Term
| Griffith wanting to figure how u got pneumonia |
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Definition
made 2 observations:
- disease causing strain of bacteria grew into smooth colonies on culture plates
- the harmless strain grew into colonies with rough edges
in 4th experiment he mixed heat-killed, disease-causing bacteria with live, harmless bacteria and injected into mice who developed pneumonia and died. so griffith concluded that heat-killed bacteria passed their disease-causing ability to harmless strain |
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Definition
| griffith called his conclusion as a result of transformation- one strain of bacteria had changed permanently . hypothesized a factor must contain info that could change harmless bacteria into disease-causing ones |
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Definition
| scientist avery treated bacteria with enzymes that could kill protein, lipids, carbs, and nucleic acid, but transformation still occurred. then they used DNA breaking enzymes- no transformation soo the nucleic acid that DNA stores and transmits the genetic info from one generation to the next- transforming factor |
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Term
| Hershey- Chase experiment |
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Definition
| studied viruses. concluded that genetic material of bacteriophage was DNA, not protein |
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Term
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Definition
| a virus that infects bacteria. composed of DNA or RNA core and protein coat. which part, protein or DNA, made genes?? |
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Term
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Definition
| DNA is made of nucleotides. is a monomer of nucleic acids made up of a five carbon sugar called deoxyribose, a phosphate group, and a nitrogenous base. backbone of DNA chain is formed by sugar and phosphate groups of each nucleotide. nucleotides can be joined together in any orger |
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Term
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Definition
1. adenine
2. guanine
3. cytosine
4. thymine
*percentages of Cytosine and Guanine are equal in DNA samples
*percentages of Adenine and Thymine are equal in DNA samples
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Term
double helix
(Rosalind Franklin/ Watson and Crick) |
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Definition
| model of DNA was a double helix, in which 2 strands were wound around each other |
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Term
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Definition
| discovered that hydrogen bonds can form only between certain base pairs- adenine and thymine (AT) and guanine and cytosine (CG) |
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Term
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Definition
| in cytoplasm. have single DNA molecule with genetic info |
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Term
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Definition
| 1000 times amount of DNA as prokaryotes. located in cell nucleus. number of chromosomes varies. |
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Term
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Definition
| eukaryotic chromosomes contain DNA and protein, tightly packed to form chromatin |
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Term
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Definition
| chromatin consists of DNA tightly coiled around proteins called histones |
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Definition
| DNA and histone molecules form nucleosomes. nucleosomes pack together, forming thick fiber. |
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Definition
| sites where separation and replication occur |
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Term
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Definition
| each strand of the DNA double helix has all the info needed to reconstruct the other half by the mechanism of base pairing |
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Term
| during DNA replication... |
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Definition
| the DNA molecule separates into 2 strands, then produces 2 new complimentary strands following the rules of base pairing. each strand of the double helix of DNA serves as a template for the new strand. |
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Term
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Definition
| principle enzyme involved in DNA replication. joins individual nucleotides to produce a DNA molecule and then "proofreads" each new DNA strand (physically grabs new pieces to finish/ add on for replication) |
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Definition
| coded DNA instructions that control the production of proteins |
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Term
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Definition
| can be decoded by copying part of the nucleotide sequence from DNA to RNA |
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Term
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Definition
| contains coded info for making proteins. consists of a long chain of nucleotides (nucleotide= 5 carbon sugar, phosphate group, and nitrogenous base) |
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Term
| 3 main differences between DNA and RNA |
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Definition
1. sugar in RNA is ribose instead of deoxyribose
2. RNA is generally single stranded
3. RNA contains uracil in place of thymine |
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Term
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Definition
1. messenger RNA
2. ribosomal RNA
3. transfer RNA |
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Term
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Definition
| carries copies of instructions for assembling amino acids into proteins |
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Term
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Definition
| ribosomes are made up of proteins and ribosomal RNA |
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Term
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Definition
| during protein construction, transfer RNA transfers each amino acid to the ribosome |
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Term
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Definition
| RNA molecules are produced by copying part of a nucleotide sequence of DNA into a complementary sequence in RNA. requires the enzyme, RNA polymerase. during transcription, RNA polymerase binds DNA and separates DNA strands . RNA polymerase then uses one strand of DNA as a template from which nucleotides are assembled into a strand of RNA |
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Term
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Definition
