1. How Proteins are Made

2. How RNA differs from DNA
1st- RNA consists of a single strand of nucleotides instead of the 2 strands found in DNA
RNA
DNA

3. How RNA differs from DNA
2nd- RNA nucleotides contain the five-carbon sugar ribose rather than the sugar deoxyribose found in DNA
One less Oxygen

4. How RNA differs from DNA
3rd- RNA has
A, C, G, and U- Uracil (U bonds with A because no T in RNA)
Example: DNA ATGCATCG
RNA UACGUAGC

5. RNA Nucleotide: Adenine, Guanine
DNA Nucleotide:
Adenine, Guanine
RNA Nucleotide: Uracil, cytosine
DNA Nucleotide:
Thymine, cytosine

6. Transcription and Translation
The instruction for making a protein are transferred from a gene to an RNA molecule in a process called transcription.

7. Transcription and Translation
Cells then use 2 different types of RNA to read the instructions on the RNA molecule and put together the amino acids that make up the protein in a process called translation.

9. Transcription: Making RNA
Step 1: Transcription begins when RNA polymerases bind to the gene’s promoter (a specific sequence of DNA that acts as a “start” signal for transcription.

10. Transcription: Making RNA
Step 2: RNA polymerases then unwind and separate the 2 strands of the double helix, exposing the DNA nucleotides on each strand.

11. Transcription: Making RNA
Step 3: RNA polymerase adds and then links complementary RNA nucleotides as it “reads” the gene.

12. Transcription
Messenger RNA (mRNA) is a form of RNA that carries the instructions for making a protein from a gene and delivers it to the site of translation.

15. Gene Regulation and Structure
In eukaryotes, many genes are interrupted by introns (long segments of nucleotides that have no coding information.

16. Gene Regulation and Structure
Exons are the portions of a gene that are translated (expressed) into proteins.

17. Gene Regulation and Structure
The exons that remain are “stitched” back together by the spliceosomes to form a smaller mRNA molecule that is then translated.

18. Transcription & Codons
The RNA instructions are written as a series of three-nucleotide sequences on the mRNA called codons.
mRNA: AUGGGGCACAAAUAA
Codons: _____ 5

19. mRNA Codon Chart

21. ****EOC QUESTIONS****
A short chain of DNA has the nucleotide sequence ATA CCG. Its complementary mRNA nucleotide sequence is
B. UAU GCC
A. TAT GCC
C. TUT GCC
D. UAU GGC

22. ****EOC QUESTIONS****
What is the maximum number of amino acids that could be coded for by a section of mRNA with the sequence GUCCAGAACUGU?
A. 3
B. 4
C. 6
D. 12

23. ****EOC QUESTIONS****
What is the name of the amino acid coded by AGU?
___________________
Serine

24. Translation: Assembling Proteins
Transfer RNA (tRNA) molecules are single strands of RNA that temporarily carry a specific amino acid on one end.

25. Translation: Assembling Proteins
An anticodon is a three-nucleotide sequence on a tRNA that is complementary to an mRNA codon.

26. ****EOC QUESTIONS****
If a codon reads UGU, what is its anticodon?
A. TCT
B. AGA
D. ACA
C. UGU

27. Translation: Assembling Proteins
Ribosomal RNA (rRNA) molecules are RNA molecules that are part of the structure of ribosomes.

28. Steps of Translation
Step 1: The ribosomal subunits, the mRNA, and the tRNA carrying methionine bind together.
Step 2: The tRNA carrying the amino acid specified by the codon in the A site arrives.

29. Steps of Translation
Step 3: A peptide bond forms between adjacent amino acids.
Step 4: The tRNA in the P site detaches and leaves its amino acid behind.

30. Steps of Translation
Step 5: The tRNA in the A site moves to the P site, the tRNA carrying the amino acid specified by the codon in the A site arrives.
Step 6: A peptide bond is formed. The tRNA in the P site detaches and leaves its amino acid behind.

31. Steps of Translation
Step 7: The process is repeated until a stop codon is reached. The ribosomes complex falls apart. The newly made protein is released.

40. EOC Test Prep 1. Which cellular function does this model represent?
A. Transcription
B. Translation
C. Transformation
D. DNA replication

41. EOC Test Prep 2. Which part of the model represents a codon? F. A G. B
*** Codons are associated with mRNA
H. C
J. D

42. EOC Test Prep 3.What does the part labeled E represent? A. Ribosome
The circles represent amino acids which are what proteins are made up of.
B. Growing protein chain
C. Messenger RNA
D. Transfer RNA

43. Practice mRNA- U G G A C A U U G C U C G G U C A A tRNA- A C C
DNA- A C C T G T A A C G A G C C A G T T
mRNA- U G G
tRNA- A C C
Codon - _____
Amino Acid- Trp
A C A U U G C U C G G U C A A
U G U A A C G A G C C A G U U 6
Thr Leu Leu Gly Gln