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Protein Synthesis. The formation of proteins based on information in DNA and carried out by RNA. (Gene expression). Flow of Genetic Information: DNA “unzips” Transcription- makes RNA Translation- makes protein. DNA Review questions. What is the shape of DNA? What are the monomers?
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Protein Synthesis The formation of proteins based on information in DNA and carried out by RNA. (Gene expression) Flow of Genetic Information: DNA “unzips” Transcription- makes RNA Translation- makes protein
DNA Review questions • What is the shape of DNA? • What are the monomers? • List the three parts that make up the monomers. • What type of bonds holds the parts of the monomer together? • What type of bonds hold the two strands of DNA together? • Where is DNA found in eukaryotic cells? • What is Chargaff’s rule? • What is the process in which more DNA is made? • What breaks the bonds between the nitrogen bases for this process to occur? • When during the cell cycle does this process occur? • What form is DNA found when the cell is not dividing? When it is dividing?
3 Types of RNA • Messenger RNA (mRNA) • Ribosomal RNA (rRNA) • Transfer RNA (tRNA)
Messenger RNA (mRNA) • Carries the instructionsfrom DNA
Transfer RNA (tRNA) • Transfers amino acids to the ribosome to make a protein • Has 3 nucleotides on one end (anticodon) and the corresponding amino acid on the other (codon).
Ribosomal RNA (rRNA) • Make up Ribosomes
Transcription mRNA • The process by which ______ is made from part of the ______sequence that codes for a protein (gene) • Transcription is taking the original (master) blueprint DNAand making _______ in the form of RNA • This RNA blueprint will be used to assemble _________ DNA copies proteins
Steps of Transcription enzyme • An ______, RNA polymerase unzips the DNA molecule at the region of the gene that is being transcribed • Free _____________ form base pairs with their complementary nucleotides on the DNA strand • mRNA threads away and the _____ strand rejoins • mRNA leaves the _______ and goes to the cytoplasm (__________) DNA - RNA A - U T - A C - G G - C RNA nucleotides DNA nucleus ribosome
A Codonis a group of 3 nucleotides in mRNA that specifies an ___________ (building blocks of protein) • Think of the ______ as the drawings on the blueprint for the genetic code amino acid codon
What would the RNA strand read if the DNA strand read: • AGC TAA CCG • UCG AUU GGC
Definition of Translation mRNA • Use the codonof _______ to specify the sequence of amino acids to build a _____ • It is time for the Blueprint (DNA-mRNA) to be read • The Blueprint (______) is sent to the construction site (________) • Decoding of the genetic instructions protein mRNA ribosome
Steps of Translation mRNA CodonAnti-codon mRNAtRNA A - U U - A G - C • ______ arrives at the Ribosome • tRNA __________ are complementary to the mRNA ________ • tRNApicks up an __________ • _____ delivers the amino acid to the ___________ • Amino acids are assembled into polypeptide chains, to form ______, held together with peptide bonds anti-codons codon amino acid tRNA ribosome proteins
When the mRNA is first transcribed, there are long sequences of ___________ that are not required for the synthesis of the protein called _____. The DNA sequences that code for the protein are known as ______. Introns are edited out (cut out) of the mRNA before it leaves the nucleus and the remaining ______ are spliced together to form the final mRNA nucleotides introns exons exons
Protein Synthesis Video Protein Synthesis Video
Mutation change in the DNA sequence GENETIC MUTATIONS (pp. 307-308) A mutation is a________________________. Although many mutations are harmful, some mutations are _________, and others may be very ____________ to an organism. There are two categories of mutations: A. Chromosomal Mutations A chromosomal mutation involves a change in the ______________ of the entire chromosome or a change in the total ____________ of chromosomes. Does not alter individual ________. These errors generally occur during _____________ or ____________. silent beneficial structure number genes mitosis meiosis
Gene Mutations: A gene mutation is a change in one gene on an individual chromosome. This may result in a change in only one _________ or many nucleotides making up that gene might be altered. The incidence of gene mutations is relatively low due to the action of _________ that _________ the DNA sequence after __________.There are two types of gene mutations: nucleotide enzymes proofread replication
nucleotides • Point Mutations – This is a change in one or just a few ___________, but the total number of nucleotides in the gene is notchanged. This might have no effect, or change one amino acid. Therefore, the resulting ________ may or may not be altered. 2. Frameshift Mutations – This involves the __________ or __________ of a ____________. When a nucleotide is inserted or deleted, this shifts the reading of the remainder of the ________; therefore, the ___________ of the remainder of the mRNA is altered. This will usually result in tremendous changes in the _______________ chain and completed protein. protein deletion addition nucleotide translation codons amino acid