| DNA of eukaryotic genes contains sequences of nucleotides called introns (extra), that are not involved in coding for proteins |
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Term
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Definition
| DNA sequences that code for proteins (important and actually used) |
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Term
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Definition
| language of mRNA instructions. uses four letters (A, U, C, G) |
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Term
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Definition
| consists of 3 consecutive nucleotides on mRNA that specify a particular amino acid that is to be placed on the polypeptide chain. some amino acids can be specified by more than one codon. AUG= start codon. there are also stop codons. |
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Term
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Definition
| decoding of an mRNA message into a polypeptide chain (protein). takes place on ribosomes. during translation, the cell uses info from messenger RNA to produce proteins. mRNA transcribed in nucleus, enters cytoplasm, attaches to ribosome, codons of mRNA move thru ribosome, proper amino acid brought to ribosome by tRNA, amino acid transferred to growing polypeptide chain, tRNA molecules carry one kind of amino acid with 3 unpaired bases. these bases called anticodon are complementary to one mRNA codon. ribosome binds new tRNA molecules and amino acids as it moves along the mRNA, process continues until ribosome reaches stop codon. |
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Term
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Definition
| enzyme will only bind to regions of DNA, promoters, which have specific base sequences |
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Term
| genes contain instructions for assembling... |
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Definition
| proteins, many of which are enzymes that catalyze and regulate chemical reactions. proteins are specifically designed to build or operate a component of a living cell. sequence of bases in DNA us used as template in mRNA. codons of mRNA specify sequence of amino acids in protein. |
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Term
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Definition
| changes in genetic material |
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Term
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Definition
| mutations that produce changes in asingle gene |
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Term
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Definition
mutations that produce changes in whole chromosomes
- deletions
- duplications
- inversions
- translocations |
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Term
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Definition
| gene mutations involving change in one or a few nucleotides are called point mutations cuz they occur at a single point in DNA sequence. include substitutions, deletions, and insertions |
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Term
| affects of substitutions, deletions, and insertions |
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Definition
substitutions- affect no more than a single amino acid
insertion and deletions- more dramatic cuz they cause shifts in the grouping of codons |
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Term
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Definition
may change every amino acid that follows the point of mutation. can alter a protein so much that it is unable to perform its normal functions
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Term
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Definition
| produce extra copies of parts of a chormosome |
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Term
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Definition
insertion= an extra base is inserted to base sequence
deletion= loss of a single base is deleted and the reading frame is shifted |
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Term
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Definition
| reverse the direction of parts of chromosomes |
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Definition
| occurs when part of one chromosome breaks off and attaches to another |
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Definition
| condition in which an organism has extra sets of chromosomes |
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Term
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Definition
| group of genes that operate together. must be turned on and off. |
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Term
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Definition
| in the promoter (P) region, RNA polymerase binds and then begins transcription- turns on |
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Term
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Definition
| other region, operator (O), when repressor binds to O region, transcription not possible- turns off |
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Term
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Definition
changes shape and falls off the operator and turns on again- transcription possible
many genes regulated by repressors
some genes use proteins that speed transcription. sometimes regulation occurs at level of protein synthesis. |
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Term
| operons are not generally found in |
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Definition
| eukaryotes- have more complex and individual regulatory sequences |
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Term
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Definition
| many eukaryotic genes have a sequence called TATA box- seems to help position RNA polymerase. promoters found just before it |
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Term
| some DNA binding proteins enhance transcription by: |
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Definition
- opening up tightly packed chromatin
- helping to attract RNA polymerase
- blocking access to genes |
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Term
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Definition
| as cells grow and divide, they undergo differentiation, meaning they become specialized in structure and function |
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Term
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Definition
| control the differentiation of cells and tissues in the embryo. careful control of expression in hox genes is essential for normal development. all hox genes are descended from genes of common ancestors. |
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Term
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Definition
| group of 3 bases on a tRNA molecule that are complimentary to an mRNA codon |
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