Protein Synthesis ch 17

Protein Synthesis ch 10

Dont you just love eukaryotic cells?Central DogmaFlow of information:

DNA _____ Protein transcriptionhttp://www.stolaf.edu/people/giannini/flashanimat/molgenetics/transcription.swf

Transcription

1. initiation2. elongation3. termination

Transcription zooming intranscriptionhttp://highered.mcgraw-hill.com/sites/0072507470/student_view0/chapter3/animation__mrna_synthesis__transcription___quiz_2_.html

transcriptionhttp://www-class.unl.edu/biochem/gp2/m_biology/animation/gene/gene_a2.html

RNA processing animationhttp://www.sinauer.com/cooper/4e/animations0702.htmlAdditions:5 cap prevents fraying, attachment point for ribosomesPoly A tail prevents fraying, helps mRNA exit nucleusRNA splicing:Introns out (snRNP)Exons spliced together

Snurps

Purpose of introns?Lengthens chromosomes Regulatory role

Translationhttp://highered.mcgraw-hill.com/sites/0072507470/student_view0/chapter3/animation__protein_synthesis__quiz_3_.html

rRNA - _________________

mRNA - _________________Codon - ____________________________________

tRNA - _________________Anticodon - _________________________________Amino acid - ________________________________Peptide bond - ____________________________________

Its the secret code!Translation

TranslationInitiation: the ______ attaches to the ribosome and begins translation.

TranslationElongation: the polypeptide chain continues to ____.

TranslationTermination: The polypeptide has been completed and ________ from the ribosome.

Its believed that the code evolved very early in history of life.Why?___________________________________

Transplanting genesPolysomesSeveral __________can translate an mRNA at the same ______, forming what is called a polysome.

Signal peptides

A great summary graphic of protein synthesis in eukaryotic cellsProkaryotic Cells & Protein Synthesis

Mutations

Point mutation- an alteration in a single base pair

Insertions / deletions cause frameshift mutations

Mutagen agents which cause mutation1) "high energy" radiation - ultraviolet light (200 - 400 nm). - x-rays2) Reactive Chemicals - (Industrial Pollution)3) Chemicals from smokingTypes of point Mutations1) Base Substitutions -One base is substituted for another in the sequence of DNA nucleotides.Possible Consequences:Silent mutation - Lethal mutation -

Types of point Mutations2) Base Insertions and Deletions - base pair is removed or added to the DNA sequence. causes a frame shift = shift in the _______ ________ of the _____. Not all mutations are bad.What if the altered protein shape turns out to be BETTER at carrying on the chemical reaction its designed for?.Some mutations are beneficial.