• Study Resource
  • Explore Categories
    • Arts & Humanities
    • Business
    • Engineering & Technology
    • Foreign Language
    • History
    • Math
    • Science
    • Social Science

    Top subcategories

    • Advanced Math
    • Algebra
    • Basic Math
    • Calculus
    • Geometry
    • Linear Algebra
    • Pre-Algebra
    • Pre-Calculus
    • Statistics And Probability
    • Trigonometry
    • other →

    Top subcategories

    • Astronomy
    • Astrophysics
    • Biology
    • Chemistry
    • Earth Science
    • Environmental Science
    • Health Science
    • Physics
    • other →

    Top subcategories

    • Anthropology
    • Law
    • Political Science
    • Psychology
    • Sociology
    • other →

    Top subcategories

    • Accounting
    • Economics
    • Finance
    • Management
    • other →

    Top subcategories

    • Aerospace Engineering
    • Bioengineering
    • Chemical Engineering
    • Civil Engineering
    • Computer Science
    • Electrical Engineering
    • Industrial Engineering
    • Mechanical Engineering
    • Web Design
    • other →

    Top subcategories

    • Architecture
    • Communications
    • English
    • Gender Studies
    • Music
    • Performing Arts
    • Philosophy
    • Religious Studies
    • Writing
    • other →

    Top subcategories

    • Ancient History
    • European History
    • US History
    • World History
    • other →

    Top subcategories

    • Croatian
    • Czech
    • Finnish
    • Greek
    • Hindi
    • Japanese
    • Korean
    • Persian
    • Swedish
    • Turkish
    • other →
 
Profile Documents Logout
Upload
Genetic Transfer in Bacteria
Genetic Transfer in Bacteria

... The genes that control conjugation are contained in the tra region of the plasmid . Many genes in the tra region have to do with the synthesis of a surface structure, the sex pilus . Only donor cells have these pili, The pili make specific contact with a receptor on the recipient and then retract, p ...
Chapter 20 - Biotechnology
Chapter 20 - Biotechnology

... By doing more mixing and matching of modular elements, humans - and vertebrates in general - reach more complexity than flies or worms. – The typical human gene probably specifies at least two or three different polypeptides by using different combinations of exons. • Along with this is additional p ...
G - AP Bio Take 5
G - AP Bio Take 5

... From Gene to Protein ...
BIO105 Learning objectives for test 3 Topic: The Cell cycle and
BIO105 Learning objectives for test 3 Topic: The Cell cycle and

... After attending lecture, reviewing their notes, and reading the chapter, a student should be able to: - Explain how RNA differs from DNA. - In their own words, briefly explain how information flows from gene to protein. - Distinguish between transcription and translation. - Describe where transcript ...
File - singhscience
File - singhscience

Genetic Engineering
Genetic Engineering

... genetic information in the cell starts at DNA, which replicates to form more DNA. Information is then ‘transcribed” into RNA, and then it is “translated” into protein. The proteins do most of the work in the cell. Once information gets into protein, it can't flow back to nucleic acid. ...
Reading Packet 5- Molecular Genetics Part 1 Chapter 16
Reading Packet 5- Molecular Genetics Part 1 Chapter 16

... 30. What do the genes on an R plasmid allow a bacterium to do? Why is this a problem for humans? ...
Question about phospholipids:
Question about phospholipids:

... If the role of this enzyme is to cleave DNA and RNA, why does it make sense that Arginine (R) and Histidine (H) are two of the amino acids important for binding the substrate? R and H both have positively charged sidechains. It makes sense that they would be able to form interactions with the negati ...
University of Wollongong - Research Network for Metals in Medicine
University of Wollongong - Research Network for Metals in Medicine

Blueprint for life - Siemens Science Day
Blueprint for life - Siemens Science Day

Problem Set 2
Problem Set 2

... (b) As stated above, it is known that these residues are important for binding or catalysis. You want to test for which of these functions (binding or catalysis) the amino acids Arg78 and His 110 is important. To perform this test you change Arg78 and His110 to different amino acids and then monitor ...
Mastering Biology Genetics Retake
Mastering Biology Genetics Retake

