Transcription and translation
1 / 20

Transcription and Translation - PowerPoint PPT Presentation

  • Uploaded on

Transcription and Translation. Oh so amazing…. The big QUESTION:. How does a GENE on a CHROMOSOME in the NUCLEUS in the CELL in your BODY make…. a trait? 1 st step: The DNA in our body must be decoded into RNA. Decoding messages:. DNA. RNA. Long chain of nucleotides 5-carbon sugar RIBOSE

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about ' Transcription and Translation' - livia

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

The big question

  • How does a GENE on a CHROMOSOME in the NUCLEUS in the CELL in your BODY make…. a trait?

  • 1st step: The DNA in our body must be decoded into RNA

Decoding messages
Decoding messages:



Long chain of nucleotides

5-carbon sugar RIBOSE

Phosphate group

Nitrogenous base

Single stranded

Uracil instead of thymine

  • Long chain of nucleotides

  • 5-carbon sugar DEOXYRIBOSE

  • Phosphate group

  • Nitrogenous base

  • DOUBLE stranded

  • Thymine

Types of rna
Types of RNA

See the board

transcription translation

Types of rna1
Types of RNA

Transcription and translation


  • Transcription= copying part of the DNA sequence into a complementary sequence in RNA

  • RNA Polymerase: enzyme binds to promoter regions, specific sequences

  • Let’s try:



Ok so far we have a strand of rna
Ok so far we have…a strand of RNA

  • Next big question: How does RNA make a protein (which leads to a trait)?

    • We must understand the genetic code

    • There are 20 amino acids that occur naturally

    • Amino acids are the monomers of a protein

    • Proteins are made by joining amino acids to make a POLYPEPTIDE chain

    • The properties of the protein are determined by this specific amino acid sequence


  • A codon= three nucleotides in a row that correspond to a specific amino acid!

  • Figure 12-7…a good friend to you.

Now we have some codons
Now we have…some codons

  • Next Big question: How do we make a protein out of a bunch of mRNA codons?

  • Translation: the comeback of the ribosome

  • Translation= decoding the message from mRNA (the codons) into a polypeptide chain


  • The cell goes through a lot of trouble to synthesize proteins correctly because they:

    • Define what cell looks like

    • Define how it functions

    • How it makes enzymes

    • How it moves

    • How it provides support

    • How it regulates life processes…..whew!

Step 1 translation
Step 1: Translation

  • Like we did before, the mRNA message must be transcribed from the DNA in the nucleus

  • The mRNA is released from the nucleus to the cytoplasm

  • U’s replace T’s! Don’t forget!

Step 2 translation1
Step 2: Translation

  • mRNA attaches to the ribosome

  • Codons move through the ribosome

  • As it moves through, the proper amino acid is brought to the ribosome by the tRNA

  • The tRNA attaches the amino acid to the growing polypeptide chain

  • It knows which one to fetch because it has the ANTICODON- like velcro.

Step 3 translation
Step 3: Translation

  • The ribosome forms peptide bonds between amino acids

  • At the same time, ribosome breaks bond with tRNA

  • Continues to grow until a stop codon is reached

  • Releases the polypeptide

Genes and proteins
Genes and Proteins

  • STILL…what do proteins have to do with hair color, eye color, lactose intolerance etc?

  • Many proteins are enzymes

  • Enzymes control pigment production

  • Enzymes control antigens in blood type

  • Enzymes control rate and pattern of growth