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- https://bio.libretexts.org/Bookshelves/Cell_and_Molecular_Biology/Book%3A_Biofundamentals_(Klymkowsky_and_Cooper)/03%3A_Evolutionary_mechanisms_and_the_diversity_of_life/3.13%3A_A_short_note_on_pedagogical_weirdnessWhat is important to remember however is that this conclusion is based on five totally unrealistic assumptions, namely that: 1) the population is essentially infinite, so we did not have to consider p...What is important to remember however is that this conclusion is based on five totally unrealistic assumptions, namely that: 1) the population is essentially infinite, so we did not have to consider processes like genetic drift (discussed below); 2) the population is isolated, no individuals leave and none enter; 3) mutations do not occur; 4) mating between individuals is completely random (discussed further in Chapter 4); and 5) there are no differential reproductive effects, that is, no natur…
- https://bio.libretexts.org/Bookshelves/Cell_and_Molecular_Biology/Book%3A_Biofundamentals_(Klymkowsky_and_Cooper)/01%3A_Understanding_science_and_thinking_scientifically/1.4%3A_Teaching_and_Learning_ScienceWhile it is now accepted that the Earth rotates around its axis and revolves around the sun, which is itself moving around the center of the Milky Way galaxy, and that the Universe as a whole is expan...While it is now accepted that the Earth rotates around its axis and revolves around the sun, which is itself moving around the center of the Milky Way galaxy, and that the Universe as a whole is expanding at what appears to be an ever increasing rate, none of these facts are immediately obvious and relatively few people who believe or accept them would be able to explain how we have come to know that these ideas accurately reflect the way the universe is organized.
- https://bio.libretexts.org/Bookshelves/Cell_and_Molecular_Biology/Book%3A_Biofundamentals_(Klymkowsky_and_Cooper)/02%3A_Lifes_diversity_and_origins/2.05%3A_The_Death_of_VitalismPlease do not memorize the reaction, what is of importance here is to recognize that this is just another chemical reaction, not exactly what the reaction is. Based on this and similar observations on...Please do not memorize the reaction, what is of importance here is to recognize that this is just another chemical reaction, not exactly what the reaction is. Based on this and similar observations on the in vitro synthesis of other, more complex organic compounds, we (that is, scientists) are now comfortable with the idea that all molecules found within cells can, in theory at least, be synthesized outside of cells, using appropriate procedures.
- https://bio.libretexts.org/Courses/Coastline_College/Book-_Cells_-_Molecules_and_Mechanisms_(Wong)/04%3A_Molecular_Interactions_Thermodynamics_and_Reaction_CouplingWhile the diversity of organisms and the unique properties of each individual organism are the products of evolutionary processes, initiated billions of years ago, it is equally important to recognize...While the diversity of organisms and the unique properties of each individual organism are the products of evolutionary processes, initiated billions of years ago, it is equally important to recognize that all biological systems and processes, from growth and cell division to thoughts and feelings, obey the rules of chemistry and physics, and in particular the laws of thermodynamics. Klymkowsky (University of Colorado Boulder) and Melanie M.
- https://bio.libretexts.org/Courses/Coastline_College/Book-_Cells_-_Molecules_and_Mechanisms_(Wong)/04%3A_Molecular_Interactions_Thermodynamics_and_Reaction_Coupling/4.10%3A_The_implications_of_bond_polarityAs the water strider walks on the surface of the water, the molecules of its feet do not form H-bond-type electrostatic interactions with water molecules, they are said to be hydrophobic, although tha...As the water strider walks on the surface of the water, the molecules of its feet do not form H-bond-type electrostatic interactions with water molecules, they are said to be hydrophobic, although that is clearly a bad name - they are not afraid of water, rather they are simply apathetic to it.
- https://bio.libretexts.org/Courses/Coastline_College/Book-_Cells_-_Molecules_and_Mechanisms_(Wong)/04%3A_Molecular_Interactions_Thermodynamics_and_Reaction_Coupling/4.03%3A_Thinking_entropically_(and_thermodynamically)Assuming that you have been introduced to chemistry, you might recognize the Gibb’s free energy equation: ΔG = ΔH - TΔS, where T is the temperature of the system 150 . From our particularly biological...Assuming that you have been introduced to chemistry, you might recognize the Gibb’s free energy equation: ΔG = ΔH - TΔS, where T is the temperature of the system 150 . From our particularly biological perspective, we can think of ΔH as the amount of heat released into (or absorbed from) the environment in the course of a reaction, and ΔS as the change in a system factor known as entropy.
