Activation Energy and Enzymes TITLE: Activation Energy and EnzymesSOURCE: Freeman, S, Biological Science, Second Edition, Pearson Prentice Hall, Inc.© 2006 Pearson Prentice Hall, Inc.KEYWORDS: Activation energy, enzymes, exergonic reactions, ATP, activation energy, catalysts, lock-and-key model, induced-fit model Electron Microscopy Interactive Java Tutorials - Virtual Scanning Electron Microscopy Interactive Java Tutorials Virtual Scanning Electron Microscopy We have teamed up with award-winning electron microscopist Dr. Dennis Kunkel to produce a series of interactive Java tutorials that explore various aspects of virtual Scanning Electron Microscopy (vSEM).
Biology Animations Carnegie Mellon's Office of Technology for Education and Department of Biological Sciences create multimedia materials for teaching and learning Biology. After an analysis of a number of Biology courses was performed to identify when and how shared concepts where taught, a team of biologists, media programmers, and learning experts came together to create animations designed to improve understanding of some of the main concepts taught in Modern Biology and Biochemistry. Phosopholipid Membranes Cell Size and Scale Some cells are visible to the unaided eye The smallest objects that the unaided human eye can see are about 0.1 mm long. That means that under the right conditions, you might be able to see an ameoba proteus, a human egg, and a paramecium without using magnification. A magnifying glass can help you to see them more clearly, but they will still look tiny.
Spinning-disk microscope offers window into the center of cell A new method of imaging cells is allowing scientists to see tiny structures inside the 'control centre' of the cell for the first time. The microscopic technique, developed by researchers at Queen Mary University of London, represents a major advance for cell biologists as it will allow them to investigate structures deep inside the cell, such as viruses, bacteria and parts of the nucleus in depth. Recent advances in optical physics have made it possible to use fluorescent microscopy to study complex structures smaller than 200 nanometres (nm) -- around 500 times smaller than the width of a human hair. These methodologies are called super-resolution microscopy. The drawback of such techniques is that they can only produce very clear images of structures that are at the bottom of the cell. This study shows how these issues have been overcome with a newly developed imaging system, making it possible to image structures as small as 80nm or less anywhere in the cell.
Size of the Nanoscale Just how small is “nano?” In the International System of Units, the prefix "nano" means one-billionth, or 10-9; therefore one nanometer is one-billionth of a meter. It’s difficult to imagine just how small that is, so here are some examples: A sheet of paper is about 100,000 nanometers thick A strand of human DNA is 2.5 nanometers in diameter There are 25,400,000 nanometers in one inch A human hair is approximately 80,000- 100,000 nanometers wide A single gold atom is about a third of a nanometer in diameter On a comparative scale, if the diameter of a marble was one nanometer, then diameter of the Earth would be about one meter One nanometer is about as long as your fingernail grows in one second The illustration below has three visual examples of the size and the scale of nanotechnology, showing just how small things at the nanoscale actually are.
Bats Use Rolled-Up Leaves as “Trumpets” By Ker Than- A species of tiny bat seems to be using rolled-up leaves like trumpets to amplify calls, a new study says. A few years ago, biologists Gloriana Chaverri and Erin Gillam were in Costa Rica studying Spix’s disk-winged bat, a species that is known to escape predators and harsh weather by roosting inside the folded leaves of plants such as the lobster-claws plant and calatheas. Nuclear reactor and power plant simulation Introduction This is not a lesson like the others in Radioactivity and Atomic Physics Explained but it fits in well with the lesson on nuclear power. It is a very sophisticated simulation of a pressurised water reactor (PWR), which is the most common type of nuclear power reactor in the US but not in Europe, though the principles are very similar. Using the tour
Report suggests slowdown in CO2 emissions rise 31 October 2013Last updated at 05:19 ET By Matt McGrath Environment correspondent, BBC News Carbon emissions from coal fired plants like this one continue to increase but at a lower rate than previous years Global emissions of carbon dioxide may be showing the first signs of a "permanent slowdown" in the rate of increase.
The PCR Method - a DNA Copying Machine Lists of Nobel Prizes and Laureates The PCR Method - a DNA Copying Machine Play the Eye of the Donkey Game About the game PCR is a method by which a few fragments of DNA can be duplicated into millions in a couple of hours.