1. RNA and Protein Synthesis
BIOLOGY
Chapter 10-2 and 10-3 (pgs )

2. BIG IDEAS
The information needed to make proteins in located in the nucleus in the form of DNA
The enzymes and amino acid building blocks of proteins are located outside the nucleus in the cytosol
RNA (ribonucleic acid) is responsible for getting the genetic information to the site of protein synthesis (ribosomes)

3. Review of DNA & Proteins:
Organic molecule (nucleic acid) that is composed of repeating subunits - nucleotides
Stores and transmits the genetic information in the form of ‘genes’
Controls the production of protein
PROTEIN-
Organic molecule made up of repeating subunits – amino acids
Important in all cell functions: repair, energy, hormones, enzymes, transportation and storage and immunity.

4. FYI…
Each ‘gene’, or section of DNA, is made up of a sequence of nucleotides arranged in a specific order according to our genetic ancestry.
The order of these base units makes up the genetic information or “code” for the SYNTHESIS of PROTEINS in the body.
A strand of DNA may be millions, or billions, of base-pairs long. Different segments of the DNA molecule code for different characteristics in the body. A Gene is a relatively small segment of DNA that codes for the synthesis of a specific protein. This protein then will play a structural or functional role in the body. A chromosome is a larger collection of DNA that contains many genes and the support proteins needed to control these genes.

5. Protein Synthesis ? QUESTION ?
In all cells, except for bacteria, DNA is stored in the nucleus and protein synthesis takes place in the ribosome in the cytoplasm..
? QUESTION ?
So, how do cells use the genetic information, or ‘code’ stored in DNA to make millions of different proteins the body needs?
The genetic code controls protein production. Hundreds of thousands of proteins exist. No two people have the same proteins, except for identical twins.
They are used to build materials, transport substances in and out of the cell, send signals, provide defense, control chemical and metabolic activities.
These small organelles are scattered throughout the cytoplasm of the cell.
And with over 100,000 proteins to manufacture…
Each strand of DNA contains millions or even billions (in the case of human DNA) of nucleotide bases. These bases are arranged in a specific order according to our genetic ancestry. The order of these base units makes up the code for specific characteristics in the body, such as eye color or nose-hair length. Just as we use 26 letters in various sequences to code for the words you are now reading, our body's DNA uses 4 letters (the 4 nucleotide bases) to code for millions of different characteristics.

6. This is how we do it….
The DNA (deoxyribonucleic acid) that contains the genetic code to make all of your proteins is trapped in the nucleus of the cell
The ribosomes, enzymes, and amino acid building blocks of protein are out in the cytoplasm
RNA (ribonucleic acid) is responsible for getting the ‘code’ from the nucleus to the cytoplasm
RNA Copies DNA and then moves outside the nucleus to synthesize proteins in the ribosome

7. RNA – Ribonucleic Acid
Like DNA , RNA is a nucleic acid made up of repeating nucleotides
Differs in structure:
1. Sugar (ribose)
2. *Phosphate (same in both)
3. 1 of the four
Nitrogenous Bases
(A, G, C, T in DNA U in RNA)
4.Single strand – RNA
Double strand - DNA

8. FYI - RNA RNA differs from DNA in several ways.
An RNA molecule has only one side of the ladder shape.
RNA has the bases A, G, and C. However, it has a base U or Uracil, instead of base T or thyamine.
So when forming base pairs, base A pairs with base U.
Try an example:

9. Comparison of DNA and RNA:
Nucleotide Components
Function
Form/Structure
Sugar
Nitrogen Base
DNA
Deoxyribose
Adenine, Guanine, Cytosine,
Thymine
Store and transmit genetic info. that tells cells which proteins to make and when.
2 strands of nucleotides.
Double Helix
RNA
Ribose
Adenine, Guanine, Cytosine, Uracil
Move genetic info. from DNA to ribosomes; assemble polypeptide chains (proteins)
Single strand of nucleotides.
Single Helix

10. 3 Types of RNA:
RNA: ribonucleic acid. Use information from DNA to make proteins.
1. mRNA – messenger RNA
2. tRNA – Transfer RNA
3. rRNA – Ribosomal RNA

11. Messenger RNA (mRNA)
Single, uncoiled chain of RNA that transcribes DNA’s information from nucleus to cytoplasm
Think of Messenger RNA as a "messenger carrying a message from DNA". Messenger RNA (mRNA) is made by DNA, as it's made it makes copies the DNA's instructions to make proteins and then carries these instructions out of the nucleus into the cytoplasm where it finds a ribosome.
They are single stranded templates (like half of a ladder) and they contain CODONS. Messenger RNA is the ONLY RNA that carries those codons.

