Chapter 10 - Nature, Structure and Organisation of the Genetic Material Flashcards
nucleotides
basic building blocks of nucleic acids
structure of nucleotide
pentose sugar (ribose / deoxyribose)
phosphate group
nitrogenous base
two different types of nucleotides
purines
pyrimidines
purines
AG
double-ringed
pyrimidines
CUT
single-ringed
DNA
2 nucleotides - antiparallel
phosphate-sugar backbone
weak hydrogen bonds
double helix
mtDNA
mitochondrial DNA
double-stranded circular molecule
matrilineal pattern of inheritance
dissociation
double helix strands separated by breaking the hydrogen bonds between the complementary bases
gene
section of DNA that codes for a protein (polypeptide)
template strand
contains the coded information of a particular gene
transcribed during protein synthesis
exons
the part of a gene that contains the coded information for making a protein
introns
‘interruptions’
removed during transcription
flanking regions
regions either side the coding regions
gene sequencing
involves the process of identifying the order of nucleotides along a gene
coded information
DNA template strand
genome
sum total of the genes present in a cell or an organism
mutations
changes that occur in the DNA of an organism
somatic or germline
somatic mutations
Not inherited
Occur only in somatic cells
germline mutations
occur in gametes
heritable
point mutations
change the sequence of nucleotides in DNA for a single gene
substitution mutations
one nucleotide in the DNA is replaced by another
just affects one triplet
addition and deletion mutations
the insertion or deletion of one or more nucleotides into the DNA strand
frameshift mutation
alter ‘reading frame’ from that point onwards
