then it's just bbq chicken from there 🎥 crash course ochem sn1 and sn2 "When considering whether a nucleophilic substitution is likely to occur via an SN1 or SN2 mechanism, we really need to consider three factors: 1) The electrophile: when the leaving group is attached to a methyl group or a primary carbon, an SN2 mechanism is favored (here the electrophile is unhindered by surrounded groups, and any carbocation intermediate would be high-energy and thus unlikely). When the leaving group is attached to a tertiary, allylic, or benzylic carbon, a carbocation intermediate will be relatively stable and thus an SN1 mechanism is favored. These patterns of reactivity of summarized below. 2) The nucleophile: powerful nucleophiles, especially those with negative charges, favor the SN2 mechanism. Weaker nucleophiles such as water or alcohols favor the SN1 mechanism. 3) The solvent: Polar aprotic solvents favor the SN2 mechanism by enhancing the reactivity of the nucleophile. Polar protic solvents favor the SN1 mechanism by stabilizing the transition state and carbocation intermediate. SN1 reactions are called solvolysis reactions when the solvent is the nucleophile." #ochem #organicchem #chemistry #chemistrymajor #biologymajor

and probably has a reaction lined up after evolution at their common ancestor's firm 🎥 crash course biology cellular respiration "Pyruvate dehydrogenase (PDH) is one of the two component enzymes of a huge pyruvate dehydrogenase complex, which is located in mitochondria to catalyze conversion of pyruvate to acetyl-CoA, the entry substrate for the TCA cycle [102]. PDH performs a decarboxylation of pyruvate and a reductive acetylation of lipoate, which is covalently bound to the second enzyme component. PDH is regulated by pyruvate dehydrogenase kinase (PDK), which phosphorylates PDH, and phosphorylated PDH is not active. Because the activity of PDH is critical for the oxidative phosphorylation of glucose, it has been a general assumption that PDH activity is compromised, but PDK is active, in cancer cells in which the majority of pyruvate has to be converted to lactate. This notion creates a paradoxical situation in which PDH inhibition is a valid strategy for cancer therapy." #biochem #biology #cellbiology #metabolism

other halides got patched 🎥 crash course ochem alkenes and electrophilic addition "One of the most important reactions for alkenes is called electrophilic addition. In this chapter several variations of the electrophilic addition reaction will be discussed. Each case will have aspects common among all electrophilic addition. In this section, the electrophilic addition reaction will be discussed in general to provide a better understanding of subsequent alkene reactions. As discussed in Section 6-5, the double bond in alkenes is electron rich due to the prescience of 4 electrons instead of the two in a single bond. Also, the pi electrons are positioned above and below the double bond making them more accessibly for reactions. Overall, double bonds can easily donate lone pair electrons to act like a nucleophile (nucleus-loving, electron rich, a Lewis acid). During an electrophilic addition reactions, double bonds donate lone pair electrons to an electrophile (Electron-loving, electron poor, a Lewis base). There are many types of electrophilic addition, but this section will focus on the addition of hydrogen halides (HX). Many of the basic ideas discussed will aplicable to subsequent electrophilic addition reactions. General Reaction Overall during this reaction the pi bond of the alkene is broken to form two single, sigma bonds. As shown in the reaction mechanism, one of these sigma bonds is connected to the H and the other to the X of the hydrogen halide. This reaction works well with HBr and HCl. HI can also but used but is is usually generated during the reaction by reacting potassium iodidie (KI) with phosphoric acid (H3PO4)." #ochem #organicchemistry #chemistry

