page_content stringlengths 12 2.63M | metadata unknown |
|---|---|
Eng. Chem.*, 1942, *44*, 867
- 498. C,B. Havens, *N.B.S. Cicrular # 525*, 1953, 107
- 499. F.H. Winslow, W.O. Baker, and Y.A. Yager, *Proceeding of First and Second Carbon Conferences,* Univ. of Buffalo Press, 1956
- 500. N. Grassie, I.F. McLaren, and I.C. McNeill, *Eur. Polymer J.*, 1970, *6*, 679
- 501. N. Grassie, I... | {
"Header 1": "*9.9.12 Oxidation of Step-Growth Polymers*",
"token_count": 1975,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
} |
Shinohara, *J. Polymer Sci,* 1969, *B7*, 839
- 537. T. Takeshita, K. Tsuji, and T. Keiki, *J. Polymer Sci.,* 1972, *A-1,9*, 1411
- 538. K. Tsuji and T. Seiki, *J. Polymer Sci., Letters*, 1972, *10*, 139
- 539. D.J. Carlson and D.M. Wiles, *Macromolecules,* 1969, *2,* 587; 597
- 540. T. Kagiya and K. Takemoto, *J. Macro... | {
"Header 1": "*9.9.12 Oxidation of Step-Growth Polymers*",
"token_count": 1970,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
} |
K. Pielichowski; D. Bogdal, J, Pielichowski, A. Boron, *Thermochim. Acta* 1997, 307(2), 155
- 581. W.H. Starnes, Jr., H. Chung, B.J. Wojciechowski, D.E. Skillcorn, and G.M. Benedikt, *Am. Chem. Soc. Polymer Preprints,* 1993,(2), *34*, 114
- 582. J. Lacoste and Y. Israeli, *Am. Chem. Soc. Polymer Preprints,* 1993,(2), *... | {
"Header 1": "*9.9.12 Oxidation of Step-Growth Polymers*",
"token_count": 346,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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#### 10.1 Polymer Supports for Reagents, Catalysts, and Drug Release
Supports are materials that are used for immobilization of various reagents, catalysts, drugs for release. Many of them are specially prepared macromolecules. Reagents and catalysts on support find applications in organic syntheses, biochemical reac... | {
"Header 1": "Polymeric Materials for Special Applications",
"token_count": 2030,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Thus, it can be nitrated, chloromethylated, sulfonated, lithiated, carboxylated, and acylated. The greatest use has been made of the chloromethylated and lithiated derivatives. These two derivatives can react with nucleophilic and electrophilic reagents, respectively, resulting in a wide range of functionalized polymer... | {
"Header 1": "Polymeric Materials for Special Applications",
"token_count": 2011,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Following are two examples:
+ CH2CN
or + O O S O
Similar to the work by Frechet who grafted functional groups to heterogeneous polystyrene (see above), Hodges used living free-radical polymerization to prepare what he referred to as Rasta resin [\[23](#page-792-0)]. The Merrifield resin was first functionalized w... | {
"Header 1": "Polymeric Materials for Special Applications",
"token_count": 1077,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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$$\begin{array}{cccccccccccccccccccccccccccccccccccc$$
The resulting polymer was then converted to a rhodium hydrogenation catalyst:
$$(F - F)_{7}$$
$$(F - F)_{7}$$
$$(F - F)_{7}$$
$$(F - F)_{7}$$
$$(F - F)_{7}$$
$$(F - F)_{7}$$
$$(F - F)_{7}$$
$$(F - F)_{7}$$
$$(F - F)_{7}$$
$$(F - F)_{7}$$
$... | {
"Header 1": "Polymeric Materials for Special Applications",
"token_count": 1683,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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$$\begin{array}{c|c} O & & & \\ \hline \\ O & & N-H \\ \hline \\ O & & \\ \hline \\ O & & \\ \hline \\ O & & \\ \hline \\ O & & \\ \hline \\ O & & \\ \hline \\ O & & \\ \hline \\ O & & \\ \hline \\ O & & \\ \hline \\ O & & \\ \hline \\ O & & \\ \hline \\ O & & \\ \hline \\ O & & \\ \hline \\ O & & \\ \hline \\ O & & ... | {
"Header 1": "Polymeric Materials for Special Applications",
"token_count": 2048,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Following are examples of more prominent utilizations of support materials.
#### 10.1.3.1 Immobilized Catalysts
It may be more accurate to refer to many of them as catalysts attached to polymers. Such catalysts can be inorganic compounds, like, for instance, Lewis acids attached to organic polymers. They can also b... | {
"Header 1": "*10.1.3 Utilization of Support Materials*",
"token_count": 1937,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Additional improvements in performance were obtained when the catalyst was immobilized on a monolithic silica rods:
$$\begin{array}{c|c}
\hline
\\
O \\
O \\
\hline
\\
Cl \\
\\
PCy_3
\end{array}$$
#### 10.1.3.3 Immobilized Reagents
An example of such a reagent is use of immobilized triphenyl methyl lithium to tran... | {
"Header 1": "*10.1.3 Utilization of Support Materials*",
"token_count": 3216,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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This compares very favorably with a 27% yield obtainable without polymeric supports [[58](#page-793-0)].
