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Information about Bohr Effect

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Oxyhemoglobin Dissociation Curve. Dotted red line corresponds with shift to the right caused by Bohr effect.
The Bohr effect is a property of hemoglobin first described by the Danish physiologist Christian Bohr in 1904, and often erroneously attributed to his son, physicist Niels Bohr, which states that in the presence of carbon dioxide, the oxygen affinity for dissociation of respiratory pigments, such as hemoglobin decreases; because of the Bohr effect, an increase in blood carbon dioxide level or a decrease in pH causes hemoglobin to bind to oxygen with less affinity.

This effect facilitates oxygen transport as hemoglobin binds to oxygen in the lungs, but then releases it in the tissues, particularly those tissues in most need of oxygen. When a tissue's metabolic rate increases, its carbon dioxide production increases. The carbon dioxide is quickly converted into bicarbonate molecules and acidic protons by the enzyme carbonic anhydrase:

CO2+ H2O H+ + HCO3−


This causes the pH of the tissue to decrease, and so increases the dissociation of oxygen from hemoglobin, allowing the tissue to obtain enough oxygen to meet its demands.

The dissociation curve shifts to the right when carbon dioxide or hydrogen ion concentration is increased. This facilitates increased oxygen dumping. This makes sense because increased CO2 concentration and lactic acid build-up occur when the muscles need more oxygen. Changing hemoglobin's oxygen affinity is the body's way of adapting quickly to this problem.

In the Hiroshima variant hemoglobinopathy the Bohr effect is diminished so the hemoglobin has a higher affinity for oxygen and tissue may suffer minor oxygen starvation during high work.

See also

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Respiratory system, physiology: respiratory physiology
Volumeslung volumes - vital capacity - functional residual capacity - respiratory minute volume - dead space - spirometry - body plethysmography - peak flow meter
Airwaysventilation (V) (positive pressure) - breath (inhalation, exhalation) -respiratory rate - respirometer - pulmonary surfactant - compliance - hysteresivity - airway resistance
Bloodpulmonary circulation - perfusion (Q) - hypoxic pulmonary vasoconstriction - pulmonary shunt
Interactionsventilation/perfusion ratio (V/Q) and scan - zones of the lung - gas exchange - pulmonary gas pressures - alveolar gas equation - hemoglobin - oxygen-haemoglobin dissociation curve (2,3-DPG, Bohr effect, Haldane effect) - carbonic anhydrase (chloride shift) - oxyhemoglobin - respiratory quotient - arterial blood gas - diffusion capacity - Dlco
Control of respirationpons (pneumotaxic center, apneustic center) - medulla (dorsal respiratory group, ventral respiratory group) - chemoreceptors (central, peripheral) - pulmonary stretch receptors - Hering-Breuer reflex
Insufficiencyhigh altitude - oxygen toxicity - hypoxia
Hemoglobin, also spelled haemoglobin and abbreviated Hb, is the iron-containing oxygen-transport metalloprotein in the red blood cells of the blood in vertebrates and other animals.
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Christian Bohr (1855-1911) was the father of the famous Danish physicist Niels Bohr, as well as the famous mathematician Harald Bohr. He married Ellen Adler in 1881.

Personal life


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Niels Bohr

Niels Henrik David Bohr
Born September 7 1885(1885--)
Copenhagen, Denmark
Died November 18 1962 (aged 77)
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Hemoglobin, also spelled haemoglobin and abbreviated Hb, is the iron-containing oxygen-transport metalloprotein in the red blood cells of the blood in vertebrates and other animals.
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Carbon dioxide is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. It is a gas at standard temperature and pressure and exists in Earth's atmosphere in this state.
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    pH is a measure of the acidity or alkalinity of a solution. Aqueous solutions at 25 ℃ with a pH less than seven are considered acidic, while those with a pH greater than seven are considered basic (alkaline). The pH of 7.
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    Hemoglobin, also spelled haemoglobin and abbreviated Hb, is the iron-containing oxygen-transport metalloprotein in the red blood cells of the blood in vertebrates and other animals.
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    2, −1
    (neutral oxide)
    Electronegativity 3.44 (Pauling scale)
    Ionization energies
    (more) 1st: 1313.9 kJmol−1
    2nd: 3388.3 kJmol−1
    3rd: 5300.5 kJmol−1

    Atomic radius 60 pm
    Atomic radius (calc.
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    oxygen-haemoglobin dissociation curve plots the proportion of haemoglobin in its saturated form on the vertical axis against the prevailing oxygen tension on the horizontal axis.

