Table of Contents
What is a sequence of proteins called?
Protein primary structure is the linear sequence of amino acids in a peptide or protein.
When mRNA is translated into a protein the ribosome always begins reading at?
At the start of the initiation phase of translation, the ribosome attaches to the mRNA strand and finds the beginning of the genetic message, called the start codon (Figure 4). This codon is almost always AUG, which corresponds to the amino acid methionine.
How are the following terms related mRNA amino acid and codon?
Each group of three bases in mRNA constitutes a codon, and each codon specifies a particular amino acid (hence, it is a triplet code). The mRNA sequence is thus used as a template to assemble—in order—the chain of amino acids that form a protein.
What contributes methionine to the amino acid chain?
– In response to the base sequence AUG contributes methionine to the amino acid chain.
Do all proteins have a quaternary structure?
In contrast to the first three levels of protein structure, not all proteins will have a quaternary structure since some proteins function as single units. Protein quaternary structure can also refer to biomolecular complexes of proteins with nucleic acids and other cofactors.
What organelle makes proteins by reading the mRNA?
ribosome
During protein synthesis, an organelle called a ribosome moves along the mRNA, reads its base sequence, and uses the genetic code to translate each three-base triplet, or codon, into its corresponding amino acid.
What happens when the ribosome reaches a stop codon on mRNA?
Lastly, termination occurs when the ribosome reaches a stop codon (UAA, UAG, and UGA). Since there are no tRNA molecules that can recognize these codons, the ribosome recognizes that translation is complete. The new protein is then released, and the translation complex comes apart.
Where are proteins made?
Ribosomes
Ribosomes are the sites where proteins are synthesised. The transcription process where the code of the DNA is copied occurs in nucleus but the main process of translating that code to form other protein occurs in ribosomes.
How are proteins built using the information provided by a molecule?
How are proteins built using the information provided by a molecule of RNA? RNA determines the sequence of amino acids in proteins and polypeptides by a two-step process: transcription of DNA produces mRNA in the nucleus, then translation of the mRNA to tRNA takes place in the ribosome in the cytoplasm.