Bio 001 Exam 2

presence of dead pathogenicbacteria increases the conversion of harmless bacteria to pathogenic bacteria

4 groups - live harmless, live pathogenic, heat killed pathogenic, heat killed pathogenic + live harmless

live harmless, heat killed pathogenic = HEALTHY; live pathogenic, heat killed pathogenic + live harmless = DEAD

Info required for bacteria to cause pnemonia can be passed from dead to living bacteria (transformation) and is NOT destroyed by heat (boiling)

originally thought: the information required to create and maintain cells is stored in the form of ...

pathogenic -(boiled)-> heat killed pathogenic -(isolated cellular molecules)-> fluid with molecules from heat killed pathogenic bacteria; treated with enzyme that destroys protiens, RNA, or DNA; ALL flasks with live harmless bacteria (multiple per condition

RNA and DNA, DNA and protien = ALL dead; RNA and protien = ALL healthy

DNA is required for transformation of harmless bacteria to pathogenic bacteria (CANT be destroyed by boiling); Neither RNA nor protien neccessary for transformation of harmless bacteria to pathogenic bacteria

" structure has novel features which are of considerable biological interest"

info storage - passed onto next generation (cell division, reproduction)

multiple types and functions - act as information messages, help control when and what molecules are made in a cell (regulation), speed up reactions (ribozymes)

smaller molecules used to form nucleic acids

part of nucleotide: ribose (in RNA), deoxyribose (in DNA, missing 1 oxygen compared to ribose)

Cytosine (C), Guanine (G), Adenine (A), Uracil (U, in RNA only), Thymine (T, in DNA only)

covalent, connect nucleotides

phosphate group to hydroxyl group end

double strand helix

DNA, 2 stands go in opposite directions

DNA, nucleotide in strand

DNA, nucleotides that interact via hydrogen bonds

DNA: A always pairs with T (forms 2 hydrogen bonds), C always pairs with G (forms 3 hydrogen bonds)

DNA, more hydrogen bonds = stronger interactions between the strands

X-ray diffraction pattern suggested a helical structure with specific uniform diameter

chargaff: %A = %T, %C = %G

ONE chromosome (piece of DNA), circular shape, fewer total base pairs, NOT in nucleus, NOT wrapped around protiens

MULTIPLE chromosomes, more base pairs, linear (straight) shape, located in nucleus, wrapped around protiens

single stranded, have Uracil (U), have ribose monnosaccharide, have DIRECTION

RNA, nucleotides in strand connected by covalent ...

RNA: interact via hydrogen bonds, A pairs with U, C pairs with G

making a copy of ALL genetic info (DNA) once prior to cell division

specific sequence of DNA that encodes info to make a polypeptide or functional RNA

using information stored in DNA to make specific products (polypeptides or functional RNAs)

making an RNA copy of a gene (1st step in expressing ALL genes)

using mRNA to direct the formation of polypeptides, ONLY required for expression of genes that contain information to make protiens

DNA: permenant information storage, RNA: temporary message for expressing a particular gene

DNA replication, specific sequence of DNA to which protiens required to start relication attach

DNA replication, 1

DNA replication, Many, need more places to start = gets copied faster

DNA replication, both strands are copied at same time in both directions

DNA replication, where DNA opens up on one side if a replication bubble

DNA replication, requires a .. , new strands are complementary to template strand (interact via HYDROGEN BONDS)

DNA replication, formed in specific direction

DNA replication, toward replication fork, away from ORI

DNA replication, away from replication fork, toward ORI

DNA replication, unwinds DNA strands

DNA replication, DNA helicase, protect single-stranded DNA from being degraded by cellular enzymes that break phosphodiester bonds, help keep strands seperated

DNA replication, form new strands (HIGHLY accurate, able to proof read), 2 at each replication fork (because 2 template strands to copy), ONLY in 1 direction, REQUIRE a TEMPLATE DNA strand AND RNA primer to start new strand