Another example is benzoylation of d-butyrolactone. When an acylation reaction is being carried out on an ester in solution, the ester enolate must be completely formed before the acylating agent can be introduced... | {
"Header 1": "*10.1.3 Utilization of Support Materials*",
"token_count": 2040,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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The reaction can be illustrated as follows:
$$\begin{array}{c|ccccccccccccccccccccccccccccccccccc$$
Masuda and colleagues reported [\[71](#page-793-0)] that they synthesized poly(anthryacetylenes)-bearing oligo oxyethylene units by using a transition metal catalyst, WC1<sup>6</sup> , in 30 and 34% yields. The polym... | {
"Header 1": "*10.1.3 Utilization of Support Materials*",
"token_count": 2024,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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One of them is through a metathesis ring opening polymerization:
Shrock catalyst OSi(CH<sub>3</sub>)<sub>2</sub>C<sub>4</sub>H<sub>5</sub>
$$n + n HO - Si$$
The polymer can be doped with iodine, acids, and ferric chloride. Alkoxy-substituted poly(phenyl vinylene) is easier to oxidize and exhibits higher conductiv... | {
"Header 1": "*10.1.3 Utilization of Support Materials*",
"token_count": 1576,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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In order to better understand the emission and absorption of light by molecules, it is necessary to look at the quantum-mechanical concept of the nature of light. In this concept, light is considered to be a *beam of photons* whose energies are quantized. Detailed description of quantum mechanics and spectroscopy is be... | {
"Header 1": "*10.3.2 Quantum-Mechanical Description of Light*",
"token_count": 2048,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Solid lines represent electronic transitions. They are accompanied by absorption or emissions of photons. Radiationless transitions are represented by doted lines. The above diagram shows the lowest singlet state S<sup>1</sup> , where the electrons are spin-paired, and the lowest triplet state T<sup>1</sup> , where the... | {
"Header 1": "*10.3.2 Quantum-Mechanical Description of Light*",
"token_count": 1985,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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The increase in the energy of a molecule as a result of absorbing a quantum of radiation can be expressed in the relationship [\[85](#page-794-0)]:
$$\Delta E = hC/\lambda$$
where $\lambda$ is the wavelength of the interacting radiation. All reactions that are photochemical in nature involve electronically exci... | {
"Header 1": "*10.3.2 Quantum-Mechanical Description of Light*",
"token_count": 2033,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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In the first one, energy transfers result from the interactions of the dipole fields of the excited donors and ground state acceptor molecules (long-range: Forster (dipole–dipole)) [86, 90]. This is referred to as the *resonance transfer mechanism*. Such transfer is rapid when the extinction coefficients for absorption... | {
"Header 1": "*10.3.2 Quantum-Mechanical Description of Light*",
"token_count": 2011,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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The charge separation that occurs in such a photo-induced electron transfer provides a way to convert the excitation energy of the excited molecule to a chemical potential in the form of a radical ion pair.
Electron migration can also be a movement of an electron either to a neutral electron donor from an oxidized on... | {
"Header 1": "*10.3.2 Quantum-Mechanical Description of Light*",
"token_count": 2025,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Also, as mentioned earlier, folding of a polymer before excitation into such a conformation that the sensitizers are held within a hydrophobic pocket improves the efficiency of energy migration when a large number of intramolecular hops. Efficiency of energy migration is also helped through-bond interactions that inter... | {
"Header 1": "*10.3.2 Quantum-Mechanical Description of Light*",
"token_count": 2028,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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[10.3,](#page-725-0) can act in two ways, by energy transfer and by electron transfer. To be exact, one may feel that a true photosensitizer is one that acts by energy transfer alone. This, however, is not always the case. Also, in the event of electron transfer, the process can lead to photo-induced decomposition via ... | {
"Header 1": "*10.3.2 Quantum-Mechanical Description of Light*",
"token_count": 571,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Some photocross-linking of polymers can be traced back to ancient days, when pitch was photocrosslinked for decorative purposes [\[102](#page-794-0)]. In modern times, wide varieties of photocross-linkable polymers were developed. The early practice of photo imaging relied mainly upon the photodimerization reactions. T... | {
"Header 1": "10.5 Photocross-linkable Polymers",
"token_count": 1104,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Following is an illustration of some of these groups [111, 112]:
banzothiophene oxide coumarin
dibenzazepene
$$HO_2C$$
$N \oplus Y \ominus$
$R$
$SIIbazole$
$SIIbazole$
$SIIbene$
$SIIbene$
$SIIbene$
$SIIbene$
$SIIBENE$
$SIIBENE$
$SIIBENE$
$SIIBENE$
$SIIBENE$
$SIIBENE$
$SIIBENE$
$SIIBENE$
$SIIBENE$
$SIIBENE$
$SIIBE... | {
"Header 1": "10.5 Photocross-linkable Polymers",
"token_count": 2046,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Photocross-linking of poly(vinyl cinnamate) can include the following reactions [124]:
1. Truxinic acid type dimerization in irradiated poly(vinyl cinnamate) that can occur intramolecularly. It can be shown as follows:
This is accompanied by formation of both folded and parallel chains
2. Truxillic acid type inte... | {
"Header 1": "10.5 Photocross-linkable Polymers",
"token_count": 2026,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Dimerization, on the other hand, takes place more favorably in other polymers, including poly(vinyl cinnamate) [\[150](#page-795-0)].
