fixation

(noun)

The act of uniting chemically with a solid substance or in a solid form; reduction to a non-volatile condition; -- said of gaseous elements.

Related Terms

Examples of fixation in the following topics:

  • Nitrogenase and Nitrogen Fixation

    • Nitrogen fixation also refers to other biological conversions of nitrogen, such as its conversion to nitrogen dioxide.
    • Nitrogen fixation is a process by which nitrogen (N2) in the atmosphere is converted into ammonia (NH3).
    • Fixation processes free up the nitrogen atoms from their diatomic form (N2) to be used in other ways.
    • Therefore, nitrogen fixation is essential for agriculture and the manufacture of fertilizer.
    • Biological nitrogen fixation (BNF) occurs when atmospheric nitrogen is converted to ammonia by an enzyme called nitrogenase.

  • Early Discoveries in Nitrogen Fixation

    • Nitrogen fixation carried out by bacteria helps farmers yield healthy crops.
    • He found that the nodules on the roots of legumes are the location where nitrogen fixation takes place.
    • Hellriegel did not determine what factors in the root nodules carried out nitrogen fixation.
    • These rhizobia perform the chemical processes of nitrogen fixation.
    • Work done by Martinus Beijerinck was key to the discovery of rhizobia, symbiotic bacteria found on the roots of legumes and responsible for nitrogen fixation.

  • Genetics and Regulation of N2 Fixation

    • Through control of gene expression, nitrogen fixing bacteria can turn on and off the proteins needed for nitrogen fixation.
    • The fixation of atmospheric nitrogen (N2) is a very energy intensive endeavor.
    • If there is no need for N2 fixation, the production of proteins needed for fixation are tightly controlled.
    • The nif genes are genes encoding enzymes involved in the fixation of atmospheric nitrogen.
    • Discuss the role of the nif genes in controlling nitrogen fixation

  • Complement Fixation

    • Complement fixation is a method that demonstrates antibody presence in patient serum.
    • Complement fixation is a classic method for demonstrating the presence of antibody in patient serum.
    • The complement fixation test consists of two components.
    • These two components of the complement fixation method are tested in sequence.
    • Describe how the complement fixation assay can be used to test for the presence of a specific antibody in a patient's serum

  • Carboxysomes

    • Carboxysomes are intracellular structures that contain enzymes involved in carbon fixation and found in many autotrophic bacteria.
    • They are proteinaceous structures resembling phage heads in their morphology; they contain the enzymes of carbon dioxide fixation in these organisms.
    • It is thought that the high local concentration of the enzymes, along with the fast conversion of bicarbonate to carbon dioxide by carbonic anhydrase, allows faster and more efficient carbon dioxide fixation than is possible inside the cytoplasm.
    • Carboxysomes are bacterial microcompartments that contain enzymes involved in carbon fixation.
    • These compartments are thought to concentrate carbon dioxide to overcome the inefficiency of RuBisCo (ribulose bisphosphate carboxylase/oxygenase) - the predominant enzyme in carbon fixation and the rate limiting enzyme in the Calvin cycle.

  • Oxygenic Photosynthesis

    • Oxygenic photosynthesis, provides energy to organism and allows for carbon fixation, all the while producing oxygen as a byproduct.
    • Photosynthesis is not only needed by photosynthetic organism for energy but also for carbon fixation .
    • Carbon dioxide is converted into sugars in a process called carbon fixation.
    • Carbon fixation is a redox reaction, so photosynthesis needs to supply both a source of energy to drive this process, and the electrons needed to convert carbon dioxide into a carbohydrate, which is a reduction reaction.

  • The 3-Hydroxypropionate Cycle

    • The 3-hydroxypropionate cycle is a carbon fixation pathway that results in the production of acetyl-CoA and glyoxylate.
    • Carbon fixation is a key pathway in numerous microorganisms, resulting in the formation of organic compounds deemed necessary for cellular processes.
    • One of the pathways that is utilized for carbon fixation is the 3-hydroxypropionate cycle.
    • However, the cycle can be broken down into two major phases, carbon dioxide fixation and glyoxylate assimilation.

  • Intermediates Produced During the Calvin Cycle

    • The Calvin Cycle involves the process of carbon fixation to produce organic compounds necessary for metabolic processes.
    • The Calvin Cycle is characterized as a carbon fixation pathway.
    • The process of carbon fixation involves the reduction of carbon dioxide to organic compounds by living organisms.
    • The Calvin cycle is most often associated with carbon fixation in autotrophic organisms, such as plants, and is recognized as a dark reaction.
    • In organisms that require carbon fixation, the Calvin cycle is a means to obtain energy and necessary components for growth.

  • Regulation of the Calvin Cycle

    • The Calvin cycle is a process that ensures carbon dioxide fixation in plants.
    • The Calvin cycle is a process utilized to ensure carbon dioxide fixation.
    • During the first phase of the Calvin cycle, carbon fixation occurs.
    • The regulation of the Calvin cycle requires many key enzymes to ensure proper carbon fixation.
    • Outline the three major phases of the Calvin cycle: carbon fixation, reduction, and regeneration of ribulose

  • Biosynthesis and Energy

    • Carbon dioxide fixation is necessary to ensure carbon dioxide can be converted into organic carbon.
    • The major pathways utilized to ensure fixation of carbon dioxide include: the Calvin cycle, the reductive TCA cycle, and the acetyl-CoA pathway.