3.5+Transcription+and+translation

3 Chemistry of Life - 3.1 Chemical elements and water - 3.2 Carbohydrates, proteins and lipids - 3.3 DNA structure - 3.4 DNA replication - 3.5 Transcription and translation - 3.6 Enzymes - 3.7 Cell respiration - 3.8 Photosynthesis - Biochemistry Labs - DNA Labs

3.5 //(and 7.3, 7.4)// Transcription and translation
// N.B. This topic links to 7.3 Transcription and 7.4 Translation which HL students will be studying in conjunction with this topic. This page contains both Core and AHL content. AHL specific content is written in italics. //


 * Starters**
 * What makes a firefly's tail glow?
 * DNA, Hot Pockets, & The Longest Word Ever
 * What is the //central dogma of molecular biology//? Research and summarise in a short sentence. Who first came up with the dogma?


 * Assessment statements** (IBO notes added to some points to clearly indicate what needs to be understood and what does not)
 * 3.5.1 || Compare the structure of RNA and DNA. Limit this to the names of sugars, bases and the number of strands. ||
 * 3.5.2 || Outline DNA transcription in terms of the formation of an RNA strand complementary to the DNA strand by RNA polymerase. ||
 * 3.5.3 || Describe the genetic code in terms of codons composed of triplets of bases. ||
 * 3.5.4 || Explain the process of translation, leading to polypeptide formation. Include the roles of messenger RNA (mRNA), transfer RNA (tRNA), codons, anticodons, ribosomes and amino acids. ||
 * 3.5.5 || Discuss the relationship between one gene and one polypeptide. Originally, it was assumed that one gene would invariably code for one polypeptide, but many exceptions have been discovered. ||


 * //7.3.1// || //State that transcription is carried out in a 5' -> 3' direction.// ||
 * //7.3.2// || //Distinguish between the sense and antisense strands of DNA.// ||
 * //7.3.3// || //Explain the process of transcription in prokaryotes, including the role of the promoter region, RNA polymerase, nucleoside triphosphates and the terminator.// ||
 * //7.3.4// || //State that eukaryotic RNA needs the removal of introns to form mature mRNA. Further details of the process of post-transcriptional modification of RNA are not required.// ||


 * //7.4.1// || //Explain that each tRNA molecule is recognized by a tRNA-activating enzyme that binds a specific amino acid to the tRNA, using ATP for energy.// ||
 * //7.4.2// || //Outline the structure of ribosomes, including protein and RNA composition, large and small subunits, three tRNA binding sites and mRNA binding sites.// ||
 * //7.4.3// || //State that translation consists of initiation, elongation, translocation and termination.// ||
 * //7.4.4// || //State that translation occurs in a 5' -> 3' direction.// ||
 * //7.4.5// || //Draw and label a diagram showing the structure of a peptide bond between two amino acids.// ||
 * //7.4.6// || //Explain the process of translation, including ribosomes, polysomes, start codons and stop codons.// ||
 * //7.4.7// || //State that free ribosomes synthesize proteins for use primarily within the cell, and that bound ribosomes synthesize proteins primarily for secretion or for lysosomes.// ||

Learn first through doing try the paper based simulation from Serendip Studio on transcription and translation. The links can be found under DNA Labs.
 * The approach**

Another good starting point is the Welcome Trust animation showing the synthesis of insulin

Next download and complete the BioK notes to review and complete your understanding. media type="custom" key="23828662"

Lastly try some of the review questions (coming soon) with closed books to test your understanding.

An alternative set of notes from i-Biology can be found here __ SL content only __ media type="custom" key="23828664" __ //AHL content - complete SL first// __ media type="custom" key="23828666"
 * Other workbooks and worksheets **

Learn by doing is an important reinforcement for this topic. Use the learn.genetics Transcribe and Translate simulation to walk through both processes.
 * Presentations and tutorials **



Steven Taylor ([|i-Biology]) has a great presentation to view and take notes from before starting your notebook media type="custom" key="23828670" media type="custom" key="23828672"

Use the teaching and visualization animations from St Olaf to gain an overview of:
 * transcription
 * translation

Very good DP Bio specific video tutorials from [|C4B] 3.5.1 Comparing DNA and RNA media type="custom" key="23828674" 3.5.2 Transcription media type="custom" key="23828676" 3.5.3 Genetic code media type="custom" key="23828678" 3.5.4 Translation media type="custom" key="23828684"

__Sense vs. Anti-sense__ The sense strand (coding strand) has the same base sequence as mRNA with uracil instead of thymine. The antisense (template) strand is transcribed.
 * Key Points**

DNA and Genetics is fast evolving area of Biological research. One of the very interesting areas of current research is Epigenetics. How does this fit in with what you know about DNA and how is it contrary to accepted theory? (n.b. this goes beyond your assessment statements). media type="custom" key="23828686"
 * TOK**

Good animations from [|HHMI] on transcription and translation
 * Useful Links **

Practise your understanding using the dicatation exercise from i-Biology media type="custom" key="24971090"