The liquid crystals alignment in films prepared from materials with cinnamate group after irradiating the films with linearly polarized UV light is quite uniform. All the aggregate str... | {
"Header 1": "10.5 Photocross-linkable Polymers",
"token_count": 790,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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$$\bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \bigcap_{O} \big... | {
"Header 1": "10.5 Photocross-linkable Polymers",
"token_count": 2083,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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[\[155](#page-795-0)]. When the R group shown above is *p*-Br, *m*-NO2, or (CH3)2N, the cross-linking is via formation of biradicals derived from the double bonds of the cinnamoyl groups and an abstraction of protons from the neighboring methyne or methylene groups. This reaction of dimerization can be illustrated as f... | {
"Header 1": "10.5 Photocross-linkable Polymers",
"token_count": 1079,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Poly(vinylbenzyl abietate) in the film state is cross-linkable via photo-dimerization of the conjugated carbon-carbon double bonds of the abietic acid moieties [166]. What the photo-dimerization product looks like is not clear. Formation of a cyclobutane rings in photo-dimerization of steroids was represented as follow... | {
"Header 1": "10.5.6 Polymers with Pendant Abietate and Dibenzazepine Groups",
"token_count": 699,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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The aromatic azide groups photo-decompose into nitrenes when irradiated with UV light: The nitrenes, that form, possess two unpaired electrons, similarly to carbenes, and dimerize readily into *azo* groups
$$R \stackrel{\bigoplus}{\longrightarrow} \stackrel{\bigodot}{N} \stackrel{\bigodot}{\longrightarrow} UV \text{ ... | {
"Header 1": "*10.5.7 Polymers That Cross-link by Dimerization of Nitrenes and by Other Combinations of Free-Radicals to Form Covalent Bonds*",
"token_count": 1960,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Among these, photo-rearrangements from norbornadiene to quadricyclane and back are of considerable interest, because photo-energy can be stored as strain energy (about 96 kJ/mol) in a quadricyclane molecule and later recovered [\[184\]](#page-796-0)
This photo-isomerization reaction is... | {
"Header 1": "*10.5.7 Polymers That Cross-link by Dimerization of Nitrenes and by Other Combinations of Free-Radicals to Form Covalent Bonds*",
"token_count": 1693,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Two of them are conjugated homopolymers that are linked with a zinc porphyrin:
$$A = \begin{array}{c} \begin{array}{c} \begin{array}{c} \begin{array}{c} \\ \end{array} \\ \end{array} \\ B \end{array} = \begin{array}{c} \begin{array}{c} \\ \end{array} \\ \end{array} \\ \begin{array}{c} \\ \end{array} \\ \end{array} \\... | {
"Header 1": "*10.5.7 Polymers That Cross-link by Dimerization of Nitrenes and by Other Combinations of Free-Radicals to Form Covalent Bonds*",
"token_count": 2121,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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The polymer has a constant ratio of the zinc porphyrin to the incorporated monomer units, regardless of the molecular weight. The ratio of zinc porphyrin to the polymer blocks can be varied in the material by varying the size of the blocks A. Studies of energy transfer from the polymer to the zinc porphyrin showed that... | {
"Header 1": "*10.5.7 Polymers That Cross-link by Dimerization of Nitrenes and by Other Combinations of Free-Radicals to Form Covalent Bonds*",
"token_count": 2004,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Izumi and coworkers carried out similar preparations of conjugated polymers with azobenzenes in the main chain [[212,](#page-796-0) [213\]](#page-796-0). Application of various palladium-catalyzed coupling methods such as the Suzuki coupling and the Heck reactions allowed formation of poly(*p*-phenylene)- and poly(ph... | {
"Header 1": "*10.5.7 Polymers That Cross-link by Dimerization of Nitrenes and by Other Combinations of Free-Radicals to Form Covalent Bonds*",
"token_count": 1525,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Due to possible utilization of photo-induced orientation in polymeric films in optical data storage, this phenomenon and the quadratic nonlinear optical effects were extensively investigated in the last few years. It was reported, for instance, that to study photo-isomerization in a polymeric environment, a series of p... | {
"Header 1": "*10.6.4 Application to Optical Data Storage*",
"token_count": 449,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
} |
The relationship of glass transitions to mobility and isomerization in confined polymer systems aroused much interest. It was influenced by need for alignment in liquid crystalline flat panel displays, because in these displays films of polyimides are widely used. The surfaces are usually treated to produce uniform ali... | {
"Header 1": "*10.6.5 Liquid Crystalline Alignment*",
