Gene expression Flashcards
Allele
An alternate form of a gene (e.g blue eyes)
Chromosome
A long molecule of DNA
Gene
A length of DNA that codes for a particular trait (e.g eye colour)
DNA
It’s a double helix that contains the genetic code. It’s made up of sugar, phosphate and nucleotide.
Phentoype
Is the physical expression of a trait
Gentoype
The genetic material of a trait
DNA triplet
A series of 3 bases in DNA, each triplet codes for a specific amino acid.
Ribosome
An organelle where translation (the making of proteins) takes place
mRNA
A single stranded copy of a gene, that carries the genetic code from the nucleus to a ribosome. `
Transcription
The process of making mRNA from DNA.
Translation
The process of making a protien from mRNA
Template strand
A single strand of DNA where complimentary nucleotides are added to make mRNA
tRNA
A type of RNA with an anticodon on one end and a specific amino acid attached to the other end.
Mutation
A permanent change in the base sequence of DNA, that may result in new alleles.
Enzyme
A type of protien which functions as biological catalyst to speed ip reactions inside living things.
Substrate
The reactant that is catlysed bya specific enzyme
Base substitution mutation
Is a form of mutation where a single nucleotide base is replaced or substituted with another.
Same-sense
The substituted base does not cause a change in the amino acid sequence
Missense
Causes a change in the amino acid sequence, but does not cause a change in the shape or function of the protein.
Nonsense
Substituted base results in the production of a stop codon, has a severe impact on the protein formed.
Single base insertion
A form of DNA mutation where one base is added into the DNA chain, changing the genetic code dramatically.
Single base deletion
A form of DNA mutation where one base is removed from the DNA chain, and lost forever.
Reading frame-shift
A genetic mutation caused by a deletion or insertion of a base in a DNA sequence that shifts the way the sequence is read (in triplets).
Examples of mutagens
Chemicals
Ultraviolet Light
Radiation
Silent (or Neutral) mutation
Which has no observable effects on an organism.
Beneficial mutation
The individual has a survival advantage that the other member of its species doesn’t.
Harmful mutation
Detrimental to an organism and affects its survival.
Somatic cells
Examples
May affect the individual in its lifetime though not be passed on to the next generation.
Skin cells and liver cells
Gametic cells
Examples
Is pass on to the next generation and may affect the survival of the offspring.
Sperm cells and egg cells
Effect of the environment
Gentotype + Environment = Phenotype
