Biology I- Chapter 12 questions

What does gene expression refer to?

the process by which information from a gene is used in the synthesis of a functional gene product

What is the central dogma of gene expression?

Transcription and Translation

What are the structures of the RNA nucleotide and RNA molecule?

*Know the three parts of the nucleotide and be able to identify them.

*Be able to compare and contrast to the DNA nucleotides and molecule.

What are the three main classes of RNA and their functions and roles in gene expression?

Messenger (mRNA)→the product of transcription from a protein-coding gene that “carries” the protein-building instruction.

*Acts as the bridge between DNA and protein synthesis.

Transfer (tRNA)→delivers amino acids to ribosomes for the process of assembling amino acids into proteins.

Ribosomal (rRNA)→the major component of ribosomes involved in the process of assembling amino acids into proteins.

*rRNA and tRNA are non-coding RNA molecules; they function in the form of RNA and are not translated into proteins.

Know the process of transcription.

*Where does it occur within the cell?

*Compare and contrast to the mechanism of DNA replication.

*What are the three stages?

the synthesis of RNA from a DNA template where the code in the DNA is converted into a RNA code.

occurs in the nucleus

*Only one strand of the DNA is as the template used.

*Uracil (U) is put in the place of Thymine (T).

*The product is a single strand of RNA.

Initiation, Elongation, and Termination

What is the genetic code?

*Understand what a codon is.

*Know how to use the mRNA codon chart.

specifies the relationship between the nucleotides of mRNA and the amino acids used to build a protein.

DNA → mRNA → Protein

read in groups of three nucleotides, called codons.

Know the process of translation.

*Where does it occur within the cell?

*What are the three stages?

the process of making a protein from mRNA.

occurs in the ribosome

Initiation: brings together the mRNA, a tRNA with the first amino acid, and the ribosome at the start codon.

Elongation: the ribosome moves (?) along the mRNA,covalently attaching each amino acid to the previous

Termination: occurs when one of the three stop codons is reached resulting in the release of the protein and translation complex.

What is the relationship between ribosomes, protein synthesis, and the endomembrane system?

Those proteins made at the rER will make their way through the endomembrane system

Those proteins made at ribosomes in the cytosol will either function within the cytosol or be transported to various organelles.