Protein Synthesis and Mutation
Proton Synthesis
Transcription, which happens in the nucleus, uses the DNA sequence to make an RNA molecule
The RNA then leaves the nucleus and goes to the cytoplasm where translation occurs on a ribosome and produces a protein
The central dogma of molecular biology deals with the detailed residue-by-residue transfer of sequential information
click to edit
With three biopolymers (DNA, RNA, and protein), there could be as many as nine potential types of transfers. The central dogma classes these into three groups of three
three general transfers,
three special transfers,
three unknown transfers.
Reverse transcription is the transfer of information from RNA to DNA
A
biopolymer is a polymer produced by living organisms composed of linked monomers.
The regions of mRNA that code for proteins are called exons
Splicing removes introns from mRNA.
genetic code consists of the sequence of nitrogen bases—A, C, G, U—in an mRNA chain
the start codon that begins translation
The reading frame is the way the letters are divided into codons
The mRNA molecule is read, codon by codon, until a stop codon is reached
Translation always starts with a(n) AUG codon
Genetic information is present in DNA
A codon is a sequence of three nucleotides within mRNA that encodes for a specific amino acid or termination sequence
The genetic code is redundant because a single amino acid may be coded for by more than one codon
The
genetic code is the universal code of three-base codons which encodes the genetic instructions for the amino acid sequence of proteins.
Translation
The mRNA moves from the nucleus to the cytoplasm to interact with a ribosome, which serves as the site of translation
Translation proceeds in three phases: initiation, elongation and termination
Transfer RNAs or tRNAs bring or tansfer the proper amino acid to the ribosome based on the genetic code
The anticodon at the bottom of the tRNA molecule binds to the codon on the mRNA
The covalent attachment of an amino acid to the tRNA is catalyzed by enzymes called aminoacyl-tRNA syntheses through a process called aminoacylation
The tRNAs with attached amino acids are delivered to the ribosome by proteins called elongation factors (EF-Tu in bacteria, eEF-1 in eukaryotes), which aid in decoding the mRNA codon sequence
The anticodons found on the tRNA complement the codons on the mRNA
Anticodons are found on tRNA
During translation, the mRNA is read in groups of three bases
Which of the following are types of chromosomal alterations? duplications
insertions
Alu sequences are repetitive elements that form a significant part of the human genome
click to edit
Evolution could not take place without the genetic variation that results from
beneficial mutations.
A silent mutation codes for the same amino acid
The
germline mutations change the DNA sequence within a sperm or egg, therefore can be passed on to descendants
A frame shift mutation changes the reading frame of the mRNA
Haploinsufficiency results in when a
reduced dosage of a normal gene product does not produce a normal phenotype
Gain -of-function mutations result in the gene product or protein having a new and abnormal function
If a mother has a mutation in her gametes,
her child will have the mutation in all of his/her cells