Biology 1404 Exam Chapter 15-17,21 Review

main goal of this chapter - --Explain the "central dogma" of DNA-protein synthesis -Describe the genetic code and how the nucleotide sequence prescribes the amino acid and the protein sequence -The cellular process of _____ generates messenger RNA (mRNA) - -transcription -messenger RNA (mRNA) - -A type of RNA, synthesized from DNA and attached to ribosomes in the cytoplasm; it specifies the primary structure of a protein. -a mobile molecular copy of one or more genes with an alphabet of A, C, G, and uracil (U) -central dogma of DNA-protein synthesis - -genes specify the sequence of mRNAs, which in turn specify the sequence of amino acids making up all proteins -Protein sequences consist of 20 commonly occurring amino acids; therefore, it can be said that the protein alphabet consists of 20 "letters" . Different amino acids have different chemistries (such as acidic versus basic, or polar and nonpolar) and different structural constraints - -... -Variation in amino acid sequence is responsible for - -the enormous variation in protein structure and function. -Each amino acid is composed of - -an amino group (NH+3NH3+), a carboxyl group (COO-), and a side chain (blue). The side chain may be nonpolar, polar, or charged, as well as large or small. It is the variety of amino acid side chains that gives rise to the incredible variation of protein structure and function. -DNA Encoding RNA - -one nucleotide being added to the mRNA strand for every nucleotide read in the DNA strand