Chapter 17 Sapling – Flashcards

CUGAUGAGC

Acts on only one strand Catalyzed by RNA polymerase Localized in the nucleus in Eukaryotes

Catalyzed by DNA polymerase RNA primase is required Localized in the nucleus in Eukaryotes

1. RNA polymerase binds to the DNA strand upstream from a gene 2. RNA bases are paired with the DNA bases on the template strand by RNA polymerase 3. RNA polymerase releases the RNA strand, and they both leave the DNA strand

The RNA polymerase binds to the group of transcription factors at the promoter The DNA double helix unwinds, and RNA synthesis begins

The RNA polymerase traverses the DNA template, adding complementary base pairs in the 5' to 3' direction The newly transcribed RNA transcript is proofread for errors

The RNA polymerase detaches from the DNA The RNA polymerase stops adding base pairs when it reaches a certain DNA sequence that signals the end of the gene The RNA transcript is release

The mRNA detaches from the RNA polymerase as the RNA polymerase leaves the DNA strand

It facilitates the binding of RNA polymerase to the promoter to initiate transcription

The region of DNA that is the initial binding site of RNA polymerase during treanscription

mRNA modifications such as additions of a 5' cap and 3' poly-A-tail and removal of introns

A portion of a DNA sequence that is removed from pre-mRNA and not expressed in the protein

an altered guanine nucleotide added to the front of pre-mRNA

Only coding exons are pliced together to make finished mRNA

Carries DNA's protein-building-instructions from the nucleus to the cytoplasm Read as codons, nucleotide triplets that indicate specific amino acids Composed of ribonucleic acid In eukaryotes can exist outside the nucleus

Acts as an enzyme for peptide synthesis Composed of ribonucleic acid In eukaryotes can exist outside the nucleus

Delivers amino acids to the site of protein synthesis Has a anticodon that interacts with a specific codon from another molecular Composed of ribonucleic acid In eukaryotes can exist outside the nucleus

Ribonucleotides that assemble proteins into three dimensional complexes on which polypeptide chains are produced

Occurs in the nucleus Builds strands of mRNA

Occurs in ribosomes Builds a protein Involves tRNA

1. The tRNA molecules that contributed amino acids to the protein chain leave the ribosome 2. The ribosome adds a new amino acid to the growing polypeptide 3. A codon on the mRNA strand binds with the complementary anticodon on a tRNA molecule carrying an amino acid. 4. The mRNA strand binds with the smaller subunit of the ribosome, which moves along the mRNA

The small ribosomal subunit binds with a specific tRNA to the mRNA and scans for a start codon

A tRNA binds a codon and the ribosome adds amino acids from each tRNA to the polypeptide chain.

The ribosome dissociates from the mRNA after the stop codon is recognized by a protein

Translation starts once the 5' end of the mRNA detaches from the DNA Only free-floating ribosomes in the cytoplasm are involved The entire RNA transcript is used without any modifications.

Introns are removed from pre-mRNA before ribosomes can use the mRNA. Mature mRNA has a cap on one end and a poly-A-tail on the other end. Ribosomes may be attached to the ER or free in the cell cytoplasm.