DNA Chapter 12

DNA  Holds our ______________ ______________  Like a ______________  Important for ______________ to occur  Biologists had to discover the chemical nature of _________ to determine that it is responsible for our genetic information

Griffith and Transformation  Transformation: when a strain of bacteria is ____________ by a gene or genes from ______________ bacteria  Experiment  Inject mice with bacteria containing virus for ______________  Smooth colonies = have ______________ ______________  Rough colonies = harmless bacteria

Griffith and Transformation  If the virulent colonies were killed with ________ and mixed with ______________ bacteria, then the harmless bacteria get ______________ into virulent bacteria  Some factor of the bacteria was ______________ to harmless bacteria

Avery and DNA  Wanted to repeat Griffith’s experiment  Treated heat-killed virulent bacteria with ______________  One enzyme destroyed __________ and ______________  Another enzyme destroyed ONLY _________ Lethal Virus

Avery and DNA  Results showed that bacteria treated with DNA destroying enzyme did ______ ______________ harmless bacteria into virulent bacteria  It is the ______ that stores the genetic information from one generation to the next Lethal Lethal Non Lethal Lethal Virus

Hershey-Chase  Bacteriophage: a _________ that infects ______________ ONLY  Scientists wanted to see what gets injected into a bacteria to ___________ infection  Used a ______________ marker for DNA and protein

Hershey Chase  After infection, the bacteria that had radioactive marker on DNA showed that it is the _______ that is ____________ into the bacteria  Results: _______ from the ____________ is what causes infection

DNA Structure  Monomer of DNA is a ____________  ____________ __________  ________________ group  ________________ base  4 Nitrogenous bases in DNA  ____________

DNA Structure  Backbone of DNA is the ________ and ____________  Nitrogenous bases stick out of side to form __________ rungs  These bases are repeated in a ____________ that form our genetic code

DNA Structure  Chargaff’s Rule  Scientist that discovered a ____________ between the 4 bases  Same percentage of ____________ as ____________  Same percentage of ____________ as Cyto ____________ sine  Scientists still not sure how they match up though

DNA Structure  Rosalind Franklin  Scientist that worked with ____________ ____________  Used ____________ on a portion of DNA and the results showed an _____pattern

DNA Structure  Watson & Crick  Scientists that were able to ____________ Rosalind’s X-ray picture  Result: DNA has a __________ __________ pattern where the nitrogenous bases face each other

DNA Structure  DNA has a double helix pattern  Looks like a ____________ twisted up  The sides of the ladder are the ____________ and ____________ and the rungs of the ladder are the ____________ ____________ paired up  The ____________ binds to thymine  The guanine binds to ____________  This concluded Chargaffs’s rule  ____________ ____________

DNA and Chromosomes  Prokaryotes  Lack ____________ and ____________  DNA floats as a ____________ in the cytoplasm  Eukaryotes  _______ times more DNA than prokaryotes  DNA is located in ____________  Specific number of chromosomes  Ex: Humans have _____ chromosomes

DNA and Chromosomes  DNA Length  DNA is very ____________  DNA is coiled up into a very small space because it is in ____________ form  Chromosome Structure  Tightly packed chromatin is wrapped around small proteins called ____________  When chromatin gets super coiled you create a ____________

DNA Replication  Each strand of DNA is needed to be a ____________ for a new strand of DNA to be produced  Since you can use one strand to make the other side, they are said to be _______________

Duplicating DNA  Before mitosis occurs, DNA needs to be duplicated first during ____________  When DNA duplicates, its called ________________  DNA molecules separates into two strands, then produces two new ____________ strands following the rules of _______ ____________  Each strand serves as a ____________ for the new strand

How Replication Occurs  Enzymes help make new strands of DNA  One enzyme called ____________ “unzips” the DNA, ____________ the base pairs  _______ ____________ adds new bases to pair up with the template  This enzyme also ____________ to make sure everything matches  What would be the matching bases to the part of DNA shown below?

RNA & Protein Synthesis Sections 3-4

Structure of RNA  Made of ____________  ____________ differences between DNA & RNA  ____________  DNA = ________________ sugar  RNA = ____________ sugar  RNA is ____________ stranded  RNA uses ____________ instead of ____________ to bond with Adenine

Types of RNA  Three types of RNA  mRNA  ____________ RNA  rRNA  ____________ RNA  tRNA  ____________ RNA

Types of RNA  Messenger RNA  This is a copy of __________________ strand of DNA  Eventually will ____________ for a ____________ to be made

Types of RNA  Ribosomal RNA  RNA found in ____________ (organelles in the cell)  Ribosomes are the ____________ for protein synthesis

Types of RNA  Transfer RNA  Help produce a ____________ from mRNA  Brings ____________ ________ (monomer of protein) to ribosome to bond them together and make a whole protein

Transcription  Taking DNA and making an RNA copy  Occurs in the cell’s ____________  ______ ____________ opens the DNA and adds RNA copy to the template  Once this is made it is called _______________

RNA Editing  Pre-mRNA is a ________ ________ to the final copy of mRNA  Some parts of pre-mRNA are not needed to make a protein  These unnecessary parts are called ____________  Introns get _______ _______ of pre-mRNA  Before leaving the nucleus, mRNA needs to get a ______ and _______ to finalize the RNA strand

The Genetic Code  Proteins are made of 20 possible ____________ ____________  In order to make a protein from a strand of mRNA, the mRNA is read in a 3 letter sequence called ____________

The Genetic Code  Each three letter codon represents an amino acid  DNA = AGCGTGCCA  RNA =  Codons =  Amino acids =

The Genetic Code  RNA knows when to ____________ and ____________ based on the codons read  There is ________ start codon: _______  There are ____________ stop codons: _______, _______, _______

Translation  Taking mRNA and making a ____________  Occurs in the cytoplasm on a ____________  ____________ brings specific __________ _________ to ribosome  If mRNA = AUG, then tRNA = UAC  The tRNA has the ________________

Translation  As new tRNA brings amino acids to the ribosome, past ones break off leaving just amino acids ____________ to each other  This continues until one of the three ____________ codons is met  Finished amino acid strand goes through ____________ ____________

Mutations  ____________ in the DNA sequence that affect the cell  Two types of mutations  ____________ ____________  _________________ ____________

Gene Mutation  Point mutation  A change in ____nucleotide in a DNA sequence  Occur only in a ____________ point of the DNA  Can ____________ be a problem  Frameshift mutation  A change in the ____________ ____________ of DNA  Since DNA is read in 3 letter codons, if there is an ____________, ____________, or large ____________ in these codons the ____________ is changed

Chromosomal Mutation  A change in the number of ____________ in the cell  Four types  ____________