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Fredrick Griffith

"transforming factor" is the genetic material
studied two forms/strains of bacterial species. (pneumonia.) harmless and deadly. deadly became harmless when heated. important discovery came when he mixed heat treated deadly and harmless i to a mouse and the mouse died.

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Oswald Avery

built off of griffith discovery. concluded protein could not be the transforming factor. said that DNA is the genetic material of a cell.

treated griffiths mixture of heat treated deadly strain and live harmless protein destroying enzymes. the bacterial colonies grown from the mixture were still transformed

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Alfred Hershey and Martha Chase

Convinced the science world that DNA is the transforming factor. concluded that phages DNA entered the bacterial cell during infections. DNA must carry the genetic informstion.

did more experiments to prove DNA was the hereditary material. used a batch of infecting phages and mixed it with radioactive isotopes of sulfur to label only the phages protein coats. in another batch they used radioactive isotopes of phosphorus to label DNA. USED A BLENDER.

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virus

a oackage of nucleic acid wrapped in a protein coat. not made of cells. can only reproduce by infecting another living cell.

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bacteripphage

a virus that infects bacteria

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transforming factor

DNA

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radioactive isotopes

an atom with an unstable nucleus

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deoxyribose

ring shaped sugar found in nucleotides

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nucleotide

building blocks (the monomers) of nucleic acid polymers

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nitrogenous base

a single or double ring of carbon and nitrogen atoms with functional groups

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deoxyribonucleic acid (DNA)

where heritable genetic information of an organism is stored. a polymer built of monomers called nucleotides.

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what is the structure of a single nucleotide?

ring shaped sugar called deoxyribose
a phosphate group
a nitrogenous base (single or double ring of carbon)

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four nitrogenous bases found in DNA

Adenine (A)
Thymine (T)
Cytosine (C)
Guanine (G)

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Adenine

bonds with Thymine in DNA
bonds with Uricel in RNA
double ring structure (purine)

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what are the purines?

Adenine and Guanine

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what is a purine?

larger, double ring structures

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what is a Pyrimidine?

single ring structures

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what are the pyrimidines?

cytosine and thymine

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Thymine

single ringed (pyrimidine)
bonds with Adenine in DNA
not found in RNA
replaced with Uracil in RNA

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Cytosine

single ringed (pyrimidine)
bonds with guanine in DNA

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Guanine

double ringed (purine)
bonds with cytosine

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Maurice Wilkins and Rosalind Franklin

showed that the basic structure of DNA was a helix. photographed DNA using crystallography

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Xray Crystallography

scattered xrays through the DNA crystal to form an image

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James Watson and Francis Crick

modeled DNA structure. Used franklins work to create a new model with two strands of nucleotides DOUBLE HELIX. hypothesized nitrogous bases aligned

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Double Helix

a twisting shape

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DNA replication

process of copying the DNA molecule

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antiparallel

DNA runs in opposite directions
Watson and crick ideas

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template

a place where it starts

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DNA polymerases

enzymes that make covalent bonds between the nucleotides of the new DNA strand

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genotype

an organisms genotype is its genetic make up. a sequence of nucleotide bases in its DNA

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phenotype

the organism's specific traits which lies in proteins and their wide variety of functions

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Chargaff

found the base pair rule

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base pair rule

a goes with t
c goes with g

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Ribonucleic Acid(RNA)

any nucleic acid whose sugar is ribose rather than the deoxyribose of DNA

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Differences between DNA and RNA

DNA is a double helix, RNA is a single strand
DNA uses deoxyribose, RNA uses ribose
DNA doesn't use Uracil, RNA does

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Uracil

very similar to thymine
pyrimidine
pairs with adenine in RNA

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gene

unit of inherited information in DNA

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transcription

DNA's nucleotide sequence is converted to the single stranded RNA molecule

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translation

converts nucleic acid language to amino acid language

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codon

codes for one amino acid

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how many types of ribonucleic acid (RNA)

3

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what are the three kinds of RNA

Messenger RNA (mRNA)
transfer RNA (tRNA)
ribosomal RNA (rRNA)

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Messenger RNA (mRNA)

transcribed from a DNA template.

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RNA polymerase

links the RNA nucleotides together

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introns

internal noncoding regions

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peptide bond

bond between amino acids

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polypeptide

many bonds which makes a protein

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telomeres

end of a chromosome that has dna that never gets turned into a protein. protects dna as replicated

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telomerase

enzyme that protects telomeres

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Linus Pauling

Cal tech professor that was close to figuring out the structure of DNA

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polymerase

enzyme that makes DNA or RNA

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Why does DNA need to be converted to RNA?

DNA cant leave the nucleolus.

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Why do genes become proteins?

genes are units of instructions in DNA taht explain how the protein should be made

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what is the difference between a gene and DNA

a gene is within the all together dna

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exon

what from dna in the nucleus is used in the copy

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intron

unneeded parts that stay in the nucleus

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helicase

enzyme that separates dna so it can be copied

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Ribosomal RNA (rRNA)

RNA that goes into the ribosome

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transfer RNA (tRNA)

rna that folds that travels to the ribosome

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start codon

AUG. tells where to start

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stop codon

UC tells to stop

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mutation

any change in the nucleotide sequence of DNA

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base substitution

the replacement of one base or nucleotide with another

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why are base substitutions sometimes harmless?

because in genetic code, several amino acids have more than one codon that code for the same amino acid

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silent mutation

a change where no change in the protein product would result

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base insertion

addition of nucleotides

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base deletion

subtracting a nucleotide

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why is insertion or deletion of one or more nucleotides in a gene harmful?

because mRNA is read as a series of triplets, adding or subtracting nucleotides may alter the triplet groupings of the genetic message. this will cause them to be regrouped into different codons and will result in a different or non working protein

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what causes mutations?

when errors occur in DNA replication

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mutagens

physical or chemical agents that cause mutations

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trisomy

3 chromosomes instead of 2

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nondisjunction

event during meiosis in which homologous chromosomes fail to seperate

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duplication

when part of a chromosome is repeated

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deletion

occurs when a fragment of a chromosome is lost

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inversion

reversing a fragment of the original chromosome

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translocation

when a fragment of a chromosome attaches to a non-homologous chromosome

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who was down syndrome named after

john langdon down

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cri du chat

babies cry like a cat

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ultrasound

sound waves to make an image

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klienfelters

is the set of symptoms resulting from additional X genetic material in males

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turners

missing an x chromosome in females

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amniocentesis

babies fluid is tested for chromosomal disorders

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karyotypes

the number and visual appearance of the chromosomes in the cell nuclei of an organism or species.

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tools to diagnose

karyotype, amniocentesis, ultrasound