Anonymous View

Anonymous View

Flux (biology)

In general, flux in biology relates to movement of a substance between compartments. There are several cases where the concept of flux is important.

  • The movement of molecules across a membrane: in this case, flux is defined by the rate of diffusion or transport of a substance across a permeable membrane. Except in the case of active transport, net flux is directly proportional to the concentration difference across the membrane, the surface area of the membrane, and the membrane permeability constant.
  • In ecology, flux is often considered at the ecosystem level - for instance, accurate determination of carbon fluxes using techniques like eddy covariance (at a regional and global level) is essential for modeling the causes and consequences of global warming.
  • Metabolic flux refers to the rate of flow of metabolites through a biochemical network, along a linear metabolic pathway, or through a single enzyme. A calculation may also be made of carbon flux or flux of other elemental components of biomolecules (e.g. nitrogen). The general unit of flux is chemical mass /time (e.g., micromole/minute; mg/kg/minute). Flux rates are dependent on a number of factors, including: enzyme concentration; the concentration of precursor, product, and intermediate metabolites; post-translational modification of enzymes; and the presence of metabolic activators or repressors. Metabolic flux in biologic systems can refer to biosynthesis rates of polymers or other macromolecules, such as proteins, lipids, polynucleotides, or complex carbohydrates, as well as the flow of intermediary metabolites through pathways Metabolic control analysis and flux balance analysis provide frameworks for understanding metabolic fluxes and their constraints.
    • Read more
    This page contains text from Wikipedia, the Free Encyclopedia - https://wn.com/Flux_(biology)

    Flux (metabolism)

    Flux, or metabolic flux is the rate of turnover of molecules through a metabolic pathway. Flux is regulated by the enzymes involved in a pathway. Within cells, regulation of flux is vital for all metabolic pathways to regulate the pathway's activity under different conditions. Flux is therefore of great interest in metabolic network modelling, where it is analysed via flux balance analysis.

    In this manner, flux is the movement of matter through metabolic networks that are connected by metabolites and cofactors, and is therefore a way of describing the activity of the metabolic network as a whole using a single characteristic.

    Metabolic Flux

    It is easiest to describe the flux of metabolites through a pathway by considering the reaction steps individually.The flux of the metabolites through each reaction (J) is the rate of the forward reaction (Vf), less that of the reverse reaction (Vr).

    J=Vf-Vr

    At equilibrium, there is no flux. Furthermore, it is observed that throughout a steady state pathway, the flux is usually determined by the rate determining step of the reaction.

    Read more
    This page contains text from Wikipedia, the Free Encyclopedia - https://wn.com/Flux_(metabolism)

    Scout

    A scout is a soldier performing reconnaissance and other support duties.

    Scout may also refer to:

    Aircraft

  • Scout (aircraft), pre-1920s (British) terminology for a single-seat fighter
  • Scout plane, post-1920s/modern usage for reconnaissance or surveillance aircraft
  • Aeryon Scout, a micro UAV
  • AD Scout British naval aircraft
  • Aeronca K Scout
  • American Champion Scout
  • Eagles Wing Scout, an American powered parachute
  • IAI Scout, an unmanned air vehicle used by the Israel Defense Forces during the 1982 Lebanon War
  • Tennessee Propellers Scout, an American powered parachute design
  • Westland Scout British helicopter

    • Automotive and rail

  • International Harvester Scout
  • Scout (train)

    • Professions

  • A domestic assistant at Oxford University, see bedder
  • Reconnaissance
  • Scout (sport), a professional sports talent-scout
  • Scout.com, a sports-publishing company

    • Land military

  • Scout rifle
  • Scout SV, armoured fighting vehicle
  • Steyr Scout, rifle

    • Space applications

  • Scout (rocket family)
  • Mars Scout Program

    • Ships

  • HMS Scout, the name of various British Royal Navy ships
    • Read more
    This page contains text from Wikipedia, the Free Encyclopedia - https://wn.com/Scout

    Team Fortress 2

    Team Fortress 2 is a team-based first-person shooter multiplayer video game developed and published by Valve Corporation. It is the sequel to the 1996 mod Team Fortress for Quake and its 1999 remake. It was released as part of the video game compilation The Orange Box on October 10, 2007 for Windows and the Xbox 360. A PlayStation 3 version followed on December 11, 2007. On April 8, 2008, it was released as a standalone title for Windows. The game was updated to support OS X on June 10, 2010, and Linux on February 14, 2013. It is distributed online through Valve's download retailer Steam; retail distribution was handled by Electronic Arts.

    In Team Fortress 2, players join one of two teams comprising nine character classes, battling in a variety of game modes including capture the flag and king of the hill. The development is led by John Cook and Robin Walker, creators of the original Team Fortress. Announced in 1998, the game once had more realistic, militaristic visuals and gameplay, but this changed over the protracted nine-year development. After Valve released no information for six years, Team Fortress 2 regularly featured in Wired News' annual vaporware list among other ignominies. The finished Team Fortress 2 has cartoon-like visuals influenced by the art of J. C. Leyendecker, Dean Cornwell and Norman Rockwell and is powered by Valve's Source engine.

    Read more
    This page contains text from Wikipedia, the Free Encyclopedia - https://wn.com/Team_Fortress_2

    Scout (train)

    The Scout was one of the named passenger trains of the Atchison, Topeka and Santa Fe Railway. It started as train Nos. 1 (westbound) & 10 (eastbound) between Chicago, Illinois and Los Angeles, California. Inaugurated on January 16, 1916, this "budget" heavyweight train had tourist sleeping cars with upper and lower berths, "chair" cars (coaches) and an open-end observation car.

    The train was assigned Nos. 1 & 2 in 1920 and reverted to Nos. 1 & 10 a year later. In summer 1926 it left Chicago at 1115 and arrived Los Angeles at 0900 three days later, running via Ottawa Jct, Amarillo and Fullerton. In November 1939 it left at 2045 and arrived 0700, sixty hours on the same route except via Pasadena.

    The Scout made its last run on June 7, 1948.

    History

    Timeline

  • January 19, 1916: The Scout commences operation.
  • 1920: The eastbound Scout is assigned No. 2, but becomes No. 10 the following year.
  • January 4, 1931: The Scout is discontinued during the Great Depression. Thereafter, economy service was provided by the Hopi, the Missionary, and the Navajo.
    • Read more
    This page contains text from Wikipedia, the Free Encyclopedia - https://wn.com/Scout_(train)

    Podcasts:

    Email this Page Play all in Full Screen Show More Related Videos
    PLAYLIST TIME:
    ×
    ×
    ×
    ×