... 4) Changing bacteria so they are able to produce human proteins. _____________ 5) Growing starfish from cut pieces. _____________________________ ...
DNA - Mrs-Lamberts-Biology
DNA - Mrs-Lamberts-Biology

...  The structure and purpose of DNA & RNA  We will investigate 3 major processes that involve DNA & RNA A. Semiconservative replication= the process of copying/doubling the amount of DNA prior to cell division so the daughter cells both get a full set. The next two processes occur back to back, and ...
Field Guide to Methylation Methods
Field Guide to Methylation Methods

Lab #5a Mr. Green Genes-DNA Sequence
Lab #5a Mr. Green Genes-DNA Sequence

... The efficient analysis of biological data to reveal useful information has become one of the most daunting challenges facing biologists. In the twenty years since 1995, when the first complete genome sequence was submitted to the databases, technology improvements have dramatically decreased the cos ...
DNA Replication
DNA Replication

... create four strands of DNA • One original strand (daughter strand) will be attached to an older strand (parental strand) • This means that DNA conserved through the process of DNA replication ...
Document
Document

... 13- …………….blocks the MRNA transcription. a. Repressor protein. b. Inducer. c. RNA polymerase. d. All of the above are correct. 14- Initiation, elongation and termination are the stages of………... a. Polymerase action. b. DNA transcription. c. Protein synthesis. d. DNA replication. ...
Protein Synthesis
Protein Synthesis

... • A ribosome becomes attached to one end of the mRNA molecule about to be translated. • Inside the ribosome, there are sites that tRNA molecules can attach to, which allows the anticodon to line up with the mRNA codon. • As this happens along the molecule, it allows amino acids to line up and become ...
CLARK LAP Wednesday March 26 2014 STRAWBERRY DNA
CLARK LAP Wednesday March 26 2014 STRAWBERRY DNA

... function, and is so important that this complex compound is found in virtually every one of its cells. In this activity you’ll make your own DNA extraction kit from household chemicals and use it to separate DNA from strawberries. 
 
 Background
 Whether you’re a human, rat, tomato or bacterium, eac ...
Question How does DNA control a cell?By controlling Protein
Question How does DNA control a cell?By controlling Protein

... Genetic Code Sequence ...
What is DNA sequencing
What is DNA sequencing

... Both the Maxam-Gilbert and Sanger-Coulson methods can only produce about 400 bases of sequence at a time. Most genes are larger than this. To sequence a large DNA molecule it is cut up (using two or more different restriction enzymes) into different fragments and each fragment is sequenced in turn 1 ...
Engineering of diffraction-quality crystals of the NF-κB
Engineering of diffraction-quality crystals of the NF-κB

... of human N F - K B P50, 14 mostly charged residues comprising the NLS, are invisible in the electron density maps. Tyr-351 in human N F - K B P50 (Tyr-326 in N F - K B P52) is the last residue involved in secondary structure interactions of the C-terminal Ig-domain (P-strand g). We suspected that an ...
DNA Fingerprinting
DNA Fingerprinting

... transgenic foods 2. People with allergies cannot be sure if they will have a reaction. ...
Bioreg2017_Replication3_V4
Bioreg2017_Replication3_V4

Camp 1 - UCSC Directory of individual web sites
Camp 1 - UCSC Directory of individual web sites

... • For the 15 amino acids coded for by 2, 3, or 4 triplets, it is only the third letter of the codon that varies. Gly, for example, is coded for by GGA, GGG, GGC, and GGU. • The code is almost universal: it the same in viruses, prokaryotes, and eukaryotes; the only exceptions are some codons in mitoc ...
< 1 ... 101 102 103 104 105 106 107 108 109 ... 285 >

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.
  • studyres.com © 2025
  • DMCA
  • Privacy
  • Terms
  • Report