"token_count": 2035,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Here too, thermal polymerizations were conducted in solution within the ferroelectric liquid crystals, while exposing the reaction mixture to linearly polarized irradiation. The monomers can be shown as follows:
O O N N O O O N N CN O O O O O O O O N N O O O O O O O CN N N
Polymerization of these monomers was achie... | {
"Header 1": "*10.6.5 Liquid Crystalline Alignment*",
"token_count": 1933,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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It represents the number of generated carriers reaching the external circuit per unit time, compared with the number of photons absorbed at the same time [\[94\]](#page-794-0):
$$G = J_{\rm p}/eI_0(1-T)A$$
where *J*<sup>p</sup> is the photocurrent, *e* is the electric charge, *I*<sup>0</sup> is the number of incide... | {
"Header 1": "*10.6.5 Liquid Crystalline Alignment*",
"token_count": 1601,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Siloxanes with pendant carbazole groups were synthesized by Strohriegl [[254\]](#page-797-0) by the following technique:
$$\begin{array}{c|c} & & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & \\ & & ... | {
"Header 1": "*10.6.5 Liquid Crystalline Alignment*",
"token_count": 1229,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Similar work was done earlier by Natansohn [\[255](#page-797-0)], who copolymerized *N*-methyl, 1,3 hydroxymethyl carbazolyl acrylate with acryloyl-3<sup>0</sup> -hyroxypropyl-3,5-dinitrobenzoate:
$$O = O = O = O$$
$$O = O = O$$
$$O = O = O$$
$$O = O$$
$$O = O$$
$$O = O$$
$$O = O$$
$$O = O$$
$$O = O... | {
"Header 1": "*10.6.5 Liquid Crystalline Alignment*",
"token_count": 1998,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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The addition of electron donors, like dialkyl aniline, to Kapton polyimide film
N N O O O O O n
results in an enhancement of photocurrent by as much as five orders of magnitude, compared with the virgin material [[258\]](#page-797-0). Freulich explains the mechanism of enhancement as a result of radiation absorpt... | {
"Header 1": "*10.6.5 Liquid Crystalline Alignment*",
"token_count": 934,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Chan and coworkers [\[269](#page-798-0)] prepared polystyrenes and poly(methyl methacrylate)s that contain metal complex cores:
n O M n O
$$M = C$$
$$OC - Re - CI$$
$$OC - CO$$
or
$$M$$
= $\mathbb{R}^{H}$ $\mathbb{R}^{H}$ $\mathbb{R}^{H}$ $\mathbb{R}^{H}$ $\mathbb{R}^{H}$ $\mathbb{R}^{H}$ $\mat... | {
"Header 1": "*10.6.5 Liquid Crystalline Alignment*",
"token_count": 2017,
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This theory assumes that some fraction of absorbed photons produce bound thermalized electron-hole pairs that either recombine or dissociate under the combined effects of the Coulombic attraction and the electric field. The photo-generation efficiency is given as the product of the quantum yield of thermalized pair for... | {
"Header 1": "*10.6.5 Liquid Crystalline Alignment*",
"token_count": 2015,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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To achieve this goal, two research teams headed by Yu and by Yang tested a series of copolymers prepared by reacting a benzodithiophene derivative with various thienothiophenes. The aim was to lower the polymers' HMO by attaching successively stronger electron-withdrawing groups to the polymer backbone. The result wa... | {
"Header 1": "*10.6.5 Liquid Crystalline Alignment*",
"token_count": 2017,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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They observed a band gap of 2.3 and 2.2 eV for the block copolymer:
$$\mathsf{Br} = \mathsf{r} = \mathsf{r} = \mathsf{r} = \mathsf{r} = \mathsf{r} = \mathsf{r} = \mathsf{r} = \mathsf{r} = \mathsf{r} = \mathsf{r} = \mathsf{r} = \mathsf{r} = \mathsf{r} = \mathsf{r} = \mathsf{r} = \mathsf{r} = \mathsf{r} = \mathsf{r} = ... | {
"Header 1": "*10.6.5 Liquid Crystalline Alignment*",
"token_count": 2189,
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Through changing the acceptor groups, the electronic properties and energy levels of the copolymers were effectively tuned. Their results indicate that it is an effective approach to tuning the bandgaps in conjugated polymers. The polymers were used as donors in polymer solar cells. They reported, however, conversion e... | {
"Header 1": "*10.6.5 Liquid Crystalline Alignment*",
"token_count": 1695,
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1. How are the support materials utilized? Discuss
#### *Section 10.1.1.1*
- 1. Describe the Merrifield resin.
- 2. What are the two types of cross-linked polystyrenes that are used for support?
Review Questions 783
- 3. What is Tentagel? Describe and illustrate?
- 4. What is Jenda Gel? Explain and illustrate.
... | {
"Header 1": "*Section 10.1*",
"token_count": 517,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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- 1. Describe a planar heterojunction solar cell.
- 2. Describe a bulk heterojunction solar cell.
- 3. What is the equation that defines the efficiency of organic solar cells.
