BBC Learning Zone Clips

CLIP 13885

Abscission – Why do plants shed their leaves in autumn?

Abscission – Why do plants shed their leaves in autumn?
Key Info
  • Abscission – Why do plants shed their leaves in autumn?
  • Duration: 02:09
  • Chris Packham explains why deciduous trees drop their leaves every autumn. The leaf is a fragile organ and is at risk from desiccation and freezing during winter months. To prevent damage, most deciduous trees shed their leaves in a process known as abscission. The tree first withdraws valuable pigments like chlorophyll from the leaf before forming a thin band of dead cells at the base of the stem, separating the leaf from the stalk. The leaf tissue then dies and drops to the forest floor where it decomposes, any useful nutrients can then be reabsorbed through the roots.
  • Subject:



    Bio: Plants - Physiology

  • Keywords: tree, plant, leaf, photosynthesis, abscission, autumn, seasons
Ideas for use in class
  • Could be used to introduce children to the process of abscission or an example of how plants have adapted to live in a variable climate.
Background details
  • Clip language : English
  • Aspect ratio : 16x9

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