Chapter Two Terminology Flashcards
Define ATP
Adenosine Triphosphate, the primary agent that couples exergonic and endergonic reactions.
Define Bilayer
A membrane with two molecular layers.
Define Cell
The smallest unit with the capacity to live and reproduce.
Define Cytoplasm
All parts of the cell that surround the central nuclear or nucleoid region.
Define Cytoskeleton
The interconnected system of protein fibres and tubes that extends throughout the cytoplasm of an eukaryotic cell.
Define Cytosol
Aqueous solution in the cytoplasm that contains ions and various organic molecules.
Define DNA
Deoxyribonucleic acid. The large, double stranded, helical molecule that contains the genetic material for all living organisms.
Define Eukaryote
Organism in which the DNA is enclosed in the nucleus.
Define Flagellum
A long, threadlike, cellular appendage, found in both prokaryotic and eukaryotic cells, but with different structures and modes of locomotion.
Define Gene
A unit containing the code for one of the protein molecules or one of its parts, or for functioning RNA molecules such as rRNA and tRNA.
Define Hydrophobic
Non-polar substances that are excluded by water and other polar molecules.
Define Illumination
The lighting up of a part, cavity, organ, or object for inspection.
Define Magnification
The ration of an object viewed to its real size.
Define Messenger RNA
mRNA. An RNA molecule that serves as a translate for protein synthesis.
Define Microscopy
Technique for producing visible images of objects too small to be seen by the human eye.
Define Nucleic Acid
A complex organic substance present in living cells, especially DNA or RNA, whose molecules consist of many nucleotides linked in a long chain.
Define Nucleoid
The central region of the prokaryotic cell with no boundary membrane separating it from the cytoplasm, when DNA replication and RNA transcription occur.
Define Nucleus
The central region of the eukaryotic cells, separated by membrane from its surrounding cytoplasm, where DNA replication and RNA transcription occur.
Define Organelle
The nucleus and other specialized structures and compartments of eukaryotic cells.
Define Pilus
A hair or hairlike appendage on the surface of a prokaryote.
Define Plasma Membrane
The outer limit of the cytoplasm responsible for the regulation of substances moving into and out cells.
Define Prokaryote
Organism in which the DNA is suspended in the cell interior without separation from other cellular components by a discrete membrane.
Define Resolution
The minimum distance two points in a specimen can be separated and still be seen as two points.
Define RNA
Ribonucleic acid. A polymer assembled from repeating nucleotide monomers in which the five carbon sugar is ribose. Cellular RNA are mRNA (which is translated to produce a polypeptide), tRNA (which brings an amino acid to the ribosome for assembly into a polypeptide during translation), and rRNA (which is a structural component of ribosomes). The genetic material of some viruses is RNA.
