Molecular Genetics Flashcards
DNA
Deoxyribonucleic Acid
Double helix shaped like twisted ladder
2 complementary strands running against each other
It is a polymer made of nucleotides
Semi-conservative
One old & one new strand
Telomeres
Special nonsense nucleotide sequences at ends of chromosomes that repeat thousands of times
Ends that protect DNA during cell division
Messenger RNA
Carries messages from DNA in nucleus to cytoplasm during the making of proteins
Codons
Triplet nucleotides of mRNA
Transfer RNA
Carries amino acids to mRNA at ribosome to form polypeptide
Anticodons
Triplet nucleotides of tRNA
Complementary to codons of mRNA
Ribosomal RNA
It is structural, makes up ribosomes along with proteins
Protein Synthesis
Process by which DNA makes proteins
3 main steps: transcription, RNA processing, translation
Transcription
The process by which DNA makes mRNA
Occurs in nucleus
Translation
The process by which the mRNA sequence is converted into an amino acid sequence (proteins)
Occurs in ribosomes
Mutations
Changes in genetic material, it is the raw material for natural selection
Point Mutation
Type of gene mutation
A base-pair substitution where 1 nucleotide converts to another
THE FAT CAT SAW THE DOG -> THE FAT CAT SAW THE HOG
Insertion/deletion
Type of gene mutations
A mutation where 1 nucleotide inserts itself/is lost in existing strand
These mutations result in frame shift, because entire reading frame is altered & unreadable
Chromosome Mutations
Alterations in chromosome number or structure
