryotic cells.
model organism ✔- An organism selected for intensive study as a
representative of a large group of species. Examples are the mouse
(representing mammals), the yeast (representing a unicellular
eucaryote), and Escherichia coli (representing bacteria).
nanometer
(nm) ✔- Unit of length commonly used to measure molecules and
cell organelles. Equal to 10^-9 meters.
nucleus ✔- The major organelle of a eukaryotic cell, which contains
DNA organized into chromosomes. Also, when referring to an atom, the
central mass built from neutrons and protons.
organelle ✔- A discrete structure or subcompartment of a
eukaryotic cell (especially one that is visible in the light microscope)
that is specialized to carry out a particular function. Examples include
mitochondria and the Golgi apparatus.
procaryote ✔- Major category of living cells distinguished by the
absence of a nucleus. Procaryotes comprise the archaea and the
eubacteria (commonly called bacteria), two of the three domains of life.
protein ✔- The major macromolecular constituent of cells. Each
protein is composed of one or more linear chains of amino acids linked
together by peptide bonds in a specific sequence. The amino acid chain
is folded into a 3D shape that is unique to the given protein and
determines its function.