unit 5- molecular genetics (11&13) Flashcards
(38 cards)
3 main differences between DNA & RNA
DNA- thymine
RNA- uracil
DNA-deoxyribose
RNA- ribose
DNA- double helix
RNA- single twisted strand
4 nitrogenous bases in RNA
- uracil
- adenine
- guanine
- cytosine
What are the complements of nucleic bases in RNA?
- adenine & uracil
- guanine & cytosine
what happens during transcription?
DNA is turned into RNA
- mRNA is created (like DNA replication, but with only one strand & with uracil instead of thymine)
Where does transcription occur?
In the nucleus
translation
changing RNA to amino acids to make proteins
reactants and products of translation
reactant- mRNA
product- amino acids (proteins)
where does translation occur
in ribosomes which are in the cytoplasm
3 parts of a nucleotide in RNA
- ribose sugar
- nitrogenous base
- phosphate
3 types of RNA
- messenger RNA (mRNA)
- ribosomal RNA (rRNA)
- transfer RNA (tRNA)
codon
in RNA, a three-base “word” that codes for one amino acid
what kind of RNA makes up codons
rRNA
3 stop codons
UAA-UAG-UGA
to stop the ribosome from continuing the sequence and messing up the protein being made
start codon
AUG
used to signal where a new amino acid sequence should start
anticodons
a triplet of bases that is complementary to the codon in mRNA
what type of RNA makes up anticodon
tRNA
what is the purpose of the genetic code table?
to “translate” what amino acids that codons code for
mRNA
messenger RNA
- the primary sequence of bases after transcription
- carries the codons out of the nucleus and into the cytoplasm
rRNA
ribosomal RNA
a type of RNA made up to create the ribosome which is needed to change the mRNA into amino acids
tRNA
transfer RNA
the anticodon and directs the amino acid to match up with the codons (anticodon and amino acids are connected together)
mutation
any change in the nucleotide sequence of DNA
3 types of mutuations
- substitution
- deletion
- insertion
substitution (mutation)
switching out one base for another
Ex) aCtgtca -> aTtgtca
deletion (mutation)
taking out a base of the sequence
Ex) aCtgtca -> a_tgtca