Name: how blood carries carbon dioxide
Uploaded: 2024-09-12T13:22:46.000Z
Duration: 1 min 19 s
Channel: JoVE

K12 Standards

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Ohio’s Learning Standards and Model Curriculum

9-12

Human Anatomy and Physiology

Absorption And Excretion

Respiratory System

Carbon Dioxide Transport in the Blood

Kohlendioxid wird auf drei Arten vom Gewebe in die Lunge transportiert.
Etwa 7-10% reisen im Plasma gelöst.
Über 20% sind an Hämoglobin gebunden und bilden Carbaminohämoglobin, das durch ein relativ höheresP-CO2 im Gewebe ausgelöst wird.
Umgekehrt führt ein relativ niedrigeresP-CO2 in den Lungenkapillaren zur Dissoziation von Carbaminohämoglobin und zur Freisetzung von CO2. 
Das verbleibende CO2 wandert als Bikarbonat-Ionen im Blut.
Das meiste CO2, das in die roten Blutkörperchen gelangt, wird durch das Enzym Carboanhydrase in Kohlensäure katalysiert. Die Kohlensäure dissoziiert dann in Bikarbonat- und Wasserstoffionen.
Die Bikarbonat-Ionen diffundieren schnell aus den roten Blutkörperchen.
Im Gegenzug gelangen Chloridionen durch die Chloridverschiebung in die roten Blutkörperchen, um die Ladungen in den roten Blutkörperchen zu neutralisieren.
Bikarbonat-Ionen wandern mit dem Blut in die Lunge, wo das niedrigeP-CO2 ihren Wiedereintritt in die roten Blutkörperchen auslöst. Der gesamte Prozess kehrt sich um und setzt das CO2 frei.

kohlendioxidtransport im blut

Der Transport von Kohlendioxid (CO_2) im Blut ist für die menschliche Physiologie von entscheidender Bedeutung. Durchschnittlich produzieren unsere Körperzellen etwa 200 ml CO_2 pro Minute, genau die Menge, die von der Lunge ausgeschieden wird. Dieser Prozess beinhaltet den Transport von CO_2 von den Gewebezellen zur Lunge in drei Hauptformen.

Formen des CO_2-Transports

<ol>
	<li>Gelöst im Plasma: Ein kleiner Prozentsatz (7–10 %) des C_O2 wird transportiert und direkt im Plasma gelöst.</li>
	<li>Carbaminohämoglobin: Knapp über 20 % des CO_2 ist chemisch an Hämoglobin gebunden und bildet Carbaminohämoglobin. Bei diesem Vorgang bindet sich CO_2 direkt an die Aminosäuren des Globins und nicht an den Häm-Teil des Hämoglobins. pCO_2-Werte beeinflussen die Bildung von Carbaminohämoglobin erheblich. Hohe pCO_2-Werte in Gewebekapillaren fördern die Bildung von Carbaminohämoglobin, während niedrige pCO_2-Werte in den Lungenkapillaren die Trennung von CO_2 vom Globin erleichtern, sodass es durch Diffusion in die Alveolen gelangen kann.</li>
	<li>Bicarbonat-Ionen (HCO_3-): Etwa 70 % des CO_2 werden als Bicarbonat-Ionen im Blutplasma transportiert. Dieser Prozess beginnt, wenn CO_2 in systemische Kapillaren diffundiert und in die roten Blutkörperchen eindringt, wo es unter dem Einfluss des Enzyms Carboanhydrase mit Wasser reagiert und Kohlensäure bildet. Diese Säure dissoziiert dann in H^+ und HCO3-. In der Lunge kehrt sich der Prozess um und CO_2 wird freigesetzt und ausgeatmet.</li>
</ol>

Der Haldane-Effekt

Die Menge an CO_2, die im Blut transportiert wird, wird stark vom Grad der Sauerstoffsättigung des Blutes beeinflusst, was als Haldane-Effekt bekannt ist. Dieser Effekt besagt, dass ein niedrigerer pO_2-Wert und eine niedrigere Sauerstoffsättigung des Hämoglobins es dem Blut ermöglichen, mehr CO_2 zu transportieren, da unter diesen Bedingungen eine erhöhte Affinität des Hämoglobins zu CO_2 besteht.

Zusammenfassung

Der Transport von CO_2 im Blut ist ein komplexer, aber effizienter Prozess, der in erster Linie die Bildung von Carbaminohämoglobin und Bicarbonat-Ionen beinhaltet. Dieses komplexe System sorgt dafür, dass der Körper ein stabiles Gleichgewicht zwischen CO_2-Produktion und -Ausstoß aufrechterhält, ein Beweis für die bemerkenswerten Regulierungsmechanismen des Körpers, die für optimale physiologische Funktionen entscheidend sind.

Kohlendioxidtransport im Blut

Kohlendioxid wird auf drei Arten vom Gewebe in die Lunge transportiert.
Etwa 7-10% reisen im Plasma gelöst.
Über 20% sind an Hämoglobin gebunden und bilden ...

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The Respiratory System

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KEY TERMS AND CONCEPTS

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how blood carries carbon dioxide

Carbon dioxide is carried in the blood from body tissues to the lungs. Cells make about 200 mL of CO2 each minute, and the lungs remove about the same amount. The blood moves this waste gas in three main forms.

A small amount, about 7-10%, stays dissolved in the plasma. Just over 20% binds to hemoglobin and forms carbaminohemoglobin. In this case, CO2 attaches to the amino acids of globin, not to the heme part of hemoglobin.

The rest, about 70%, is carried as bicarbonate ions, or HCO3-. CO2 diffuses into systemic capillaries and enters red blood cells. There, carbonic anhydrase helps CO2 react with water to form carbonic acid, which then splits into H+ and HCO3-. In the lungs, the reaction reverses, and CO2 is released so it can be exhaled.

Blood CO2 transport also depends on oxygen levels. This relationship is called the Haldane effect. When pO2 is low and hemoglobin is less saturated with oxygen, blood can carry more CO2 because hemoglobin has a higher affinity for CO2 in those conditions.

How Blood Carries Carbon Dioxide

overview of respiratory system

How Breathing Moves Air and Gases

The respiratory system moves air in and out of the body and exchanges oxygen and carbon dioxide with the environment. This gas exchange is part of respiration, which is essential for life. The system supplies the blood with oxygen so it can carry that oxygen to the rest of the body. Breathing starts when air enters through the nose or mouth. The nose and nasal cavity form the main external opening and the first part of the airway. Air then passes through the pharynx, or throat, which is shared...

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carbon dioxide transport in the blood

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key terms and concepts

Learn how carbon dioxide moves in the blood as dissolved gas, carbaminohemoglobin, and bicarbonate ions, plus how the Haldane effect affects transport.

How Blood Carries Carbon Dioxide | JoVE K12

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Digestive System

How Blood Carries Carbon Dioxide

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