1. Chapter 11.2

2.  Relate the concept of the gene to the sequence of nucleotides in DNA  Sequence the steps involved in protein synthesis ◦ DNA  mRNA = “transcription” ◦ mRNA  protein = “translation”

3.  The sequences of nucleotides in DNA contain information that code for production of proteins  These proteins fold into 3-d shapes that have different functions in key processes ◦ Usually ENZYMES  Used in active transport, ATP-ADP cycle, etc.  Proteins are polymers of amino acids ◦ A.P.E.

4.  Single stranded  Sugar is “ribose”  RNA has “U” rather than “T” in its code ◦ RNA’s nitrogen bases are: AA UU CC GG  RNA molecules are “workers” of protein synthesis

5.  There are 3 types of RNA molecules ◦ mRNA (messenger RNA) ◦ rRNA (ribosomal RNA) ◦ tRNA (transfer RNA)

6.  Transcription is moving from DNA to a single mRNA strand ◦ Occurs in the nucleus of a cell ◦ mRNA carries genetic information through nuclear envelope to the ribosomes in the cytoplasm for protein synthesis

8.  Introns: non-coding portions of DNA  Exons: coding portions of DNA  Both are copied from DNA to mRNA, but one is removed before piecing together the protein from mRNA

9.  Based off sequence of nucleotides  Proteins contain chains of amino acids  There are 20 common amino acids  Group of 3 nitrogen bases (AAA) is called a codon  64 different possible codons ◦ Table 11.1 pg. 92  More than 1 codon = same amino acid  1 codon can only be 1 amino acid ◦ With exception of AUG = start, methionine codon

11.  The genetic code is UNIVERSAL ◦ Because all organisms use the same genetic code, thus meaning we must all have a common origin

12.  Moving from mRNA to protein  Translation: process of converting information in a sequence of nitrogen bases in mRNA into a sequence of amino acids (protein)  Takes place in the cytoplasm wherever ribosomes are  Amino acids are held together by PEPTIDE BONDS

13.  A. The Role of Transfer RNA (tRNA) ◦ Attaches to only 1 type of amino acid ◦ Has the “ANTICODON” for the mRNA codon  B. Translating the mRNA code ◦ Start and stop codons ◦ Ribosomes (rRNA) slide down the mRNA molecule and signal to bring in the correct tRNA molecule with the correct amino acid for forming a protein ◦ tRNA releases protein and goes back to pick up another free floating amino acid

14.  B. Translating the mRNA code ◦ Ribosome continues to slide down mRNA to next codon sequence, etc, etc etc ◦ Proteins fold into 3-d shapes to become enzymes and cell structures

18.  http://learn.genetics.utah.edu/content/begin /dna/transcribe/