#20: AIDS Virus Has an Ancient History | HIV & AIDS HIV is a newcomer among human pathogens, having caused the first known cases of aids within the past few decades. So scientists suspected that SIV, the primate virus that spawned HIV, was just a few hundred years older. Tulane University virologist Preston Marx published research in September that suggests otherwise: SIV seems to be at least 32,000 years old, meaning it coexisted with people nearly all that time before HIV emerged. Marx’s team did SIV tests on monkeys from Bioko Island, which was cut off from the African continent 10,000 years ago. If we do not figure out what triggered the HIV epidemic, it will be hard to prepare for what might come next.
Cell biology Understanding cells in terms of their molecular components. Knowing the components of cells and how cells work is fundamental to all biological sciences. Appreciating the similarities and differences between cell types is particularly important to the fields of cell and molecular biology as well as to biomedical fields such as cancer research and developmental biology. Processes[edit] Movement of proteins[edit] Endothelial cells under the microscope. Each type of protein is usually sent to a particular part of the cell. Extracellular and cell surface proteins destined to be degraded can move back into intracellular compartments upon being incorporated into endocytosed vesicles, some of which fuse with lysosomes where the proteins are broken down to their individual amino acids. Other cellular processes[edit] Internal cellular structures[edit] Techniques used to study cells[edit] There are several different methods used in the study of cells: Notable cell biologists[edit] See also[edit]
Step into the Movies with Tours in New York, London and Los Angeles - Nightly When you travel this spring, you can take a trip into your favorite movie by taking a walking or chauffeur-driven tour of New York, London or Los Angeles. Whether you‘re a fan of gangster movies, comic books, wizards or just celebrities, each of these cities has a tour to fulfill your greatest fantasies. Keep reading below for just a few of the ways you can follow in the footsteps of pop culture! 1. The New York Gangster Chauffeur Driven Tour If you’re a fan of movies such as “The Godfather”, “Goodfellas”, “Donnie Brasco” and “American Gangster,” you’ll love this sightseeing tour in New York. 2. You can take a mystical journey of one of the most amazing cities in the world: London. 3. Walk among the stars as you take a tour through the streets and activities in Los Angeles.
Macromolecule Very large molecule, such as a protein A macromolecule is a very large molecule important to biological processes, such as a protein or nucleic acid. It is composed of thousands of covalently bonded atoms. Many macromolecules are polymers of smaller molecules called monomers. The most common macromolecules in biochemistry are biopolymers (nucleic acids, proteins, and carbohydrates) and large non-polymeric molecules such as lipids, nanogels and macrocycles.[1] Synthetic fibers and experimental materials such as carbon nanotubes[2][3] are also examples of macromolecules. Definition[edit] MacromoleculeLarge moleculeA molecule of high relative molecular mass, the structure of which essentiallycomprises the multiple repetition of units derived, actually or conceptually, frommolecules of low relative molecular mass. Usage of the term to describe large molecules varies among the disciplines. Because of their size, macromolecules are not conveniently described in terms of stoichiometry alone.
Can a Simple Model Explain the Advent of Cells? Scientists still don't know how a few biomolecules got together to kick-start life. Now a pair of theoretical biophysicists have come up with a simple mathematical model of two interacting chemicals that seems to replicate an essential part of the rise of life: the emergence of primitive, reproducing "protocells." The first task in sparking life, or at least lifelike chemical interactions, would be to coax complex molecules to reproduce themselves from the other chemicals in solution around them. Under the right conditions, some proteins and other complex molecules can produce copies of themselves by purely chemical means. That's because in the process, numerous copying errors, or mutations, arise. Of course, nature found a way around this problem, and over the years scientists have proposed several refinements to make their models more stable. But this model, too, has a problem.
