Finding Chlorophyll
Tags: 
chlorophyll
Photosynthesis
Structure and Function
Place of Learning: 
Grade Level: 
Summary: 
This lesson builds upon the previous lessons introducing the process of photosynthesis, focusing on light absorption by leaves to make their own food. The activity has students massage kale leaves, breaking down the cells, and releasing the chlorophyll as the color of the leaves darken with pressure.
Student Learning Goals & Objectives: 

Students will:

  • Observechlorophyll in leaves.
  • Experiment finding the chlorophyll in leaves
Materials & Prep: 
  • Washed Kale Leaves
  • Whisk and Large Bowl
  • Salad Dressind Ingredients (e.g. oil, vinegars, lemon)
  • Small Bowl for Each Student

 

Procedure Steps: 
1
Activity Preparation
  1. Wash kale leaves and gather materials for kale salad dressingf
2
Massaged Kale Salad Brings Out the Chlorophyll
  1. Instruct students to wash their hands and review food safety practices they will need to follow when cooking together.
  2. Distribute kale salad materials to each student and instruct them how to make kale salad by following these steps:
    • Break up kale leaves away from the spine.
    • Add salt and lemon to break down plant cell walls in the leaves.
    • Mash the leaves with your hands until texture becomes soft and the color becomes dark green.
  3. Ask: What do you notice happening to the kale leaves when you massage them? (They get softer, darker green, and watery)
  4. Review the functions of a leaf. Remind students that a leaf’s primary function is toabsorb light and turn it into nutrients for the plant.
  5. Ask: What do you think makes the leaf green? (Chloroplast – it makes food for the whole plant!)
    • Chloroplastsare tiny factories inside the cells of plants.
    • Chloroplaststake the energy from the sunlight and use it to make plant food.
    • Chlorophyll is the green color in chloroplast, which makes the leaves green. When you squeeze the kale the green liquid that comes out is the chlorophyll.
  6. Students work in small groups to make the salad dressing following these steps:
    • Add a small amount of vinegar to the larger bowl.
    • Whisk oil in gradually as you add small amounts of honey and pepper.
  7. Ask: What happens to the vinegar as you whisk in the oil?
  8. Distribute small amounts of the salad dressing into the students’ bowls. Students taste the kale salads.
3
Student Reflection
  1. What else needs light to make food? How is this different from how plants use light to make food?
Additional Information
  1. We can also see chlorophyll (or a lack thereof) when we make our compost piles. The browns, oranges, and reds of fall leaves are the colors “underneath” that are revealed after the chlorophyll (green) dies in the autumn leaves. We use these brown leaves to help make the perfect compost pile.
English Language Learning (ELL) Focus: Scientific Vocabulary
  • The chlorophyll in leaves suck upthe sunlight through the chloroplast.
  • The chloroplastis a sun-harvesting molecule.

Academic Standards

California Academic Content Standards

Health

7.2.N

Demonstrate how to prepare a healthy meal or snack using sanitary food preparation and storage practices.

Next Generation Science Standards

Disciplinary Core Ideas

LS1.A

Structure and Function: All organisms have external parts. Plants have different parts (roots, stems, leaves, flowers, fruits) that help them survive and grow. Different animals use their body parts in different ways to see, hear, grasp objects, protect themselves, move from place to place, and seek, find, and take in food, water and air.

PS3.D

Energy in Chemical Processes and Everyday Life: The energy released [from] food was once energy from the sun that was captured by plants in the chemical process that forms plant matter (from air and water).

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