DNA, genes and chromosomes Flashcards
What does a gene sequence of DNA bases code?
It codes for a polypeptide or functional RNA
What does the sequence of amino acids in a polypeptide form ?
The primary structure of protein
Different amino and order of amino acids?
Different polypeptides have different numbers and order of amino acids.
Its the order of bases in a gene that determines the order of amino acids
What is three bases in a gene are called ?
Triplet
How to make a polypeptide?
DNA is first copied into mRNA,
Whats another form of a gene?
An allele
What do alleles code for?
They code for slightly different versions of the same polypeptide as each allele is different.
They code for characteristics
What is a homologous pair?
Pairs of matching chromosomes, both chromosomes are the same size and have the same gene, could have different alleles
What are introns?
Gene section that doesn’t code for polypeptides contain introns.
Introns are removed during protein synthesis- so they don’t effect the amino acid order
What are exons?
All the bits of the gene that do code for amino acids.
What are non-coding repeats?
They are regions in eukaryotic DNA which contains multiple repeats outside of genes, these are sections which repeat over and over.
These areas don’t code for amino acids either.
What does locus mean in relation to DNA?
Locus is the location of a gene on a chromosome.
What are introns and ex trons in relation to DNA?
Introns - non coding
Ex trons- coding
What are the components of DNA?
A sugar (deoxyribose) (pentossugar)
A phosphate group
Nitrogenous
