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chapter 24
notes
deducted the actual structure of DNA | James Watson and Francis Crick |
the part of the DNA molecule that controls a particular trait | gene |
protein spools in the DNA | histones |
a structure in all living cells that consists of a single molecule of DNA bonded to various proteins and that carries the genes determining heredity | chromosomes |
groups of eight histones clustered together | muleosome |
the material of which the chromosomes of organisms other than bacterial are composed. It consists of protein, RNA, and DNA | chromatin |
a nucleic acid present in all living cells and many viruses, consisting of a long, usually single-stranded chain of alternating phosphate and ribose units, with one of the bases adenine, guanine, cytosine, or uracil bonded to each ribose molecule | ribonucleic acid |
the coiled structure of a double-stranded DNA molecule in which strands linked by hydrogen bonds form a spiral configuration | double helix |
a purine base, that is a fundamental constituent of DNA and RNA, in which it forms base pairs with cytosine | guanine |
is an important part of DNA and RNA, where it is one of the nitrogenous bases coding the genetic information these molecules carry | cytosine |
a purine base that is a component of DNA and RNA, forming a base pair with thymine in DNA and with uracil in RNA | adenine |
a pyrimidine base, that is one of the principal components of DNA, in which it is paired with adenine | thymine |
DNA and RNA are in the form of strands of molecules, a strand of DNA is composed of four nitrogenous bases known as adenine, guanine, thymine, and cytosin, RNA is different from DNA because it does not have thymine, instead, it has a base known as | uracil |
the process by which genetic material, a single-celled organism, or a virus reproduces or makes a copy of itself | replication |
the movement of a chemical substance through a gradient of concentration or electrical potential in the direction opposite to normal diffusion, requiring the expenditure of energy | transportation |
is the process in which cellular ribosomes create proteins | translation |
is an enzyme used to generate complementary DNA from an RNA template | reverse transcription |
transcribed from the DNA of a gene, and from which a protein is translated by the action of ribosomes | messenger RNA |
small RNA molecules that carry amino acids to the ribosome for polymerization into a polypeptide | transfer RNA |
a molecular component of a ribosome, the cell's essential protein factory | ribosomal RNA |
is a sequence of three DNA or RNA nucleotides that corresponds with a specific amino acid or stop signal during protein synthesis | codon |
is highly similar among all organisms and can be expressed in a simple table with 64 entries, the code defines how sequences of nucleotide triplets, called codons, specify which amino acid will be added next during protein synthesis | genetic code |
is a nucleotide triplet within messenger RNA that signals a termination of translation | stop codons |
is the first codon of a messenger RNA transcript translated by a ribosome | start codons |
is the process in which cellular ribosomes create proteins | translation |
is the process of producing similar populations of genetically identical individuals that occurs in nature when organisms such as bacteria, insects or plants reproduce asexually | cloning |
a segment of a gene situated between exons that does not function in coding for protein synthesis | introns |
is any part of a gene that will become a part of the final mature RNA produced by that gene after introns have been removed by RNA splicing | exons |
occurs when a DNA gene is damaged or changed in such a way as to alter the genetic message carried by that gene | mutations |