are you a monosaccharide? ive never meant anyone as sweet as you😣 footage from hybrid biomedical "Paleoproteomics, the study of ancient proteins, is a rapidly growing field at the intersection of molecular biology, paleontology, archaeology, paleoecology, and history. Paleoproteomics research leverages the longevity and diversity of proteins to explore fundamental questions about the past. While its origins predate the characterization of DNA, it was only with the advent of soft ionization mass spectrometry that the study of ancient proteins became truly feasible. Technological gains have allowed increasing opportunities to better understand preservation, degradation, and recovery of the rich bioarchive of ancient proteins found in the archaeological and paleontological records. Growing from a handful of studies in the 1990s on individual abundant ancient proteins, paleoproteomics today is an expanding field with diverse applications ranging from the taxonomic identification of highly fragmented bones and shells and the phylogenetic resolution of extinct species to the exploration of past cuisines from dental calculus and pottery food crusts and the characterization of past diseases. More broadly, these studies have opened new doors in understanding past human–animal interactions, the reconstruction of past environments and environmental changes, the expansion of the hominin fossil record through large scale screening of nondiagnostic bone fragments, and the phylogenetic resolution of the vertebrate fossil record. Even with these advances, much of the ancient proteomic record still remains unexplored. Here we provide an overview of the history of the field, a summary of the major methods and applications currently in use, and a critical evaluation of current challenges. We conclude by looking to the future, for which innovative solutions and emerging technology will play an important role in enabling us to access the still unexplored “dark” proteome, allowing for a fuller understanding of the role ancient proteins can play in the interpretation of the past. Although proteins decay, nitrogen recycling is not completely efficient, and in protected environments (e.g., bones, teeth, eggshell) proteins can persist for millions of years or more. Protein fragments are recognizable in fossils (e.g., seeds, b0ne), worked biological remains, (e.g., wood, textiles, archaeological and art historical artifacts), as residues on cooking vessels, and also entrapped within soils and sediments. There is more protein nitrogen in this “d34d pool” than there is in all the living cells on earth. Encoded by DNA, proteins pack the same amount of sequence information into approximately one-sixth the number of atoms. For example, a 50 bp fragment of DNA (30.4 kDa) has a larger mass than many intact proteins, including β-lactoglobulin (18.4 kDa), hemoglobin (15.9 kDa), and amelogenin (24.1 kDa). Protein folding and aggregation further protect proteins from chemical attack and facilitate entrapment. With fewer atoms, fewer chemical bonds, and a more compact structure, proteins consequently fall apart more slowly than DNA. However, the greater range of reactive species and our limited ability to recover direct information about their state of decay mean that ancient proteins stretch the limits of our understanding of decay processes and diagenetic modification. Yet the results are hardly esoteric, as modifications associated with ancient proteins have relevance for understanding aging and diseased tissues, and are induced during the production and consumption of protein-containing materials and foods." #biology #guthealth #gutmicrobiome

and then all the ideal gas molecules descended from the skies to carry you away. CW: emotional "Many chemists had dreamed of having an equation that describes relation of a gas molecule to its environment such as pressure or temperature. However, they had encountered many difficulties because of the fact that there always are other affecting factors such as intermolecular forces. Despite this fact, chemists came up with a simple gas equation to study gas behavior while putting a blind eye to minor factors. When dealing with gas, a famous equation was used to relate all of the factors needed in order to solve a gas problem. This equation is known as the Ideal Gas Equation. As we have always known, anything ideal does not exist. In this issue, two well-known assumptions should have been made beforehand: the particles have no forces acting among them, and these particles do not take up any space, meaning their atomic volume is completely ignored. An ideal gas is a hypothetical gas dreamed by chemists and students because it would be much easier if things like intermolecular forces do not exist to complicate the simple Ideal Gas Law. Ideal gases are essentially point masses moving in constant, random, straight-line motion. Its behavior is described by the assumptions listed in the Kinetic-Molecular Theory of Gases. This definition of an ideal gas contrasts with the Non-Ideal Gas definition, because this equation represents how gas actually behaves in reality. For now, let us focus on the Ideal Gas." #genchem #chemistry #chemtok #gaslaw

key "Tungsten is the heaviest known engineering metal with an astounding density of 19.35 g/cm3. It is a bright white metal in its purest state. However, the presence of carbon and oxygen traces causes it to break easily under shock loading. Tungsten is notable for its remarkable tensile strength and resilience to high temperatures.  Tungsten carbide's abrasiveness and tolerance to high temperatures make it an excellent choice for a variety of applications, including cutting and drilling tools. Furthermore, tungsten is an essential component in many industrial fields due to its exceptional electrical and thermal conductivity. This article explores the essential contributions of tungsten as we delve into its composition, applications, and unique qualities.  What Is Tungsten? Tungsten is a chemical element with the atomic number 74 and the symbol W. It is a transition metal with a strong atomic structure on the periodic table. Its tensile strength and high melting point (3,422 °C) are two of its most notable characteristics. These attributes help explain why tungsten is so important to so many different industrial uses. Is Tungsten the Same as Wolfram? Yes, tungsten and wolfram refer to the same chemical element. The terms are used interchangeably, with "tungsten" more common in modern usage and "wolfram" originating from its earlier discovery and historical nomenclature. What Is the Origin of Tungsten? Spanish mineralogists Juan and Fausto Elhuyar discovered tungsten in 1783. An important development in the history of the element was the isolation of tungsten oxide and its subsequent reduction to tungsten metal by heating it with carbon as a result of their research at the Seminary at Vergara. What Is Tungsten Made Of? Tungsten is not naturally found in its pure form but is primarily present in minerals such as wolframite and scheelite. Wolframite is a solid solution of ferberite and hübnerite, composed of iron–manganese tungstate (Fe,Mn)WO4. Scheelite, another tungsten-bearing mineral, is identified as calcium tungstate (CaWO4). " #genchem #chemistry

