1. Take out your HW: Transcription wkst
Homework due tomorrow:
Protein Synthesis wkst
Somewhere on a sheet of scratch paper or in your notes, TRANSCRIBE the following DNA sequence into mRNA:
TAC AGT CCA GCG ATA ATT
AUG
UCA
GGU
CGC
UAU
UAA

2. TRANSCRIPTION & TRANSLATION: From DNA to Protein
Chapter 11, Section 2
Think back to the information contained in your homework assignment:
What is produced when the process of transcription is complete?
What are 2 differences that were listed/shown between DNA and RNA?

3. Genes & Proteins What is the function of a gene?
codes for traits, inherited from parents
Genes code for specific proteins
Proteins make up muscles, hair, tissues, enzymes, & pigments
Protein Synthesis = reading the DNA, forming RNA, using RNA to make the protein (DNA  RNA  Protein)
Occurs through the processes of transcription and translation

5. RNA RNA is a nucleic acid (like DNA) Differs in structure from DNA:
Number of Strands 2 1
Nucleotide Sugar
Deoxyribose
Ribose
Nitrogenous Base Pairs
Thymine(T), Adenine(A), Guanine (G), Cytosine (C)
Uracil (U), Adenine(A),
Guanine (G),
Cytosine (C)

7. Focusing on RNA
There are 3 different types of RNA that you will need to know:
mRNA
rRNA
tRNA

8. Types of RNA 1. Messenger RNA (mRNA)
Carries genetic “message” from DNA to the ribosomes in the cytosol
“Read” by ribosomes to make proteins
Contain codons

9. 2. Ribosomal RNA (rRNA)
Part of the structure of ribosomes
Ribosome = protein and rRNA

10. 3. Transfer RNA
Transfers amino acids to the ribosome to make protein

11. Transcription: Getting the message out of the nucleus
Transcription = enzymes make RNA by copying a portion of DNA in the nucleus
If a DNA sequence is AATCCGGA, what is the complimentary RNA sequence?
UUAGGCCU
The mRNA that gets sequenced is sent out of the nucleus to help make protein

12. Genetic Code
Sequence of Nitrogenous Bases codes for a specific Amino Acid that is connected to other amino acids to make a Protein
Codon = the nitrogenous bases of 3 adjacent nucleotides in mRNA that code for
Start Signal (starts the protein making process)
1 of 20 different amino acids (parts of a protein)
Stop Signal (stops the protein making process)
Codons are like 3-letter words
Words contain meaning to us: CAT =
Codons contain meaning in the form of an amino acid
CAU = Histidine

13. An amino acid can be coded for by more than one codon
20 amino acids combine in different combinations to make various proteins

14. Translation: Going from the language of bases (AUGC) to proteins
Translation = using the mRNA to make protein, reading the codons
Takes place at the ribosomes
The mRNA is “read” in between the 2 sub-units of the ribosome
tRNA carries the amino acid coded for by the mRNA codons and has an anticodon that pairs up with the mRNA codon
Codon (mRNA) and anticodon (tRNA) follow RNA base-pairing rules
Amino acids form peptide bonds between each other to create a long chain of amino acids

15. Transcription

16. Amino acids to protein
Amino acid chains start to fold creating 3-dimensional structures
Several of these 3-D structures combine to form a functional protein
These proteins then carry out cellular functions