DNAChapter 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 _________ Leth

al 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 ____________ ____________ ____________ ____________