Biology Flashcards
(23 cards)
Nucleotide
The basic building block of DNA, consists of a phosphate group, sugar (deoxyribose), and a nitrogen base.
Hydrogen bonds
The type of bond that holds the base pairs together in DNA.
Nitrogen bases (DNA)
The four nitrogen bases found in DNA: Adenine (A), Thymine (T), Cytosine (C), and Guanine (G).
Nitrogen bases (RNA)
The four nitrogen bases found in RNA: Adenine (A), Uracil (U), Cytosine (C), and Guanine (G).
Base-pairing rules (DNA)
The rule that Adenine always pairs with Thymine, and Cytosine always pairs with Guanine in DNA.
Base-pairing rules (RNA)
The rule that Adenine always pairs with Uracil, and Cytosine always pairs with Guanine in RNA.
James Watson and Francis Crick
The scientists who published the double-helix structure of DNA in 1953 and won the Nobel Prize for their work.
Erwin Chargaff
The scientist who discovered the base-pairing rules using percentages of A, T, C, and G in DNA samples from various organisms.
Rosalind Franklin
The scientist who used X-rays to photograph DNA, providing evidence for the double helix structure.
Gene
A segment of DNA that codes for a protein.
Protein
A molecule made up of amino acids that performs various functions in organisms.
Amino Acid
The building blocks of proteins.
Transcription
The first step of protein synthesis, where the mRNA code is synthesized from DNA in the nucleus.
Translation
The second step of protein synthesis, where a protein is synthesized from the mRNA code at the ribosome.
mRNA
Messenger RNA; carries the genetic code from the nucleus to the ribosome to be translated into a protein.
Codon
A sequence of three nucleotides on mRNA that codes for a specific amino acid during translation.
Anticodon
A sequence of three nucleotides on tRNA that is complementary to an mRNA codon during translation.
tRNA
Transfer RNA; brings amino acids to the ribosome to build the protein during translation.
Ribosome
The protein factory of the cell where translation occurs.
Silent (point) Mutation
The change in the base sequence does NOT change the amino acid.
Nonsense (point) Mutation
The change results in a STOP codon resulting in an incomplete protein.
Missense (point) Mutation
The change in the base sequence DOES change the amino acid.
Frameshift Mutation
A nucleotide is inserted or deleted, so the following amino acids are incorrect in the sequence.