- 1. M.A. Kraus and A. Patchornik, *J. Polymer Sci., Macromol. Rev*.,15, 55 (1980)
- 2. M.A. Kraus and A. Patchornik, *Israel J. Chemistry*, 9... | {
"Header 1": "*Section 10.8*",
"token_count": 2025,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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*Tetrahedron,* 2005, *61,*12081
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- 34. Chinchill... | {
"Header 1": "*Section 10.8*",
"token_count": 1999,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
} |
Blumstein, and S.K. Tipathy, *Am. Chem. Soc. Polymer Preprints*, 1992, *33* (1), 576
- 68. S. Subramanyam and A. Blumstein, *Macromolecules,* 1991, *24*, 2668
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- 70. Y. Misumi and T. Masuda, *Macromolecules* 1998*, 31*, 7572
- 71. S. M. A. Karim, R. Nomura... | {
"Header 1": "*Section 10.8*",
"token_count": 1996,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Flory, *J. Am. Chem. Soc*., 1941, *63*, 3083, 3091,3096
- 108. P.J. Flory, "Principles of Polymer Chemistry," Cornell University Press, Ithaca, N.Y., 1953
- 109. W.H. Stockmayer, *J. Polym. Sci*., 1952, *9*, 69; *ibid*., 1953, *11*, 424
- 110. R.C. Dolby and R.H. Engebrecht, Canadian Pat. # 1,106,544 (1981) British Pat... | {
"Header 1": "*Section 10.8*",
"token_count": 2016,
"source_pdf": "datasets/websources/biochem/2012_Book_PrinciplesOfPolymerChemistry.pdf"
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Kobayashi, *J. Photopolym*. *Sci*. *Technol*. 1995,*8*, 257.
- 142. H. Tomita, K. Kudo, and K. Ichimura, *Liq*. *Cryst*. 1996, *20*, 171.
- 143. M. Schadt, K. Schmitt, V. Kozinkov, and V. Chigrinov, *Jpn.J. Appl*. *Phys*. 1992, *7*, 2155
- 144. K. Ichimura, Y. Akita, H. Akiyama, K. Kudo, and Y. Hayashi, *Macromolecules... | {
"Header 1": "*Section 10.8*",
"token_count": 2014,
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Maaref., and S.-S. Sun, *Am. Chem. Soc. Polymer Preprints*, 2003, *44*(1),86
- 181. J.C. Craneand R.J. Guglielmetti, *Organic Photochromic and Thermochromic Compounds*, Plenum Press, New York, 1999
- 182. S.E. Webber, *Chem. Rev*., 1990, *90*, 1469
- 183. R.B. Fox and R.F. Cozzens, *Macromolecules*, 1969, *2*, 181
- 18... | {
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"token_count": 1982,
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A* 1939, *171,* 398.
- 209. F. Agolini and F.P. Gay, *Macromolecules*, 1970, *3*, 249
- 210. C. Gilles, I. Faysal, and V. M. Rotello, *Macromolecules* 2000, *33*, 9173
- 211. Y. Nishikata, J. Minabe, K. Kono, and K. Baba, Kazuo Jpn. Kokai Tokkyo Koho JP 2000 109,719 (April 18, 2000)
- 212. A. Izumi, R. Nomura, and T. M... | {
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"token_count": 1969,
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Siesler, and S.Hvilsted, *Macromolecules*, 2003, *36*, 9373
- 243. R.G. Kepler, *Phys. Rev. Lett*., 1967, *18*, 951; P. Holtzman, R. Morris, R.C. Jarnagin, and M. Silver, *Phys. Rev. Lett*., 1967, *19*, 506
- 244. E.T. Kang, P. Ehrlich, A,P. Bhatt, and W.A. Anderson, Macromolecules, *17*, 1020 (1984)
- 245. F. Goodwin ... | {
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| A | of lactams, 290–296 |
|-------------------------------------------------------------|----------------------------------------------------------|
| ABA block copolymers, 305, 631 | of lactone... | {
"Header 1": "Index",
"token_count": 20099,
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} |
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*Garland Science*
Vice President: Denise Schanck Senior Editor: Michael Morales
Production Editor and Layout: Emma Jeffcock of EJ Publishing
Services
Illustrator: Nigel Orme
Developmental Editor: Monica Toledo
Editorial Assistants: Lamia Harik an... | {
"Header 1": "FOURTH EDITION ESSENTIAL CELL BIOLOGY",
"token_count": 1102,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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In our world there is no form of matter more astonishing than the living cell: tiny, fragile, marvelously intricate, continually made afresh, yet preserving in its DNA a record of information dating back more than three billion years, to a time when our planet had barely cooled from the hot materials of the nascent sol... | {
"Header 1": "Preface",
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The authors acknowledge the many contributions of professors and students from around the world in the creation of this fourth edition. In particular, we are grateful to the students who participated in our focus groups; they provided invaluable feedback about their experiences using the book and our multimedia, and ma... | {
"Header 1": "Acknowledgments",
"token_count": 902,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
} |
| Chapter 1 Cells: The Fundamental Units of Life | 1 |
|--------------------------------------------------------------------|---------|
| Panel 1–1 Microscopy | 10–11 |
| Panel 1–2 Cell Architecture | 25 ... | {
"Header 1": "Contents and Special Features",
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| Chapter 1<br>Cells: The Fundamental Units of Life | 1 | Comparing Genome Sequences Reveals Life's<br>Common Heritage | 33 |
|----------------------------------------------------------------------------------|----|---------------------... | {
"Header 1": "Detailed Contents",
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coli | 27 | Noncovalent Bonds Specify the Precise Shape | |
| Brewer's Yeast Is a Simple Eukaryotic Cell | 27 | of a Macromolecule ... | {
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What does it mean to be living? Petunias, people, and pond scum are all alive; stones, sand, and summer breezes are not. But what are the fundamental properties that characterize living things and distinguish them from nonliving matter?
