Unit 7: Protein Synthesis Flashcards
Activator
A regulatory protein that switches on a gene
Adenine (A)
one of the DNA bases - a purine that consists of a 2-ring structure
Anti-codon
complementary set of 3 nitrogen bases on the tRNA molecule which binds to the
codons on the mRNA strand
Base Pair Rule
complementary base pairs: Adenine (A) always pairs to Thymine (T) and Guanine
(G) always pairs to Cytosine (C)
Central dogma
DNA transcribed to make RNA, which is then used to make proteins.
(DNA -> RNA -> protein)
Chargaff rule
the number of guanine (G) equals the number of cytosine (C); and the number of adenine (A) equals the number of thymine (T)
Chromosomal alteration
mutations that change chromosome structure, and include deletion, duplication, inversion, insertion, and translocation - they often result in the death of the organism
Codon
bases combined in groups of three to form a code - each one coding for one amino acid
Cytosine
one of the DNA bases - a pyrimidine that consists of a 1-ring structure
Deoxyribonucleic acid
DNA - nucleic acid that stores genetic in structions to make proteins -
codes for genes (traits)
DNA polymerase
builder enzyme’ - enzyme that transcribes RNA from a DNA template
DNA replication
process in which DNA is copied during the synthesis phase of the eukaryotic
cell cycle
Double Helix
“spiral staircase’ structure of the DNA molecule
Frameshift mutation
a deletion or insertion of one or more nucleotides that changes the reading frame of the base sequence. Deletions remove nucleotides, insertions add nucleotides
Gene expression
the process by which the information contained in a gene becomes a useful product (a protein); the result of coding information determined by DNA, includes what the organism looks like, and all of the tissue development such as protein building
Genetic code
the sequence of nitrogen bases (A, C, G, U) in a mRNA chain
Germline mutation
changes in DNA that occur in the gametes, can be transmitted to offsprin
and every cell in the offspring will have the mutation
Guanine (G)
one of the DNA bases - a purine that consists of a 2-ring structure
Helicase
enzyme that unwinds a segment of DNA during replication, separating the strands a forming a replication fork.
Hydrogen bonds
complementary base pairs are held together with a hydrogen bond (the DN double helix ‘steps”)
Lagging strand
the strand of replicated DNA that is built in segments called Okazaki fragment
Leading strand
the strand of replicated DNA that is continuously assembled
Ligase
‘gluer’ enzyme that joins the Okazaki fragments on the lagging strand to form a continuous strand of DNA
Messenger RNA (mRNA)
A gene that codes for a protein is transcribed into mRNA. This message is than translated (made) into a protein on the ribosome
Mutagen
physical, chemical, or environmental factor that changes the genetic material
Mutation
A change in the nucleotide sequence of bases in DNA or RNA
Nitrogenous base
molecule that makes up a nucleotide - can be adenine (A), thymine (T),
cytosine (C), or guanine (G)
Nucleotides
molecule made of a sugar (deoxyribose), phosphate group, and a nitrogenous base
(A, T, C, G)
Okazaki fragments
segments of nucleotides that are added together to form the lagging strand in replicated DNA
Point mutation
a change in a single nucleotide in DNA and is usually less serious - can be a
silent mutation; missense mutation, or nonsense mutation (usually serious)
Polypeptide chain
a protein made of a specific sequence of amino acids
Primase
initializer enzyme’ that creates a primer so the DNA polymerase knows where to start
adding bases
Promoter
where RNA polymerase binds to a region of the gene
Protein synthesis
process where proteins are formed by bonding amino acids into long chains
Purines
2-ring molecule that can be part of a nucleotide - adenine (A) and guanine (G) are purines
Pyrimidines
1-ring molecule that can be part of a nucleotide - thymine (T) and cytosine (C) are pyrimidines
Reading frame
dividing the sequence of nucleotides into a set of three bases to form a codon
Regulatory protein
proteins that either turn a gene on’ or ‘off’
Replication fork
Y -shaped structure that forms during the process of DNA replication; the unseparated double stranded DNA represents the base of the Y; the separated single strands are the arms of the Y
Repressor
a regulatory protein that turns a gene off
Ribose
sugarfound in RNA (deoxyribose sugar is in DNA)
Ribosomal RNA (rRNA)
helps form the ribosomes, where proteins are assembled
RNA
ribon ucleic acid - involved in protein synthesis
RNA polymerase
an enzyme that binds to a region of the gene called the promoter
Rosalind Franklin
used X-ray diffraction in 1952 to understand the structure of DNA
Semiconservative
one half of the old DNA strand is always kept in a new strand
Somatic mutation
mutation that occurs in the body cells and may have little effect on the
organism since they are confined to just one cell and it’s daughter cells, these mutations do n pass to offspring
Start codon
the codon AUG (the amino acid methionine) establishes the starting point of reading mRNA
Stop codon (termination codon)
UAG, UGA, and UAA codons do not code for amino acids bu tells mRNA where to stop reading
Thymine
one of the DNA bases - a pyrimidine that consists of a 1-ring structure
Transcription
the process where a cell copies the information in a gene (in the DNA) to
messenger RNA
Transcription factor
proteins that play a central role in regulating transcription to help determin
which genes are active in each cell of the body
Transfer RNA (tRNA)
carries the amino acids to ribosomes where they are joined to form protein
Translation
process where mRNA is decoded and amino acids are bonded together to form a protein
Uracil
nitrogen base found in RNA (instead of thymine T) - pairs with A in RNA
Watson and Crick
discovered the structure of the DNA molecule in 1953, along with others who contributed