    Sigmoidal shape

    It is usually a sigmoid plot.
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    Carbon dioxide is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. It is a gas at standard temperature and pressure and exists in Earth's atmosphere in this state.
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    Hemoglobinopathy is a kind of genetic defect that results in abnormal structure of one of the globin chains of the hemoglobin molecule. Most common hemoglobinopathies include sickle-cell disease.
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    The Haldane effect is a property of hemoglobin first described by the British physician John Scott Haldane.

    Deoxygenation of the blood increases its ability to carry carbon dioxide; this property is the Haldane effect.
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    respiratory system generally includes tubes, such as the bronchi, used to carry air to the lungs, where gas exchange takes place. A diaphragm pulls air in and pushes it out. Respiratory systems of various types are found in a wide variety of organisms.
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    Human physiology is the science of the mechanical, physical, and biochemical functions of humans in good health, their organs, and the cells of which they are composed. The principal level of focus of physiology is at the level of organs and systems.
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    Respiratory physiology is the branch of human physiology focusing upon respiration.

    Topics include:

    Volumes

    • lung volumes
    • vital capacity
    • functional residual capacity
    • dead space
    • spirometry
    • body plethysmography
    • peak flow meter


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    Larger volumes Smaller volumes
    males females
    taller people shorter people
    non-smokers heavy smokers
    professional athletes[1] non-athletes
    people living at high altitudes people living at low altitudes
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    Vital capacity is the maximum volume of air that a person can exhale after maximum inhalation. It can also be the maximum volume of air that a person can inhale after maximum exhalation.
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    Functional Residual Capacity (FRC) is the volume of air present in the lungs at the end of passive expiration. At FRC, the elastic recoil forces of the lungs and chest wall are equal but opposite and there is no exertion by the diaphragm or other respiratory muscles.
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    Respiratory minute volume (or minute ventilation, or flow of gas) is the volume of air which can be inhaled (inhaled minute volume) or exhaled (exhaled minute volume) from a person's lungs in one minute.
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    dead space is air that is inhaled by the body in breathing, but does not partake in gas exchange.

    In adults, it is usually in the range of 150ml.[1]

    Understanding dead space


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    Spirometry (meaning the measuring of breath) is the most common of the Pulmonary Function Tests (PFTs), measuring lung function, specifically the measurement of the amount (volume) and/or speed (flow) of air that can be inhaled and exhaled.
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    The introduction to this article provides insufficient context for those unfamiliar with the subject matter.
    Please help [ improve the introduction] to meet Wikipedia's layout standards.

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    A peak flow meter is a small, hand-held device used to manage asthma by monitoring airflow through the bronchi and thus the degree of restriction in the airways. The peak flow meter measures the patient's maximum ability to expel air from the lungs, or
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    ventilation (or ventilation rate) is the rate at which gas enters or leaves the lung. It is categorised under the following definitions:

    Measurement Equation Description
    Minute ventilation = tidal volume * respiratory rate[1]
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    Positive pressure ventilators help patients with respiratory problems to breathe easier. They use high pressure gas at the opening of the patients lungs in order to mobilize oxygen flow down the pressure gradient, and into the patient's lungs.
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    Breathing transports oxygen into the body and carbon dioxide out of the body. Aerobic organisms require oxygen to create energy via respiration, in the form of energy-rich molecules such as glucose. The medical term for normal relaxed breathing is eupnoea.
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    Inhalation (also known as inspiration) is the movement of air from the external environment, through the airways, into the alveoli during breathing.

    Inhalation begins with the onset of contraction of the diaphragm, which results in expansion of the intrapleural space
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    Exhalation (or expiration) is the movement of air out of the bronchial tubes, through the airways, to the external environment during breathing.

    Exhaled air is rich in carbon dioxide, a waste product of cellular respiration during the production of ATP.
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    respiratory rate (or respiration rate) is the number of breaths a living being, such as a human, takes per minute.

    There is only limited research on monitoring alien respiratory rate, and these studies have focused on such issues as the inaccuracy of respiratory rate
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    A respirometer is a device used to measure the rate of respiration of a living organism by measuring its rate of exchange of oxygen and carbon dioxide. They allow investigation into how factors such as age or the effect of light affect the rate of respiration.
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