The answer begins with a basic fact that is taken for granted now, but marked a r... | {
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Let us begin with size. A bacterial cell—say a Lactobacillus in a piece of cheese—is a few **micrometers**, or µm, in length. That's about 25 times smaller than the width of a human hair. A frog egg—which is also a single cell—has a diameter of about 1 millimeter. If we scaled them up to make the Lactobacillus the size... | {
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"Header 3": "Cells Vary Enormously in Appearance and Function",
"token_count": 888,
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Despite the extraordinary diversity of plants and animals, people have recognized from time immemorial that these organisms have something in common, something that entitles them all to be called living things. But while it seemed easy enough to recognize life, it was remarkably difficult to say in what sense all livin... | {
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"Header 3": "Living Cells All Have a Similar Basic Chemistry",
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A cell reproduces by replicating its DNA and then dividing in two, passing a copy of the genetic instructions encoded in its DNA to each of its daughter cells. That is why daughter cells resemble the parent cell. However, the copying is not always perfect, and the instructions are occasionally corrupted by *mutations* ... | {
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A cell's genome—that is, the entire sequence of nucleotides in an organism's DNA—provides a genetic program that instructs the cell how to behave. For the cells of plant and animal embryos, the genome directs the growth and development of an adult organism with hundreds of different cell types. Within an individual pla... | {
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"Header 3": "Genes Provide the Instructions for Cell Form, Function, and Complex Behavior",
"token_count": 317,
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Today, we have the technology to decipher the underlying principles that govern the structure and activity of the cell. But cell biology started without these tools. The earliest cell biologists began by simply looking at tissues and cells, and later breaking them open or slicing them up, attempting to view their conte... | {
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"Header 3": "Cells Under the Microscope",
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The development of the light microscope depended on advances in the production of glass lenses. By the seventeenth century, lenses were powerful enough to make out details invisible to the naked eye. Using an instrument equipped with such a lens, Robert Hooke examined a piece of cork and in 1665 reported to the Royal S... | {
"Header 1": "Cells: The Fundamental Units of Life",
"Header 3": "The Invention of the Light Microscope Led to the Discovery of Cells",
"token_count": 719,
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If you cut a very thin slice from a suitable plant or animal tissue and view it using a light microscope, you will see that the tissue is divided into thousands of small cells. These may be either closely packed or separated from one another by an *extracellular matrix*, a dense material often made of protein fibers em... | {
"Header 1": "Cells: The Fundamental Units of Life",
"Header 3": "Light Microscopes Allow Examination of Cells and Some of Their Components",
"token_count": 238,
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You have embarked on an ambitious research project: to create life in a test tube. You boil up a rich mixture of yeast extract and amino acids in a flask along with a sprinkling of the inorganic salts known to be essential for life. You seal the flask and allow it to cool. After several months, the liquid is as clear a... | {
"Header 1": "Cells: The Fundamental Units of Life",
"Header 3": "Question 1–3",
"token_count": 900,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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For the highest magnification and best resolution, one must turn to an electron microscope, which can reveal details down to a few nanometers. Cell samples for the electron microscope require painstaking preparation. Even for light microscopy, a tissue often has to be *fixed* (that is, preserved by pickling in a reacti... | {
"Header 1": "Cells: The Fundamental Units of Life",
"Header 3": "The Fine Structure of a Cell Is Revealed by Electron Microscopy",
"token_count": 891,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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Dividing nuclei in a fly embryo seen with a fluorescence microscope after staining with specific fluorescent dyes.
Fluorescent dyes absorb light at one wavelength and emit it at another, longer wavelength. Some such dyes bind specifically to particular molecules in cells and can reveal... | {
"Header 1": "(A)",
"Header 3": "FLUORESCENT PROBES",
"token_count": 1663,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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A bacterium weighs about 10–12 g and can divide every 20 minutes. If a single bacterial cell carried on dividing at this rate, how long would it take before the mass of bacteria would equal that of the Earth (6 × 1024 kg)? Contrast your result with the fact that bacteria originated at least 3.5 billion years ago and ha... | {
"Header 1": "(A)",
"Header 3": "Question 1–4",
"token_count": 848,
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Traditionally, all prokaryotes have been classified together in one large group. But molecular studies reveal that there is a gulf within the class of prokaryotes, dividing it into two distinct *domains* called the bacteria and the archaea. Remarkably, at a molecular level, the members of these two domains differ as mu... | {
"Header 1": "(A)",
"Header 3": "The World of Prokaryotes Is Divided into Two Domains: Bacteria and Archaea",
"token_count": 221,
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The nucleus is usually the most prominent organelle in a eukaryotic cell (Figure 1–14). It is enclosed within two concentric membranes that form the *nuclear envelope*, and it contains molecules of DNA—extremely long polymers that encode the genetic information of the organism. In the light microscope, these giant DNA ... | {
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"Header 3": "The Nucleus Is the Information Store of the Cell",
"token_count": 419,
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Mitochondria are present in essentially all eukaryotic cells, and they are among the most conspicuous organelles in the cytoplasm (see Figure 1–7B). In a fluorescence microscope, they appear as worm-shaped structures that often form branching networks (Figure 1–16). When seen with an electron microscope, individual mit... | {