- https://bio.libretexts.org/Bookshelves/Cell_and_Molecular_Biology/Book%3A_Biofundamentals_(Klymkowsky_and_Cooper)/03%3A_Evolutionary_mechanisms_and_the_diversity_of_life/3.22%3A_Sympatric_speciationWhile the logic and mechanisms of allopatric speciation are relatively easy to grasp (we hope), there is a second type of speciation, known as sympatric speciation, which was originally more controver...While the logic and mechanisms of allopatric speciation are relatively easy to grasp (we hope), there is a second type of speciation, known as sympatric speciation, which was originally more controversial. Through a process of disruptive selection (see above), organisms that live primarily on a particular plant (or part of a plant) can be subject to different selective pressures, and reproductive isolation will enable the populations to more rapidly adapt.
- https://bio.libretexts.org/Bookshelves/Cell_and_Molecular_Biology/Book%3A_Biofundamentals_(Klymkowsky_and_Cooper)/03%3A_Evolutionary_mechanisms_and_the_diversity_of_life/3.02%3A_Natural_and_un-natural_groupsWe have placed each of the other types of bear-like organisms, the spectacled bear (Tremarctos ornatus), the sloth bear (Melurus ursinus), the sun bear (Helarctos mayalanus), and the giant panda (Ailu...We have placed each of the other types of bear-like organisms, the spectacled bear (Tremarctos ornatus), the sloth bear (Melurus ursinus), the sun bear (Helarctos mayalanus), and the giant panda (Ailuropoda melanoleuca) in their own separate genus, because scientists consider these species more different from one another than are the members of the genus Ursus.
- https://bio.libretexts.org/Courses/Coastline_College/Book-_Cells_-_Molecules_and_Mechanisms_(Wong)/04%3A_Molecular_Interactions_Thermodynamics_and_Reaction_Coupling/4.04%3A_Reaction_ratesKnowing whether a reaction is thermodynamically favorable and its equilibrium constant does not tell us much (or really anything) about whether the reaction actually occurs to any significant extent u...Knowing whether a reaction is thermodynamically favorable and its equilibrium constant does not tell us much (or really anything) about whether the reaction actually occurs to any significant extent under the conditions with which we are concerned. For example, consider a wooden log, which is composed mainly of the carbohydrate polymer cellulose (CH 2 O) n . In the presence of molecular oxygen (O 2 ) the reaction:
- https://bio.libretexts.org/Courses/Coastline_College/Book-_Cells_-_Molecules_and_Mechanisms_(Wong)/04%3A_Molecular_Interactions_Thermodynamics_and_Reaction_Coupling/4.08%3A_Bond_Stability_and_Thermal_Motion_(a_non-biological_moment)If, for example, the expression of a gene depends upon a protein binding (reversibly) to specific sites on a DNA molecule, and if there are relatively small numbers of that protein and (usually) only ...If, for example, the expression of a gene depends upon a protein binding (reversibly) to specific sites on a DNA molecule, and if there are relatively small numbers of that protein and (usually) only one or two copies of the gene (that is, the DNA molecule) present, we will find that whether or not a copy of the protein is bound to a specific region of the DNA is a stochastic process 161 . If there are enough cells, then the group average will be predictable, but the behavior of any one cell wi…
- https://bio.libretexts.org/Courses/Coastline_College/Book-_Cells_-_Molecules_and_Mechanisms_(Wong)/01%3A_Understanding_Science_and_Thinking_Scientifically/1.02%3A_Models_Hypotheses_and_TheoriesIf there are multiple “theories” to explain a particular phenomenon, it is more correct to say that i) these are not actually theories, in the scientific sense, but rather working models or simple spe...If there are multiple “theories” to explain a particular phenomenon, it is more correct to say that i) these are not actually theories, in the scientific sense, but rather working models or simple speculations, and that ii) one or more, and perhaps all of these models are incorrect or incomplete.