Biochemistry Biochemistry is closely related to molecular biology, the study of the molecular mechanisms by which genetic information encoded in DNA is able to result in the processes of life. Depending on the exact definition of the terms used, molecular biology can be thought of as a branch of biochemistry, or biochemistry as a tool with which to investigate and study molecular biology. Much of biochemistry deals with the structures, functions and interactions of biological macromolecules, such as proteins, nucleic acids, carbohydrates and lipids, which provide the structure of cells and perform many of the functions associated with life. The chemistry of the cell also depends on the reactions of smaller molecules and ions. These can be inorganic, for example water and metal ions, or organic, for example the amino acids which are used to synthesize proteins. History[edit] Starting materials: the chemical elements of life[edit] Biomolecules[edit] Carbohydrates[edit] Lipids[edit] Proteins[edit]
Sucralose - Wikipedia, the free encyclopedia - Nightly Comparison of the chemical structures of sucrose (top) and sucralose (bottom) Sucralose is an artificial sweetener. The majority of ingested sucralose is not broken down by the body, so it is noncaloric.[4] In the European Union, it is also known under the E number (additive code) E955. History[edit] Sucralose was discovered in 1976 by scientists from Tate & Lyle, working with researchers Leslie Hough and Shashikant Phadnis at Queen Elizabeth College (now part of King's College London).[4] While researching ways to use sucrose and its synthetic derivatives, Phadnis was told to test a chlorinated sugar compound. Tate & Lyle patented the substance in 1976; as of 2008, the only remaining patents concern specific manufacturing processes.[8] Sucralose was first approved for use in Canada in 1991. Production[edit] Tate & Lyle currently manufactures sucralose both at a plant in Jurong, Singapore.[11] and at a recently reopened plant in McIntosh, Alabama. Product uses[edit] Cooking[edit]
Biophysics Study of biological systems using methods from the physical sciences Molecular biophysics typically addresses biological questions similar to those in biochemistry and molecular biology, seeking to find the physical underpinnings of biomolecular phenomena. Scientists in this field conduct research concerned with understanding the interactions between the various systems of a cell, including the interactions between DNA, RNA and protein biosynthesis, as well as how these interactions are regulated. A great variety of techniques are used to answer these questions. Fluorescent imaging techniques, as well as electron microscopy, x-ray crystallography, NMR spectroscopy, atomic force microscopy (AFM) and small-angle scattering (SAS) both with X-rays and neutrons (SAXS/SANS) are often used to visualize structures of biological significance. Medical physics, a branch of biophysics, is any application of physics to medicine or healthcare, ranging from radiology to microscopy and nanomedicine.
Scientists observe single gene activity in living cells in detail for first time Researchers at Albert Einstein College of Medicine of Yeshiva University have for the first time observed the activity of a single gene in living cells. In an unprecedented study, published in the April 22 online edition of Science, Einstein scientists were able to follow, in real time, the process of gene transcription, which occurs when a gene converts its DNA information into molecules of messenger RNA (mRNA) that go on to make the protein coded by the gene. Robert Singer, Ph.D., co-director of the Gruss Lipper Biophotonics Center at Einstein and professor and co-chair of anatomy and structural biology, is senior author of the paper. The study's lead author is Daniel Larson, Ph.D., previously a member of Dr. Using florescent proteins, the researchers were able to follow mRNA activity by inserting DNA sequences into a gene in live yeast cells. This research was funded by the National Institutes of Health and the National Institute of General Medical Sciences.
Ecology Ecology is an interdisciplinary field that includes biology and Earth science. The word "ecology" ("Ökologie") was coined in 1866 by the German scientist Ernst Haeckel (1834–1919). Ancient Greek philosophers such as Hippocrates and Aristotle laid the foundations of ecology in their studies on natural history. Modern ecology transformed into a more rigorous science in the late 19th century. Ecology is a human science as well. Integrative levels, scope, and scale of organization[edit] Hierarchical ecology[edit] System behaviors must first be arrayed into different levels of organization. O'Neill et al. (1986)[5]:76 The scale of ecological dynamics can operate like a closed system, such as aphids migrating on a single tree, while at the same time remain open with regard to broader scale influences, such as atmosphere or climate. Biodiversity[edit] Biodiversity refers to the variety of life and its processes. Noss & Carpenter (1994)[9]:5 Habitat[edit] Biodiversity of a coral reef. Niche[edit]