"Header 1": "(A)",
"Header 3": "Mitochondria Generate Usable Energy from Food to Power the Cell",
"token_count": 924,
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Chloroplasts are large, green organelles that are found only in the cells of plants and algae, not in the cells of animals or fungi. These organelles have an even more complex structure than mitochondria: in addition to their two surrounding membranes, they possess internal stacks of membranes containing the green pigm... | {
"Header 1": "(A)",
"Header 3": "Chloroplasts Capture Energy from Sunlight",
"token_count": 457,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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Nuclei, mitochondria, and chloroplasts are not the only membraneenclosed organelles inside eukaryotic cells. The cytoplasm contains a profusion of other organelles that are surrounded by single membranes (see Figure 1–7A). Most of these structures are involved with the cell's ability to import raw materials and to expo... | {
"Header 1": "Internal Membranes Create Intracellular Compartments with Different Functions",
"token_count": 1074,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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If we were to strip the plasma membrane from a eukaryotic cell and then remove all of its membrane-enclosed organelles, including the nucleus, endoplasmic reticulum, Golgi apparatus, mitochondria, chloroplasts, and so on, we would be left with the cytosol (see Figure 1–23B). In other words, the cytosol is the part of t... | {
"Header 1": "Internal Membranes Create Intracellular Compartments with Different Functions",
"Header 3": "The Cytosol Is a Concentrated Aqueous Gel of Large and Small Molecules",
"token_count": 202,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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The cytoplasm is not just a structureless soup of chemicals and organelles. Using an electron microscope, one can see that in eukaryotic cells the cytosol is criss-crossed by long, fine filaments. Frequently, the filaments are seen to be anchored at one end to the plasma membrane or to radiate out from a central site a... | {
"Header 1": "Internal Membranes Create Intracellular Compartments with Different Functions",
"Header 3": "The Cytoskeleton Is Responsible for Directed Cell Movements",
"token_count": 444,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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Suggest a reason why it would be advantageous for eukaryotic cells to evolve elaborate internal membrane systems that allow them to import substances from the outside, as shown in Figure 1–24.
directions and distribute them equally to the two daughter cells (**Figure 1–27**). Intermediate in thickness between actin f... | {
"Header 1": "QUESTION 1–5",
"token_count": 383,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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The cell interior is in constant motion. The cytoskeleton is a dynamic jungle of protein ropes that are continually being strung together and taken apart; its filaments can assemble and then disappear in a matter of minutes. *Motor proteins* use the energy stored in molecules of ATP to trundle along these tracks and ca... | {
"Header 1": "QUESTION 1–5",
"Header 3": "The Cytoplasm Is Far from Static",
"token_count": 364,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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Eukaryotic cells are typically 10 times the length and 1000 times the volume of prokaryotic cells, although there is huge size variation within each category. They also possess a whole collection of features—a cytoskeleton, mitochondria, and other organelles—that set them apart from bacteria and archaea.
When and how... | {
"Header 1": "QUESTION 1–5",
"Header 3": "Eukaryotic Cells May Have Originated as Predators",
"token_count": 1788,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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All cells are thought to be descended from a common ancestor, whose fundamental properties have been conserved through evolution. Thus knowledge gained from the study of one organism contributes to our understanding of others, including ourselves. But certain organisms are easier than others to study in the laboratory.... | {
"Header 1": "QUESTION 1–5",
"Header 3": "Model Organisms",
"token_count": 390,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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We tend to be preoccupied with eukaryotes because we are eukaryotes ourselves. But human cells are complicated and reproduce relatively slowly. To get a handle on the fundamental biology of eukaryotic cells, it is often advantageous to study a simpler cell that reproduces more rapidly. A popular choice has been the bud... | {
"Header 1": "QUESTION 1–5",
"Header 3": "Brewer's Yeast Is a Simple Eukaryotic Cell",
"token_count": 464,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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The large multicellular organisms that we see around us—both plants and animals—seem fantastically varied, but they are much closer to one another in their evolutionary origins, and more similar in their basic cell biology, than the great host of microscopic single-celled organisms. Whereas bacteria, archaea, and eukar... | {
"Header 1": "QUESTION 1–5",
"Header 3": "*Arabidopsis* Has Been Chosen as a Model Plant",
"token_count": 275,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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Multicellular animals account for the majority of all named species of living organisms, and the majority of animal species are insects. It is fitting, therefore, that an insect, the small fruit fly *Drosophila melanogaster* (Figure 1–33), should occupy a central place in biological research. In fact, the foundations o... | {
"Header 1": "QUESTION 1–5",
"Header 3": "Model Animals Include Flies, Fish, Worms, and Mice",
"token_count": 854,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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All living things are made of cells, and all cells—as we have discussed in this chapter—are fundamentally similar inside: they store their genetic instructions in DNA molecules, which direct the production of RNA molecules, which in turn direct the production of proteins. It is largely the proteins that carry out the c... | {
"Header 1": "QUESTION 1–5",
"Header 3": "life's common mechanisms",
