Science Flashcards
What is a nucleotide sequence?
Order of A, T, C, and G’s that give a nucleic acid its coding/meaning.
What does complementary mean in the context of nucleotides?
Nucleotides pair up using a complementary pattern.
What are the complementary pairs in DNA?
A-T, C-G.
What are the complementary pairs in DNA-RNA?
A-U; T-A; C-G; G-C.
What is the DNA double-helix?
Two twisting nucleotide strands discovered by Watson and Crick.
What is a gene?
A DNA sequence that is expressed to lead to a particular trait.
What is a nucleotide?
DNA or RNA building block: sugar, phosphate, nitrogenous base.
What sugar is found in DNA?
Deoxyribose sugar.
What sugar is found in RNA?
Ribose sugar.
What is a genotype?
Genetic makeup composed of genes/DNA sequences.
What is a phenotype?
Physical characteristics caused by the genotype (or environmental factors).
What is DNA replication?
Copied according to semi-conservative model.
What are the steps of DNA replication?
- Unwinding/separating parent DNA double-helix by Helicase enzyme. 2. Using each parent strand as template. 3. DNA polymerase enzyme adds complementary nucleotides to each strand to create daughter strands. 4. Resulting DNA molecules: composed of two complementary strands; one original and one daughter strand; have identical base-pair sequences to each other and to the original DNA molecule.
What is the Central Dogma of molecular biology?
DNA codes for RNA, which codes for proteins (amino acid sequences).
What is transcription?
Process of building complementary RNA strand from DNA template.
What is RNA polymerase?
Enzyme that builds an RNA strand complementary to a DNA gene sequence.
What is mRNA?
Messenger RNA. ‘Blueprint’ copy of DNA instructions to build a protein.
What is RNA splicing?
The process of removing non-coding introns from mRNA to leave exon coding sequence.
What is translation?
Process of building an amino-acid chain into a polypeptide.
What is a ribosome?
Structure that builds the polypeptide out of amino acids by reading the mRNA codons.
What are amino acids?
Building blocks of the polypeptide.
What is a polypeptide?
String of amino acids as dictated by the codons in the genetic code.
What is tRNA?
Molecules that bring individual amino acids to the ribosome to help build the polypeptide.
What is a codon?
3 nucleotide mRNA sequence that codes for a single amino acid.
