Floral Careers Plant Propagation Light & Photosynthesis

The Electromagnetic Spectrum

Colors of Light that Plants Use Plants absorb red light. Plants absorb blue light. Plants don’t absorb green light, they reflect green light.

Sources of Light Sun Artificial Lights Incandescent bulbs Fluorescent bulbs Specialized lights for plant growth

HID Lights in the Kirkwood Greenhouse

Where in Plants is Light Being Absorbed? Leaves. Sometimes by the stems. Specifically light is absorbed by a chemical compound called chlorophyll.

Chlorophyll A green-colored chemical pigment found in the chloroplasts of plant cells.

Leaf Cross-sectional View Showing Plant Cells with Chloroplasts

Does This Plant Have Chlorophyll?

YES! Chlorophyll is still present in the leaves. It’s presence is masked by the more dominant red and purple pigments.

Autotrophs Living organisms capable of manufacturing their own food. Plants are autotrophs.

Photosynthesis Inputs: Light Water Carbon dioxide Chlorophyll

Photosynthesis Outputs Oxygen Sugar (glucose) = Food See, plants really are autotrophs!

Paul’s Circle of Life

The End