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... • When mRNA leaves nucleus it has a blueprint of DNA’s instructions. • mRNA goes to ribosomes in cytoplasm • Ribosomes read the blueprint on mRNA. ...
Section 1: Nucleic acids – the molecules of life
Section 1: Nucleic acids – the molecules of life

... replications, one medium and one light band was produced . 1st generation – all the DNA was hybrid (contained one heavy and one light strand), this produced the middle bond . 2nd generation – half the DNA is hybrid (one light and one heavy strand) and the other half is light DNA (top band) The Genet ...
Ch 16+ 17 Reading Guide
Ch 16+ 17 Reading Guide

... 1. Describe Beadle and Tatum's experiments with Neurospora and explain the contribution they made to our understanding of how genes control metabolism. 2. Explain how RNA differs from DNA. 3. Distinguish between transcription and translation. 4. Define “codon” and explain the relationship between th ...
SBI-4U1 Exam Review
SBI-4U1 Exam Review

... 2. What is ATP, and how does it provide energy for cellular processes? Adenosine triphosphate. Primary energy-providing molecule in a cell. Energy is released by hydrolyzing the bond between the 2nd and 3rd phosphate groups. 3. What are oxidation and reduction? Give (general) examples of each. Oxida ...
Human Genomics ppt
Human Genomics ppt

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...  The vector must be specific to the host cell. -Expression from bacterial cell typically done to obtain nonglycosylated mammalian protein  The promoter allows efficient transcription of the inserted gene and the operator permits regulation.  The ribosome-binding site provides sequence signals for ...
SBI-4U1 Exam Review
SBI-4U1 Exam Review

... 2. What is ATP, and how does it provide energy for cellular processes? Adenosine triphosphate. Primary energy-providing molecule in a cell. Energy is released by hydrolyzing the bond between the 2nd and 3rd phosphate groups. 3. What are oxidation and reduction? Give (general) examples of each. Oxida ...
Exam3-1406_Spring'06.doc
Exam3-1406_Spring'06.doc

... E) the backbones of the molecule. 16) It became apparent to Watson and Crick after completion of their model that DNA molecule could carry a vast amount of hereditary information in its A) sequence of bases. B) phosphate-sugar backbone. C) complementary base pairing. D) side groups of nitrogenous ba ...
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Ch - TeacherWeb

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... • In protein production there are codons that will indicate to the ribosome when to start and when to end. • Once the chain of up to several hundreds of amino acids is completed, the process stops and the protein gets sent to the endoplasmic reticulum to be packed and released. • The order of amino ...
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... activities that are involved in transcriptional regulatory mechanisms (Struhl, 1998). In particular, classical transcriptional activation and repression mechanisms involve the targeted recruitment of chromatin-modifying activities to specific genes, whereupon they create local domains of histone mod ...
CS374 - Stanford University
CS374 - Stanford University

... throwing the virus into a predesigned protein soup that contained all the polymerases and other enzymatic ingredients necessary for RNA transcription and translation. The synthetic virus was able to successfully replicate itself from this mixture.” ...
Teacher quality grant
Teacher quality grant

... DNA. In eukaryotes, this information can be found in the nucleus of virtually every cell. Eukaryotic cell Nucleus CHROMOSOME One or more unique pieces of DNA—circular in prokaryotes, linear in eukaryotes—that together make up an organism's genome. Chromosomes vary in length and can consist of hundre ...
DNA - Gulf Coast State College
DNA - Gulf Coast State College

... DNA. In eukaryotes, this information can be found in the nucleus of virtually every cell. Eukaryotic cell Nucleus CHROMOSOME One or more unique pieces of DNA—circular in prokaryotes, linear in eukaryotes—that together make up an organism's genome. Chromosomes vary in length and can consist of hundre ...
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... Magnetic Beads for the binding step, in which DNA binds to the beads. Wash steps then disposed of proteins, cell debris and other contaminants, while the DNA bound to the magnetic beads was transferred through the steps. The DNA was eluted into the Elution Buffer. In certain cases, e.g. cultured cel ...
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Nucleosome



A nucleosome is a basic unit of DNA packaging in eukaryotes, consisting of a segment of DNA wound in sequence around eight histone protein cores. This structure is often compared to thread wrapped around a spool.Nucleosomes form the fundamental repeating units of eukaryotic chromatin, which is used to pack the large eukaryotic genomes into the nucleus while still ensuring appropriate access to it (in mammalian cells approximately 2 m of linear DNA have to be packed into a nucleus of roughly 10 µm diameter). Nucleosomes are folded through a series of successively higher order structures to eventually form a chromosome; this both compacts DNA and creates an added layer of regulatory control, which ensures correct gene expression. Nucleosomes are thought to carry epigenetically inherited information in the form of covalent modifications of their core histones.Nucleosomes were observed as particles in the electron microscope by Don and Ada Olins and their existence and structure (as histone octamers surrounded by approximately 200 base pairs of DNA) were proposed by Roger Kornberg. The role of the nucleosome as a general gene repressor was demonstrated by Lorch et al. in vitro and by Han and Grunstein in vivo.The nucleosome core particle consists of approximately 147 base pairs of DNA wrapped in 1.67 left-handed superhelical turns around a histone octamer consisting of 2 copies each of the core histones H2A, H2B, H3, and H4. Core particles are connected by stretches of ""linker DNA"", which can be up to about 80 bp long. Technically, a nucleosome is defined as the core particle plus one of these linker regions; however the word is often synonymous with the core particle. Genome-wide nucleosome positioning maps are now available for many model organisms including mouse liver and brain.Linker histones such as H1 and its isoforms are involved in chromatin compaction and sit at the base of the nucleosome near the DNA entry and exit binding to the linker region of the DNA. Non-condensed nucleosomes without the linker histone resemble ""beads on a string of DNA"" under an electron microscope.In contrast to most eukaryotic cells, mature sperm cells largely use protamines to package their genomic DNA, most likely to achieve an even higher packaging ratio. Histone equivalents and a simplified chromatin structure have also been found in Archea, suggesting that eukaryotes are not the only organisms that use nucleosomes.
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