are you made of RNA? because uracil-ly goose😝 "Transcription initiation is the phase during which the first nucleotides in the RNA chain are synthesized. It is a multistep process that starts when the RNAP holoenzyme binds to the DNA template and ends when the core polymerase escapes from the promoter after the synthesis of approximately the first nine nucleotides. The stages of the transcription initiation process, which are summarized in Figure 2, can be described in terms of the types of interaction between the RNAP and the nucleic acids that are involved. The first stage in transcription initiation is the formation of a complex between the holoenzyme and the DNA sequence at the promoter, which is in the form of a double-stranded DNA. This complex is termed a closed binary complex or closed complex. The second stage is the unwinding of a short region of DNA within the sequence that is bound to the RNAP. The complex between the polymerase and the partially melted DNA is termed an open binary complex or open complex. The conversion of the closed complex into the open complex leads to the establishment of tight binding between the RNAP and the promoter sequence. For strong promoters, the conversion into an open complex is irreversible. The third stage is the incorporation of two ribonucleotides and the formation of a phosphodiester bond between them. Because the complex at that stage contains an RNA as well as DNA, it is called an initiation ternary complex. Up to seven additional ribonucleotides can be added to the RNA chain without any movement of the polymerase. After the addition of each base, there is a certain probability that the enzyme will release the short (up to nine bases long) RNA chain." #molecularbiology #biology #biotok #transcription #rna #dna

good luck, future fives #apbiology #apbio #biology #biologytok

good luck to all the future fives in the chat🎥nanobot 2024 showreel ""The AP® Biology exam is hard when compared to a typical high school-level biology course exam. The AP® course exams are designed to measure a higher level of content understanding and require you to analyze and apply that knowledge; all of this is typically taught at the college level. If you compare the AP® Biology exam to other AP® exams, the AP® Biology exam is slightly easier to pass than other AP® course exams for the following reasons. In 2023, about 64.4% of the 239,470 students who took the AP® Biology exam scored a 3 or higher. The 2023 AP® Biology exam yielded a mean score of 3.04. Test-takers in the top ~30% typically received a 4 of 5 on this exam, with 10-15% receiving the maximum score of 5. When viewed in comparison to the other exams in the AP® Sciences category, the AP® Biology exam is about average in terms of passing rate. Three of the seven exams in the group had a pass rate higher in 2021 than the AP® Biology exam, and three had a lower passing rate. Our AP® Biology score calculator clearly shows that you would need to answer 50% of the multiple choice questions right and get at least half of the points for each free response question to achieve a score of 3 or better on this exam. Many students feel that taking the AP® Biology exam is worth it. Primarily, AP® courses help students understand the increased difficulty and faster pace that is required in college courses. Doing well in an AP® course can also help build your academic confidence. The 2024 AP® Biology exam will take place on Thursday, May 16, 2024, at 12pm Local Time." #biology #apbiology #biologytok #immunology #microbiology #cellbiology

What other IMFs exist? How do they help explain the boiling points of various compounds? "For a hydrogen bond to occur there must be both a hydrogen donor and an acceptor present. The donor in a hydrogen bond is the atom to which the hydrogen atom participating in the hydrogen bond is covalently bonded, and is usually a strongly electronegative atom such as N, O, or F. The hydrogen acceptor is the neighboring electronegative ion or molecule, and must posses a lone electron pair in order to form a hydrogen bond. Since the hydrogen donor is strongly electronegative, it pulls the covalently bonded electron pair closer to its nucleus, and away from the hydrogen atom. The hydrogen atom is then left with a partial positive charge, creating a dipole-dipole attraction between the hydrogen atom bonded to the donor, and the lone electron pair on the acceptor. Hydrogen bonds can occur within one single molecule, between two like molecules, or between two unlike molecules. Intramolecular hydrogen bonds: Intramolecular hydrogen bonds are those which occur within one single molecule. This occurs when two functional groups of a molecule can form hydrogen bonds with each other. In order for this to happen, both a hydrogen donor an acceptor must be present within one molecule, and they must be within close proximity of each other in the molecule. For example, intramolecular hydrogen bonding occurs in ethylene glycol (C2H4(OH)2 ) between its two hydroxyl groups due to the molecular geometry. Intermolecular hydrogen bonds: Intermolecular hydrogen bonds occur between separate molecules in a substance. They can occur between any number of like or unlike molecules as long as hydrogen donors and acceptors are present an in positions in which they can interact. For example, intermolecular hydrogen bonds can occur between NH3 molecules alone, between H2O molecules alone, or between NH3 and H2O molecules." #chemistry #chemtok #chemistrylab #genchem #hydrogen