1. Notes: RNA (pg. 5) RNA – Ribonucleic Acid
RNA is a messenger between the DNA & the ribosome. Its job is to help in the process of making proteins.

2. The Structure of RNA
RNA like DNA is made up of a long chain of nucleotides.
Each nucleotide is made up of 3 parts
ribose – a 5 carbon sugar
A phosphate group
A nitrogenous base

3. There are three major differences between RNA and DNA
The sugar in RNA is ribose. In DNA the sugar is deoxyribose
RNA is made up of a single strand of nucleotides; DNA is made up of two strands (double helix).
Three of the nitrogenous bases are the same (guanine, adenine and cytosine) except for one: DNA uses thymine where as RNA uses Uracil.

4. DNA vs. RNA

5. Transcription – the process in which a molecule of DNA is copied into a complementary strand of RNA. The result is a single strand of RNA (therefore it is not an exact copy of the DNA)… Very much like replication, but instead of making DNA, RNA is made.

6. There are three main types of RNA
messenger RNA (mRNA)– is the carrier of the genetic information from the DNA in the nucleus to the ribosomes in the cytoplasm.
The DNA cannot leave the nucleus; therefore something has to deliver the genetic code to the ribosomes (like the mailman).
mRNA

7. ribosomal RNA (rRNA) combines with proteins to make up the ribosome.
Made up of two subunits that snap together around the mRNA.
rRNA (& protein)

8. T= TRANSFER AND TRANSLATE
transfer RNA (tRNA) is the complement to the mRNA.
Its job is to translate a recipe for a protein from one language (nucleic acids or RNA) into another (amino acids).
T= TRANSFER
AND TRANSLATE
tRNA

9. 3 types of RNA:

10. Notes: Protein Synthesis (pg. 7-8)
Protein Synthesis is the joining of Amino Acids in a specific sequence in order to form a protein or polypeptide.
PROTEIN SYNTHESIS
= TRANSCRIPTION +
TRANSLATION

11. There are only 20 different amino acids normally found in most humans.
Essential amino acids must be eaten because the body cannot manufacture them.
Non-essential amino acids can be produced by the body from other amino acids.

12. Proteins can be 100’s to 1000’s of amino acids long.
The order of the amino acids also affects which protein is made.
The DNA (through the mRNA) will tell the ribosome exactly what protein must be made.

13. (not in packet…) If there is a mistake in the DNA, called a mutation
then it is likely that there will be a problem with the protein that it wants to produce.
For someone that has Sickle Cell Anemia, one letter in their instructions for making
hemoglobin is wrong. The end result is defective red blood cells.

14. First Step = Transcription
First step of protein synthesis, which occurs in the nucleus.
A complementary strand of mRNA is formed from a strand of DNA.

15. Second Step = Translation
Second step of protein synthesis, which happens at the ribosome.
Since the ribosome doesn’t understand the message sent from the DNA, it requires a translator (tRNA).
The tRNA ‘translates’ the message of the mRNA into amino acids.
The tRNA also picks up a specific amino acid in the cytoplasm and ‘travels’ to the mRNA (which is attached to the ribosome).

16. TRANSLATION CONT.
At the ribosome the mRNA is "read" in groups of three also known as codons. .
The tRNA is also read in groups of three, also known as anticodons.
Fill in chart!

18. UAC AUG UUC AAG DNA mRNA (codon) tRNA (anticodon) Amino Acid TAC
Methionine
AAG
Phenylalanine
UAC
AUG
UUC
AAG

19. Making mRNA from the DNA is called transcription.
When the anticodon pairs up with the codon it is called translation.

20. Diagram of Protein Synthesis (Transcription + Translation)
Label
Name A B
Label
Name C D E F G H
ribosome
NUCLEUS
tRNA
CYTOPLASM
anticodon
codon
mRNA
Amino Acids