Photosynthesis in a C4 plant

Référence de la vidéo 11938278
Photosynthesis in a C4 plant. Animation showing the C4 mechanism by which certain plants fix carbon from the atmosphere in a form of photosynthesis. At upper left, carbon dioxide (CO2) enters the plant through stomata, diffusing into the intercellular space and absorbed by mesophyll cells (lower left). The CO2 combines with phosphoenolpyruvate, a three-carbon compound (C3), to form (via oxalacetate) a four-carbon (C4) compound malate (number of carbon atoms indicated by black dots). After reduction, the C4 compound moves into the bundle sheath cells (lower centre). There, it is oxidized and split into a C3 compound (pyruvate) and CO2. The C3 compound moves back to the mesophyll cell and is converted, by a reaction driven by adenosine triphosphate (ATP), into phosphoenolpyruvate. The CO2 is fed into the Calvin cycle (orange) in the bundle sheath cell, where the energy from chloroplasts is used to form carbohydrates such as sugars that enter the phloem tubes (pink, upper right). C4 photosynthesis is a more evolved process than C3 photosynthesis. It first emerged around 30 million years ago, and despite only representing 3-5 percent of Earth's plant biomass and species, it accounts for around 30 percent of terrestrial carbon fixation. For this animation without labels, see K004/4154.
Licence : Droits gérés
Crédit : Science Photo Library / Biocosmos / Francis Leroy & Sempot Amaury
Model Release : Non requis
Durée : 26 Secondes
Aspect ratio : 16/9
Restrictions : -

Prix pour cette vidéo À partir de 70 €

Publicité (Communication d'entreprise etc) À partir de 70 €
Rédactionnel (Sites web multiples etc) À partir de 125 €
Médias (Émission TV, Divertissement TV etc) À partir de 150 €

Mots-clés

;