DNA replication, short piece of DNA, formed by a specific enzyme, gets removed and replaced with DNA by other enzymes after new strand is started

DNA replication, links pieces of new strand togther by forming phosphodiester bonds

all the genetic information (DNA) in a cell

a piece of DNA (has many genes)

sequence of DNA that contains the information to make a functional product (protien or functional DNA)

Transcription, specific sequence of DNA that indicates start of gene (Start signal)

Transcription, specific sequence of DNA that marks end of gene (stop signal)

Transcription, contains information needed to make polypeptide chain

Transcription, mRNA is complementary to ... (so is the coding strand)

Transcription, enzymes that form RNA strands, ONLY form phosphate to hydroxyl

Transcription, link nucleotides in the new RNA strand

Transcription, between complementary nucleotides

1. RNA polymerase binds to promoter sequence
2. DNA helix must be opened to allow transcription
3. New RNA strand is formed from phosphate to hydroxyl group
4. RNA strand separates from DNA template as RNA polymerase travels along the gene sequence
5. RNA polymerase transcribes terminator sequence - signals RNA polymerase to stop
6. RNA polymerase releases DNA and RNA, can transcribe this gene (or a different one), gene is NOT changed (can be transcribed as many times as needed)

Transcription, Eukaryotic mRNA processing, add Cap and poly-A tail (help protect mRNAs from being degraded

Transcription, eukaryotic mRNA processing, pieces of RNA sequence NOT required for translation are removed

Transcription, ready for translation: leave nucleus via nuclear pores

3 nucleotides specify an amino acid

ONE codon corresponds to ONE amino acid

more than one codon for each amino acid

Translation, specifies start AND amino acid met

Translation, ALL specify stop (and NOT amino acids)

codons in mRNA: no nucleotides shared by codons, reduce change in polypeptide sequence

codons in mRNA: no nucleotides between codons

mRNAs are translated in specific direction

Translation, chains of amino acids connected by COVALENT BONDS, same structure and differenences come from R group (make is hydrophilic or hydrophobic, compostion AND order determines 3D shape, can change which R groups form noncovalent bonds)

Translation, adaptors between mRNA codons and amino acids, NONE with anticodon complementary to STOP codons (NO corresponding amino acid)

Translation, each type of tRNA is only attached to ONE type of amino acid

Translation, the 3 nucleotides of tRNA that interact with complementary mRNA codon (HYDROGEN BONDS between complementary nucleotides)

Translation, connect amino acids and tRNAs in cells

Translation, specific enzymes, accuracy of tRNA-amino acid pairing essential

Translation, specific enzymes, determine which correspond to which amino acid

Translation, complexes of protiens and RNAs that form polypeptides, help position mRNAs and tRNAs carrying amino acids, form COVALENT BONDS between amino acids

Translation, ribosome and 1st tRNA assemble at start codon

Translation, Polypeptide chain formed as ribosome moves along mRNA, moves from phosphate to hydroxyl
1. tRNA (attached to amino acid) with anticodon complementary to next mRNA codons interacts with mRNA
2. Met attached by COVALENT BOND to next amino acid (reaction catalyzed by rRNA)
3. Ribosome shifts one codon (toward hydroxyl group end)
REPEAT
4. Empty tRNA “ejected”

Translation, stop codon reached; components dissasemble

a permenant change in the DNA sequence of an organisms genome; random, NOT necessarily harmful, sources of genetic diversity; DOES NOT always change the amino acid sequence of a polypeptide

change in ONE base-pair

substitution, changes to a codon that specifies the SAME amino acid, does NOT change amino acid sequence

substitution, alters a codon that corresponds to an amino acid (not the start codon) to a codon specifying a different amino acid; polypeptide still has same number of amino acids

substitution, changes a codon that specifies an amino acid to a stop codon

add or remove one or more nucleotides (can change how nucleotides are grouped into codons)

insetions and delections, aler how nucleotides are grouped into codons, can change ALL amino acids after the mutation, typically alter the polypeptides length (changes stop codon)

insert or delete 3 nucleotides