protein synthesis transcription and translation n.
Skip this Video
Loading SlideShow in 5 Seconds..
Protein Synthesis Transcription and Translation PowerPoint Presentation
Download Presentation
Protein Synthesis Transcription and Translation

Loading in 2 Seconds...

play fullscreen
1 / 25

Protein Synthesis Transcription and Translation - PowerPoint PPT Presentation

  • Uploaded on

Protein Synthesis Transcription and Translation. 8.4 and 8.5. Bell Work. 1. A structure in the nucleus of the cell consisting of one long strand of DNA that is tightly coiled 2. Provides blueprint for synthesis of proteins

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 'Protein Synthesis Transcription and Translation' - honorato-mcgowan

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
bell work
Bell Work
  • 1. A structure in the nucleus of the cell consisting of one long strand of DNA that is tightly coiled
  • 2. Provides blueprint for synthesis of proteins
  • 3. A specific location on a chromosome, consisting of segments of DNA, that codes for a specific protein
  • 4. List two nucleic acids.
  • 5. List the three parts of a nucleotide.
  • 6. Which sugar does RNA contain?
  • 7. Which sugar does DNA contain?
  • 8. List the four bases that RNA has.
  • 9. List the four bases that DNA has.
  • 10. Which molecule has the shape of a double helix?
  • 11. What happens during DNA replication?
  • 12. When does DNA replication occur?
focus questions
Focus Questions
  • What is protein synthesis?
  • Define transcription and explain the process.
  • What is the function of mRNA?
what is protein synthesis
What is protein synthesis?
  • Protein synthesis -
    • Making proteins
rna carries dna s instructions
RNA carries DNA’s instructions.
  • The central dogma states that information flows in one direction from DNA to RNA to proteins.




  • The central dogma includes three processes.
  • Replication
  • Transcription
  • Translation
  • RNA is a link between DNA and proteins.
what is transcription
What is transcription?
  • The process by which the DNA is copied to make a strand of RNA
  • Through this process the DNA code is transferred out of the nucleus to the ribosome
transcription how does it happen

transcription complex

start site


Transcription- How does it happen?
  • An enzyme attaches to the exact location on the DNA molecule where the gene is found, causing the two strands of DNA to separate at that location.


  • Complementary RNA nucleotide bases bond to the bases on one of the separated DNA strands.


A bonds with U

T bonds with A

C bonds with G

G bonds with C



  • Nucleotides of RNA bond together, forming a single-stranded molecule of RNA that peels away from the DNA strand and the two DNA strands rejoin. This is called messenger RNA (mRNA).
  • The messenger RNA leaves the nucleus
try this transcribe the message
Try This: Transcribe the message
  • Use the DNA code to make a complementary strand of mRNA.
  • Questions
  • 1. What is made during transcription?
  • 2. Where does the mRNA go after transcription?
more practice with transcription
More Practice with transcription
  • Go to class web page.
  • Click on link for Build a Protein.
  • Make the mRNA.
  • Get signature of teacher in lab notebook.
  • Stop for now.
8 5 focus questions
8.5 Focus Questions
  • 1. Define translation.
  • 2. How is messenger RNA involved in translation? What is a codon? Distinguish start and stop codons. How are the codons related to the amino acids?
  • 3. How is transfer RNA involved in translation? What is an anticodon? Draw a diagram and label the parts of tRNA.
  • 4. Summarize the steps of translation.
amino acids are coded by mrna base sequences
Amino acids are coded by mRNA base sequences.
  • Translation is the process of interpreting the genetic message and building proteins.
describe the messenger rna mrna

codon for

methionine (Met)

codon for

leucine (Leu)

Describe the messenger RNA (mRNA)
  • Carries the genetic message to the ribosome
  • A codon is a sequence of three nucleotides
  • Each codon specifies a specific amino acid that will be placed in a chain to build a protein.
  • The sequence of mRNA nucleotides determines the order of amino acids and which protein is produced

The genetic code matches each RNA codon with its amino acid or function.

  • The genetic code matches each codon to its amino acid or function.
  • three stop codons
  • one start codon, codes for methionine

Describe the transfer RNA (tRNA)

  • Transfer RNA (tRNA)
    • tRNA transfers the amino acid into the correct sequence
    • There are 20 different types of tRNA (one for each amino acid)
    • At one end is the anticodon site that is complementary to mRNA codon
    • At the other end is the specific amino acid
how are ribosomes involved
How are Ribosomes involved?
  • Translation begins when the mRNA attaches to the ribosome.
  • The ribosomes contain proteins and ribosomal RNA (rRNA)

Ribosomes consist of two subunits.

  • The large subunit has three binding sites for tRNA.
  • The small subunit binds to mRNA.

The tRNAbinds to a start codon and signals the ribosome to assemble.

    • A complementary tRNA molecule binds to the next exposed codon, bringing its amino acid close to the first amino acid.

The now empty tRNA molecule exits the ribosome to pick up another amino acid.

  • A complementary tRNA molecule binds to the next exposed codon.
  • The process ends once the stop codon is reached.