12. Transfer RNA (tRNA)
Single chain of about 80 RNA nucleotides folded into a hairpin shape that bind to
specific amino
acids
There are 45
different varieties

13. Ribosomal RNA (rRNA)
Consists of RNA nucleotides in globular form – most abundant RNA type
Along with proteins,
rRNA makes up the
ribosomes where
proteins are made

14. TRANSCRITION & TRANSLATION
So, exactly how does RNA carry genetic information from DNA to the cytosol where it can assemble proteins?
PROTEIN SYNTHESIS
TRANSCRITION & TRANSLATION

15. 2 Parts of Protein Synthesis
1. TRANSCRIPTION-mRNA is produced from DNA in the nucleus.
2. TRANSLATION-Takes place in the ribosome. mRNA is ‘read’ and amino acids are transferred into the growing chain of the protein by tRNA.

16. Transcription Part 1 of Protein Synthesis
Process by which genetic information is copied from
DNA to mRNA
An enzyme, RNA polymerase initiates transcription by binding to promoter regions on DNA
DNA molecule separates
Only one of the DNA strands acts as a template
A promoter is a regulatory region of DNA located upstream (towards the 5' region) of of a gene, providing a control point for regulated gene transcription.

17. Transcription RNA polymerase connects RNA bases to the growing
RNA strand
The same as when DNA is replicated but uracil is used instead of thymine
It continues until it reaches a termination signal

18. Transcription PROMOTER-beginning of the gene being transcribed.
TERMINATION SEQUENCE-end of the gene being transcribed. Tells the RNA polymerase “let go”.
A protein-coding gene consists of a promoter followed by the coding sequence for the protein and then a terminator.
The promoter is a base-pair sequence that specifies where transcription begins. The coding sequence is a base-pair sequence that includes coding information for the polypeptide chain specified by the gene. The terminator is a sequence that specifies the end of the mRNA transcript.

19. Do Now How is RNA different from DNA? What are the three types of RNA?
What is the purpose of Transcription?

20. Translation Part 2 of Protein Synthesis
WHAT ARE PROTEINS?
Proteins are polymers of amino acids
There are 20 different amino acids
The sequence of amino acids determines the structure of the protein
The function of the protein depends on its structure

21. Proteins:

22. Translation Part 2 of Protein Synthesis
The sequence of nucleotides in an mRNA strand is translated into a sequence of amino acids to make a protein
A series of 3 nucleotides (bases) on mRNA make a codon. A codon codes for one amino acid.
Messenger RNA is made up of 500 to 1000 nucleotides long. Each mRNA contains codons. CODONS are groups of 3 bases long. For example, if the nitrogen bases in RNA are adenine (A), Uracil (U), Guanine (G), and Cytosine (C), then a codon would look like: AAU, GUA, CCA, UGC, AUG. There could be more than 100 codons in each strand of mRNA.

23. Codons

24. Translation Part 2 of Protein Synthesis
There are 64 codons and only 20 amino acids, so several codons can code for the same amino acid
There are also a start codon (AUG) and stop codons (UAA, UAG, UGA

25. Check for Understanding:
3 mRNA bases = code for 1 amino acid
If you have 450 mRNA bases, how many amino acids would you code for?
How many codons would you have?

26. Translation Part 2 of Protein Synthesis
mRNA goes to ribosome and begins translation from start codon
As the ribosome reads each codon, the corresponding tRNA will come and match its anticodon to the correct codon.
The anticodon is complementary to and pairs up with a corresponding mRNA codon.

27. Translation Part 2 of Protein Synthesis
The amino acid carried by the tRNA will be linked to the prior amino acid in the chain. Ribosome reads the stop codon and the process stops.

28. Translation Part 2 of Protein Synthesis
A. mRNA moves out of the nucleus
B. mRNA goes to ribosomes ibosome attaches to start codon (AUG)
C. tRNA moves amino acids in cytosplam to ribosome
D. tRNA anticodon bases pair with codon and drag amino acid to add to polypeptide
E. Ribosome enzymes create peptide bonds between amino acids
F. Amino acids are added until stop codon is reached

30. Summary: Let’s watch protein synthesis in ACTION! Or here… Now Play
“Drag and Drop Protein Syntheisis”

32. BIOLOGY Chapter 11 (pgs 202 - 219)
Gene Expression
BIOLOGY
Chapter 11 (pgs )

33. BIG IDEAS
Cells use information in genes to build hundreds of different proteins, each with a unique function.
Not all proteins are required by the cell at one time.
By regulating gene expression, cells can control when a specific protein is made.

34. Gene Expression
Genome is the complete genetic material contained in an organism.
Gene expression is the activation of a gene that results in the formation of a protein.
A protein is produced only when it is needed.

35. Gene Expression For example:
When you drink cow’s milk, the presence of lactose stimulates the cells that line the small intestines to produce the enzyme lactase to help digest this disaccharide.

36. Gene Expression For example:
When you drink cow’s milk, the presence of lactose stimulates the cells that line the small intestines to produce the enzyme lactase to help digest this disaccharide.

37. Gene Expression