Chapter 25: Transcription, Translation, Regulation, and Mutation Flashcards
What is the structure of RNA?
- made up of nucleotides
- contains ribose sugar
- single-stranded
- contains uracil instead of thymine
What are the bases of RNA?
adenine, cytosine, guanine, uracil
What are the different types of RNA?
rRNA (ribosomal RNA): combines with proteins to form ribosomes
tRNA (transfer RNA): matches mRNA codon to add correct amino acids during protein synthesis
mRNA (messenger RNA): carries codes from DNA to ribosomes
What is the difference between RNA and DNA?
RNA: contains ribose sugar, single-stranded, contains uracil instead of thymine
DNA: contains deoxyribose sugar, double-stranded, contains thymine instead of uracil
transcription
DNA becomes RNA
What are the molecules involved in transcription?
- nucleotides
- DNA
- RNA
- RNA polymerase
What is the difference between introns and exons?
introns: the interviening sequence that are left out
exons: the expressed sequence that are reassembled
Where is transcription located in prokaryotes and eukaryotes?
prokaryotes: operons
eukaryotes: units of protein-coding sequences and adjacent controlling sites
translation
RNA becomes a protein
codons
a group of 3 RNA bases
anticodons
a group of 3 RNA bases that pair with codons
mutation
a change in the genetic material
gene mutation/point mutation
gene mutation: a mutation that produces changes in a single gene
point mutation: a mutation that involves one or a few nucleotides because they occur at a single point in the DNA sequence
What are the different types of gene mutations/point mutations?
- substitutions
- deletions
- insertions
chromosomal mutation
a mutation that produces changes in the number or structure of whole chromosomes
What are the different types of chromosomal mutations?
- deletions
- duplications
- inversions
- translocations
What is the difference between prokaryotic regulation and eukaryotic regulation?
prokaryotic regulation: regulated by operons
eukaryotic regulation: regulated in units of protein-coding sequences and adjacent controlling sites
operon
the collection of controlling sites adjacent to polycistronic protein-coding sequences
What is the regulatory sequence of prokaryotic genes?
regulator genes: codes for a DNA-binding protein that acts as a repressor
promoter: DNA sequence that binds RNA polymerase
operator: a portion of DNA where an active repressor binds
structural genes: codes for enzymes and proteins needed for the operon’s metabolic pathway
What is the regulating sequences of eukaryotic genes?
short-term: genes are quickly turned on or off in response to the environment and demands for the cell
long-term: genes for development and differentiation
hox genes
genes that specify regions of the body plan of an embryo along the head
