DNA + the genome Flashcards
what is DNA?
the genetic material in the nucleus of a cell
DNA is a ___ and has two strands forming a ___ ___
polymer
double helix
in what structure is DNA contained?
chromosomes
what is a gene?
a small section of DNA on a chromosome
each gene contains the ___ for a sequence of ___ ___, to make a specific ___
instructions
amino acids
protein
what is the genome of an organism?
the entire genetic material of that organism
the whole human genome has been studied. why is this important? (give 4 reasons)
for medicine in the future
to search for genes linked to different types of disease
understanding and treatment of inherited diseases
for tracing human migration patterns from the past
DNA is a polymer made up of 4 ___
nucleotides
what does each nucleotide consist of?
a common sugar
a phosphate group
one of the four different bases attached to the sugar
what are the four bases? (in their pairs)
A + T
C + G
a sequence of 3 bases is the code for what particular acid?
amino
the order of bases gives the ___ for a sequence of ___ ___ which are assembled to produce a particular ___
instructions
amino acid
protein
what may a change in the order of bases result in?
a change in the protein made by the gene (a mutation)
where are proteins made?
on ribosomes
what do carrier molecules bring? to do what?
specific amino acids
to add to the protein chain, in the correct order
what happens when a protein chain is complete?
it folds up to form a unique shape
what does the unique shape enable proteins to do?
their jobs as enzymes, hormones or structures in the body such as collagen
mutations occur ___, most do not alter the ___, or alter it slightly so that its a___ or f___ is not changed
continuously
protein
appearance
function
a few mutations code for an altered protein with a different shape. what would happen to an enzyme if this happened?
an enzyme may no longer fit the substrate binding site or a structural protein may lose its strength
not all parts of DNA code for proteins. what do non-coding parts of DNA do? what will changes in these areas of DNA affect?
switch genes on and off
how genes are expressed
