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Published on: May 23, 2011
Circuntación observada sin una fuerza gravitacional significativa en vuelos espaciales.
1Department of Biology, University of Pennsylvania, Philadelphia 19104-4288, USA.
Resumen
El movimiento de los órganos de las plantas, llamado circunnotación, fue estudiado en el espacio. Los resultados muestran que la gravedad no es necesaria para que ocurra la circunnotación en los hipocotilos de girasol.
Área de la Ciencia:
- Fisiología vegetal Fisiología vegetal
- Biología espacial Biología espacial.
- Biología gravitacional y biología gravitacional.
Sus antecedentes:
- La circunctación, un mecanismo ubicuo en el crecimiento de los órganos de las plantas, ha sido objeto de debate con respecto a su dependencia de la gravedad.
- Investigaciones anteriores sugirieron que los experimentos en casi ingravidez podrían resolver este debate.
Objetivo del estudio:
- Para determinar si la gravedad es esencial para el inicio y el mantenimiento de la circunnotación en las plantas.
- Investigar el papel de los estímulos gravitacionales en los procesos de crecimiento diferencial que conducen a las oscilaciones circunnacionales.
Principales métodos:
- Se llevó a cabo un experimento en la misión Spacelab 1 para observar el crecimiento de las plantas en un entorno de microgravedad.
- Los hipocótilos de girasol se utilizaron como sujetos de prueba para estudiar las oscilaciones circumnutational.
Principales resultados:
- Las oscilaciones circumnutational se observaron con éxito en hipocótilos de girasol durante la misión espacial.
- Los hallazgos demostraron que la entrada gravitacional continua no es necesaria para la circunnotación.
Conclusiones:
- Los estímulos gravitacionales no son necesarios para el inicio o el mantenimiento de la circunnotación en los hipocotilos de girasol.
- Este hallazgo desafía las hipótesis de larga data sobre el papel de la gravedad en el movimiento de las plantas.
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