Principles of Agricultural Science – Plant
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Principles of Agricultural Science – Plant
Internal Parts and Function of
Leaves
Unit 4 – Anatomy and Physiology
Lesson 4.4 Leave It to Leaves
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What Leaves Do…
Major functions that leaves provide are:
Transpiration
Photosynthesis
Food storage
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How the Leaf Does It…
Parker, 2004
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Internal Parts
• Epidermis
– Skin or barrier to prevent injury to leaf cells
• Palisade cells
– Cells primarily responsible for photosynthesis
• Spongy mesophyll
– Adds structure to leaf
• Stomata
– Pores allowing the plant to breath
– Stomata are used to cool the plant through the
process of transpiration
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Solar Panels
Leaves collect sun energy using chlorophyll
found in plant cell organelles (chloroplasts)
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Food Production
Plants use the energy from the sun to
convert water and carbon dioxide into
sugar (glucose), water, and oxygen.
Do you know what the process of making
food in this manner is called?
Photosynthesis
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Food Storage
Glucose produced during photosynthesis is
stored in plant parts as an energy source
to be available when needed.
In the leaf, glucose is converted to cellulose
and stored in leaf cells.
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Future Lessons
Related concepts to leaves will be explored
in more detail:
• Lesson 6.3 Lighting It Up will examine light
and photosynthesis
• Lesson 6.4 Chilly Lilies will examine
temperature and transpiration
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Reference
Parker, R. (2004). Introduction to plant
science (Rev. ed.). Clifton Park, NY:
Delmar.
Parker, R. (2010). Plant and soil science:
Fundamentals and applications. Clifton
Park, NY: Delmar.
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