Transcript CH. 13 - Weebly

CH. 13
RNA and Protein Synthesis
http://www.youtube.com/watch?v=E
5hdETmm-lU&feature=fvsr
Vocabulary
• RNA: nucleic acid that consists of a long chain
of nucleotides
• Messenger RNA: carry copies of the
instructions
• Ribosomal RNA: make up subunits of RNA
• Transfer RNA: carries amino acids to ribosome
and matches them to the coded mRNA
message
13.1: RNA
SC.912.L.16.5, LA.910.2.2.3
• RNA:
Sugar is Ribose
Single-stranded
Uracil
DNA:
Sugar is Deoxyribose
Double-stranded
Thymine
BOTH:
Adenine
Cytosine
Guanine
Types of nucleic acids
DNA TO RNA
ATTCATGCTAGCATGGGCATTACGTACAGTACTACGT
UAAGUACGAUCGUACCCGUAAUGCAUGUCAUGAUGCA
What’s the RNA strand?
A=U
C=G
*remember uracil NOT thymine!!!!!!!
How does the cell make RNA?
• In transcription, segments of DNA serve as
templates to produce complementary RNA
molecules.
• Complementary:
RNA Polymerase
• Enzyme (remember –ase is an enzyme)
• Separates the DNA strands and helps
assemble nucleotides to DNA template
• Template:
Promoters
• Signals that show the RNA polymerase where
to start and stop making RNA
• Promoter:
Introns vs. Exons
Introns:
Exons:
Cut out and discarded
Remaining pieces
BOTH:
Parts of the DNA template
13.2: Ribosomes and Protein Synthesis
SC.912.L16.9, SC.912.N.1.1, SC.912.L16.5
• What is the genetic code, and how is it read?
• The genetic code is read three “letters” at a
time, so that each “word” is three bases long
and corresponds to a single amino acid.
Codon
• Each 3-letter “word” in mRNA
• This is the CODE that must be decoded in
order for the protein to be made
How to Read Codons
• Open book to page 367 in your text book,
please see Figure 13-6
MEMORIZE
• Start codon: AUG (methionine)
• Stop codon: UGA, UAA, UAG