Polypeptide Synthesis Study Notes

The two main strands that make up Deoxyribonucleic acid (DNA) are a sugar (deoxyribose) and phosphate groups backbone, and a nucleotide base (adenine, cytosine, guanine, or thymine).

DNA has a double helix shape, which resembles a twisted ladder.

The four bases known as nucleotides found in DNA are adenine (A), cytosine (C), guanine (G), and thymine (T). Adenine connects with thymine (A+T), and guanine connects with cytosine (G+C).

<p>Chargaff's first rule states that the amount of one purine base always equals the amount of the pyrimidine base. The second rule shows that the composition of DNA varies between species. These rules provide evidence that DNA is the genetic material and support the base pairing rule.</p> Signup and view all the answers

<p>DNA provides the instructions for making proteins, which are essential for building and maintaining human tissues and organs.</p> Signup and view all the answers

<p>DNA is found in the nucleus, while RNA is found in the cytoplasm.</p> Signup and view all the answers

<p>Transcription is the process where DNA is copied into a molecule of mRNA.</p> Signup and view all the answers

<p>Transcription occurs in the nucleus.</p> Signup and view all the answers

<p>mRNA carries the genetic information from DNA to the ribosomes, where protein synthesis takes place.</p> Signup and view all the answers

<p>The stages of transcription are initiation, elongation, and termination.</p> Signup and view all the answers

<p>The promoter is a DNA sequence that signals to RNA polymerase where to bind and begin transcription.</p> Signup and view all the answers

<p>Pre-mRNA is a transcript of a protein-coding gene in eukaryotic cells that needs to be processed before translation.</p> Signup and view all the answers

<p>The two ends that are modified in pre-mRNA are the 5' cap and the 3' poly-A tail.</p> Signup and view all the answers

<p>Splicing removes introns, which are non-coding sequences, from pre-mRNA, and joins the remaining exons together to form mature mRNA.</p> Signup and view all the answers

<p>RNA polymerase unwinds DNA and adds complementary RNA nucleotides to the growing mRNA strand.</p> Signup and view all the answers

<p>The RNA transcript is almost identical to the coding strand of DNA, except that thymine (T) is replaced by uracil (U).</p> Signup and view all the answers

<p>The terminator is a DNA sequence that signals to RNA polymerase to stop transcription.</p> Signup and view all the answers

<p>The three steps of translation are initiation, elongation, and termination.</p> Signup and view all the answers

<p>The start codon (AUG) signals to the ribosome where to begin translation.</p> Signup and view all the answers

<p>tRNA carries specific amino acids to the ribosome and pairs with corresponding codons in mRNA.</p> Signup and view all the answers

<p>The three tRNA binding sites on the ribosome are the A site (aminoacyl site), P site (peptidyl site), and E site (exit site).</p> Signup and view all the answers

<p>Release factors recognize stop codons, and they cause the ribosome to release the newly synthesized polypeptide chain.</p> Signup and view all the answers

<p>tRNA has a folded structure resembling a three-leaf clover.</p> Signup and view all the answers

<p>The anticodon on tRNA recognizes and binds to a specific codon on mRNA.</p> Signup and view all the answers

<p>tRNA acts as a decoder for the language of mRNA, matching a specific codon to its corresponding amino acid and bringing it to the ribosome for incorporation into the growing polypeptide chain.</p> Signup and view all the answers

<p>A codon table lists all possible mRNA codons and their corresponding amino acids. To decode an mRNA sequence, find the first three bases of a codon, locate it on the codon table and then identify the amino acid it represents, then repeat this for each codon in the sequence.</p> Signup and view all the answers

<p>A codon table typically features the first, second, and third bases of a codon displayed across three axes. This table helps decipher each codon and its corresponding amino acid.</p> Signup and view all the answers

<p>Amino acids are essential for building proteins, which are vital for all human functions. They are also needed for neurotransmitters, hormones, and energy production.</p> Signup and view all the answers

<p>Proteins perform diverse roles in the body, including repair and building tissues, transporting and storing nutrients, acting as enzymes to catalyze reactions, and helping to fight pathogens.</p> Signup and view all the answers

<p>Polypeptides regulate the functions of various systems, organs, tissues, and cells in the body, and they are vital for growth.</p> Signup and view all the answers

<p>Proteins are made up of amino acids linked by peptide bonds, while polypeptides are made up of sugars.</p> Signup and view all the answers

<p>My model provides a simplified view of complex processes, making it easier to understand. It also accurately reflects the base pairing rules and provides a visual representation of polypeptide synthesis.</p> Signup and view all the answers

<p>The model's simplification can be inaccurate, such as the representation of DNA and mRNA lengths. It also does not fully represent the complexity of polypeptide synthesis and is limited to two dimensions.</p> Signup and view all the answers

<p>The model offers a simplified perspective for understanding the complex processes of transcription and translation. However, its simplification can lead to inaccuracies. The length representation of DNA and mRNA, alongside the model's two dimensionality, are limitations. I would improve the model by adding more detail, depicting three dimensions, and ensuring accurate length presentations of DNA, mRNA, and polypeptide chains.</p> Signup and view all the answers