"token_count": 207,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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All cells come from other cells, and the only way to make a new cell is through division of a preexisting one. To reproduce, a parent cell must execute an orderly sequence of reactions, through which it duplicates its contents and divides in two. This critical process of duplication and division—known as the *cell-divi... | {
"Header 1": "QUESTION 1–5",
"Header 3": "Division and discovery",
"token_count": 522,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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*Saccharomyces cerevisiae* is another kind of yeast and is one of a handful of model organisms biologists have chosen to study to expand their understanding of how cells work. Also used to brew beer, *S. cerevisiae* divides by forming a small bud that grows steadily until it separates from the mother cell (see Figures ... | {
"Header 1": "QUESTION 1–5",
"Header 3": "Next of kin",
"token_count": 1463,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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Humans are not mice—or fish or flies or worms or yeast—and so we also study human beings themselves. Like bacteria or yeast, our individual cells can be harvested and grown in culture, where we can study their biology and more closely examine the genes that govern their functions. Given the appropriate surroundings, mo... | {
"Header 1": "QUESTION 1–5",
"Header 3": "Biologists Also Directly Study Human Beings and Their Cells",
"token_count": 634,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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At a molecular level, evolutionary change has been remarkably slow. We can see in present-day organisms many features that have been preserved through more than 3 billion years of life on Earth—about one-fifth of the age of the universe. This evolutionary conservatism provides the foundation on which the study of molec... | {
"Header 1": "QUESTION 1–5",
"Header 3": "Comparing Genome Sequences Reveals Life's Common Heritage",
"token_count": 1575,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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Although our view of genome sequences tends to be "gene-centric," our genomes contain much more than just genes. The vast bulk of our DNA does not code for proteins or for functional RNA molecules. Instead, it includes a mixture of sequences that help regulate gene activity, plus sequences that seem to be dispensable. ... | {
"Header 1": "QUESTION 1–5",
"Header 3": "Genomes Contain More Than Just Genes",
"token_count": 236,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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- • Cells are the fundamental units of life. All present-day cells are believed to have evolved from an ancestral cell that existed more than 3 billion years ago.
- • All cells are enclosed by a plasma membrane, which separates the inside of the cell from its environment.
- • All cells contain DNA as a store of genetic... | {
"Header 1": "QUESTION 1–5",
"Header 3": "Essential Concepts",
"token_count": 804,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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#### Question 1–8
By now you should be familiar with the following cellular components. Briefly define what they are and what function they provide for cells.
- A. cytosol
- B. cytoplasm
- C. mitochondria
- D. nucleus
- E. chloroplasts
- F. lysosomes
- G. chromosomes
- H. Golgi apparatus
- I. peroxisomes
- J. plasm... | {
"Header 1": "QUESTION 1–5",
"Header 3": "Questions",
"token_count": 868,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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Apply the principle of exponential growth of a culture as described in Question 1–13 to the cells in a multicellular organism, such as yourself. There are about 1013 cells in your body. Assume that one cell acquires a mutation that allows it to divide in an uncontrolled manner (i.e., it becomes a cancer cell). Some can... | {
"Header 1": "QUESTION 1–5",
"Header 3": "Question 1–15",
"token_count": 602,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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It is at first sight difficult to accept that living creatures are merely chemical systems. Their incredible diversity of form, their seemingly purposeful behavior, and their ability to grow and reproduce all seem to set them apart from the world of solids, liquids, and gases that chemistry normally describes. Indeed, ... | {
"Header 1": "Chemical Components of Cells",
"token_count": 740,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
} |
Each atom has at its center a dense, positively charged nucleus, which is surrounded at some distance by a cloud of negatively charged electrons, held there by electrostatic attraction to the nucleus (Figure 2–1). The nucleus consists of two kinds of subatomic particles: **protons**, which are positively charged, and n... | {
"Header 1": "Chemical Components of Cells",
"Header 3": "Cells Are Made of Relatively Few Types of Atoms",
"token_count": 944,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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To understand how atoms come together to form the molecules that make up living organisms, we have to pay special attention to the atoms' electrons. Protons and neutrons are welded tightly to one another in an atom's nucleus, and they change partners only under extreme conditions—during radioactive decay, for example, ... | {
"Header 1": "Chemical Components of Cells",
"Header 3": "The Outermost Electrons Determine How Atoms Interact",
"token_count": 2047,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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The two cases shown represent extremes; often, covalent bonds form with a partial transfer (unequal sharing of electrons), resulting in a polar covalent bond, as we discuss shortly.
Figure 2-7 The chemistry of life is predominantly the chemistry of lighter **elements.** When ordered by their atomic number into a peri... | {
"Header 1": "Chemical Components of Cells",
"Header 3": "The Outermost Electrons Determine How Atoms Interact",
"token_count": 308,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
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All of the characteristics of a cell depend on the molecules it contains. A **molecule** is a cluster of atoms held together by **covalent bonds**, in which electrons are shared rather than transferred between atoms. The shared electrons complete the outer shells of the interacting atoms. In the simplest possible molec... | {
"Header 1": "Chemical Components of Cells",
"Header 3": "Covalent Bonds Form by the Sharing of Electrons",
"token_count": 637,
"source_pdf": "datasets/websources/biochem/Alberts_-_Essential_Cell_Biology__4th_ed._.pdf"
} |
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