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Smooth ER - Home - KSU Faculty Member websites
Smooth ER - Home - KSU Faculty Member websites

... A typical eukaryotic chromosome contians 1 to 20 cm of DNA. During metaphase of meiosis/mitosis, this DNA is package into a chromosome with a length of only 1 to 10 mm (a condensation of almost 104-fold in length from the naked DNA molecule). ...
BA13.00
BA13.00

... • Mapping the genome of a species allows scientists to identify beneficial and harmful genes in a population, and is the first step in determining the location of specific genes on chromosomes. – Changes in the genome of a species occur slowly in response to environmental changes. ...
DNA PPT
DNA PPT

...  RNA found in ribosomes (organelles in the cell) ...
Genetics
Genetics

... 87. In DNA profiling, what are used to cut DNA strands into fragments? 88. Give two applications (uses) of DNA profiling. 89. Name the plant from which you isolated DNA in your practical studies. 90. For what precise purpose did you use freezer-cold ethanol (alcohol) in your isolation of DNA? 91. Pr ...
Extraction of DNA from an Onion
Extraction of DNA from an Onion

... Extraction of DNA from an Onion Molecular biologists and biochemists are involved with research in finding out as much as possible about the DNA in plants and animals. Although DNA was discovered in the 1950’s, there still remains a lot to be known about it, especially how it is used to determine th ...
Document
Document

... • Restriction enzymes act as “scissors” by cutting DNA – allow scientists to more easily study and manipulate ...
Week 4 Pre-Lecture Slides
Week 4 Pre-Lecture Slides

5о end of mRNA 1 2 1 1 2 3 Protein Ribosome RNA
5о end of mRNA 1 2 1 1 2 3 Protein Ribosome RNA

... Create a random stretch of protein-coding DNA. Flip a coin, and if heads imagine that the promoter is on the left (and add the DNA needed to encode a start codon there as well). Pick any single base, and predict the mutation class: –  If you remove the base –  If you replace the base with two As –  ...
Exploring Genes
Exploring Genes

... Exploring Genes Recombinant Technololgy ...
Macromolecules - Essentials Education
Macromolecules - Essentials Education

... poypeptides usually make up a protein. They can also code for the production of an RNA molecule.   ...
DNA
DNA

... • Red or green spots indicate a large excess of mRNA from one or the other sample, while yellow spots show that the amount of this specific mRNA was roughly equal. • Very low amounts of both mRNA samples result in dark spots. • Further, the intensities can be quantified and used for constructing clu ...
Random-priming in vitro recombination: an effective tool for directed evolution ,
Random-priming in vitro recombination: an effective tool for directed evolution ,

... beneficial mutations and removal of deleterious ones (2–4). The sequence diversity upon which recombination acts can be obtained by mutating the wild-type gene or, alternatively, by using homologous genes isolated from nature or obtained in parallel laboratory evolution experiments (e.g. genes optim ...
Note: all of these sentences are true.
Note: all of these sentences are true.

... 39.Telomerase is unique because it contains an RNA molecule and protein that acts as a revers transcriptase. 40. The function of Telomerase at the telomere it adds new DNA to the longer strand of the telomere overhang. 41.Telomeres are shortened slightly after every round of replication or cell div ...
The Molecular - MolGen | RuG
The Molecular - MolGen | RuG

... the laboratory of biochemist Erwin Chargaff. It was already known that DNA is a polymer of nucleotides, each consisting of three components: a nitrogenous (nitrogen-containing) base, a pentose sugar called deoxyribose, and a phosphate group (Figure 16.5). The base can be adenine (A), thymine (T), gu ...
3D structures of RNA
3D structures of RNA

PTC Lab Classroom Slides
PTC Lab Classroom Slides

... What you’ll need: ...
More on Genetics
More on Genetics

... The DNA fragments are separated according to size using gel electrophoresis. The fragments containing repeats are then labeled using radioactive probes. This produces a series of bands—the DNA fingerprint. ...
Document
Document

... the folds of unsolved proteins as well as designing new proteins to cure diseases. We’re collecting data to find out if humans' pattern-recognition and puzzle-solving abilities make them more efficient than existing computer programs at pattern-folding tasks. If this turns out to be true, we can the ...
Using a Single-Nucleotide Polymorphism to Predict
Using a Single-Nucleotide Polymorphism to Predict

... To confirm that viable DNA was extracted and that negative GM result isn’t due to a non-viable template. Use highly conserved chloroplast gene from Photosystem II – part of the light reaction of photosynthesis. ...
PowerPoint Notes
PowerPoint Notes

... each serve as a template for making a new strand, shown in yellow. Replication results in two daughter DNA molecules, each consisting of one original strand and one new strand. ...
Document
Document

... - lactose metabolism • lactose not present: repressor active, operon off; no transcription for lactose enzymes • lactose present: repressor inactive, operon on; inducer molecule inactivates protein repressor (allolactose) ...
practice exam 3_answer key
practice exam 3_answer key

... c. sister chromatids are attached to one another d. centrioles are located e. chromosomes are grouped during telophase 10. What is a sister chromatid? a. a chromosome found outside the nucleus b. a special region that holds two centromeres together c. another name for the chromosomes found in geneti ...
Lecture 19A. DNA computing
Lecture 19A. DNA computing

... assemble the entire organism. The amount of information involved requires the individual DNA strands to be extremely long. Each cell contains about 3 cm of DNA. The fact that this long molecule fits into a cell of around a few microns across is because DNA is very thin (2 nm in diameter). ...
eprint_12_13279_954
eprint_12_13279_954

... an and the interaction with its environment, make up its phenotype. The order of DNA bases constitutes the bacterium's genotype. A particular organism may possess alternate forms of some genes.Such alternate forms of genes are referred to as alleles. The cell's genome is stored in chromosomes, which ...
lecture_ch05_2014 honors biology_website
lecture_ch05_2014 honors biology_website

... Take-home message 5.5 The process by which this information is used to build an organism occurs in two ...
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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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