Cannabis Sativa

Respirometer
Purposemeasure the rate of respiration

A respirometer is a device used to measure the rate of respiration[1] of a living organism by measuring its rate of exchange of oxygen and/or carbon dioxide.[2] They allow investigation into how factors such as age, or chemicals affect the rate of respiration.[3] Respirometers are designed to measure respiration either on the level of a whole animal or plant or on the cellular level. These fields are covered by whole animal and cellular (or mitochondrial) respirometry, respectively.[4]

A simple whole plant respirometer designed to measure oxygen uptake or CO2 release consists of a sealed container with the living specimen together with a substance to absorb the carbon dioxide given off during respiration, such as soda lime pellets or cotton wads soaked with potassium hydroxide. The oxygen uptake is detected by manometry.[5] Typically, a U-tube manometer is used, which directly shows the pressure difference between the container and the atmosphere. As an organism takes up O2, it generates a proportionate quantity of CO2 (see respiratory quotient), but all the CO2 is absorbed by the soda lime. Therefore, all of the drop of pressure in the chamber can be attributed to the drop of O2 partial pressure in the container. The rate of change gives a direct and reasonably accurate reading for the organism's rate of respiration.

As changes in temperature or pressure can also affect the displacement of the manometric fluid, a second respirometer identical to the first except with a dead specimen (or something with the same mass as the specimen in place of the organism) is sometimes set up. Subtracting the displacement of the second respirometer from the first allows for control of these factors.

The set up of modern respirometers is described in more detail under respirometry. A respirometer may also be called an oxygraph.[6] Suppliers for whole animal respirometers are e.g. Sable Systems, Respirometer Systems and Applications, Qubit Systems, Eco-environment, Bio-technology, or Challenge Technology; for mitochondrial respirometers, Oroboros Instruments,[7] Hansatech Instruments,[8] or YSI.[9]

See also[edit]

References[edit]

  1. ^ Toole, Glenn; Toole, Sue (2004). Essential A2 Biology for OCR. Nelson Thornes. p. 18. ISBN 9780748785186. Retrieved 23 August 2018.
  2. ^ "Pearson - The Biology Place". www.phschool.com. Retrieved 2019-10-29.
  3. ^ "Measuring the rate of metabolism | Nuffield Foundation". www.nuffieldfoundation.org. Retrieved 2019-10-29.
  4. ^ Beeson, Craig C.; Beeson, Gyda C.; Schnellmann, Rick G. (2010-09-01). "A high-throughput respirometric assay for mitochondrial biogenesis and toxicity". Analytical Biochemistry. 404 (1): 75–81. doi:10.1016/j.ab.2010.04.040. ISSN 1096-0309. PMC 2900494. PMID 20465991.
  5. ^ "Measuring respiratory quotient | Nuffield Foundation". www.nuffieldfoundation.org. Retrieved 2019-10-29.
  6. ^ Djafarzadeh, Siamak; Jakob, Stephan M. (2017-02-08). "High-resolution Respirometry to Assess Mitochondrial Function in Permeabilized and Intact Cells". Journal of Visualized Experiments (120): e54985. doi:10.3791/54985. ISSN 1940-087X. PMC 5408571. PMID 28287504.
  7. ^ "Oroboros: HRR". www.oroboros.at. Retrieved 2019-10-29.
  8. ^ "Chlorolab 3+ System". Hansatech Instruments Ltd. Retrieved 2019-10-29.
  9. ^ Miller, Will (August 29, 2017). "Biosensor Technology". www.ysi.com. Retrieved 2019-10-29.

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