Nucleic acid and the nature of the genetic code
Groups of three bases on DNA.
What is a triplet?
A section of DNA.
What is a gene?
The organelle where protein synthesis takes place.
What is a ribsome?
Linked biochemical reactions catalysed by enzymes.
What is a metabolic pathway?
The physical expression of a genotype.
A monomer composed of sugar (deoxyribose or ribose), phosphate and a nitrogen base.
What is a nucleotide?
Products of gene expression.
What are proteins?
The DNA strand used to make mRNA.
What is the template strand?
A substance that fits into the active site of an enzyme.
What is a substrate?
Remains unaffected despite phenotype changes.
What is genotype?
Ribose
What is the sugar on RNA?
Many amino acid molecules joined together in one chain.
What is a polypeptide?
The DNA strand that contains the base sequence that will be used in protein synthesis.
An interruption in the reaction series preventing the metabolic pathway from progressing to the end.
What is a metabolic disoder?
What is silent mutation?
When several codons code for one amino acid.
What is redundancy?
Globular proteins that catalyse specific reactions.
What is an enzyme?
What is tRNA?
A substrate made in the middle of a metabolic pathway needed to make the final product (protein).
What is an intermediate substrate?
Chemical or physical agent that can cause a permanent change in the DNA sequence.
What is a mutagen?
A number of 3 base combinations specify one amino acid and these codons often differ by only a single base. E.g. Proline is encoded by four different codons.
What is degeneracy?
The chemical bonds holding a protein together become broken and the protein can longer hold its 3D shape.
What is denature (or denaturation)?
Last step of protein synthesis where the mRNA is used to build the a polypeptide chain in the ribosome.
What is translation?
What is a reading frame shift?
What is environmental factor?