• Single nucleotide strand

• Sugar: Ribose• 4 Bases:

–A: Adenine–G: Guanine–C: Cytosine–U: Uracil

• U replaces T• Three Types of RNA

• mRNA

• Function: Copies the DNA code and moves to a ribosome

• Link between DNA & Protein

• Allows ribosome to create a protein

• Location: Starts in nucleus… moves to ribosome

• tRNA• Function: Transfers amino acids from the cytoplasm to

the ribosome• Ribosome will link amino acids together to form a protein• Location: Cytoplasm

Amino acidProline

Amino acidSerine

• rRNA• Function:

components of ribosomes

Transcription• Defined: Process of making mRNA from DNA

• Step 1: RNA Polymerase separates the DNA nucleotides

• Step 2: Free floating RNA nucleotides match with the DNA

Reminder: U replaces T

• Step 3: mRNA breaks free in separate pieces

• Step 4: mRNA processing takes place

– Unused portions (introns) are removed and the used portions (exons) bond together

• Step 5: Final mRNA strand travels to ribosome

• Step 6: DNA recombines to be used again

U|

G|C|A|A|G|U|C|A|U|U|C|

G|

Transcription Animation

Transcription Video

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DNA vs. RNA• Double Stranded

• Sugar: Deoxyribose

• Bases: A T C G

• Location: Nucleus

• Single strand

• Sugar: Ribose

• Bases: A U C G

• Location: Nucleus & Cytoplasm

Review• Name three different ways that DNA and RNA differ.• Which RNA:

– is found inside the nucleus?– transports amino acids to the ribosome?– exits the nucleus to the ribosome?– copies the DNA code?– makes up the structure of ribosomes?

• Perform transcription by using the following piece of DNA. Introns are underlined. Write the final strand of mRNA created.

T A C C G T A C A A T G G G A T C