GO IN DEPTH

Ocean Sunlight Discussion Questions

Ocean Sunlight Discussion Questions

Introduction

To begin this lesson, read Ocean Sunlight: How Tiny Plants Feed the Seas through once to the students. Have the students break out into small groups of four to five students. Each group should have a copy of the book so they can follow along as you read. Hold the book up to the class as you read.

Then read through the book again. This time, as you read, pause to ask the questions listed and point to the illustrations in the book. The illustrations create a visual explanation of photosynthesis and will further student understanding of the concepts covered in this lesson.


Read the first two pages. Pause to ask students:

  • Who is “me” in this story?
      (The sun.)
  • What do you think all the little yellow dots represent?
      (They are the sun’s energy.)

Read the next two pages.

  • What do you think these boxes represent?
      (The first box is water; the second is carbon dioxide; the third is sugar; the last is oxygen.)
  • What are the authors trying to explain in these illustrations?
      (Plants absorb the sunshine. Their leaves breathe in carbon dioxide and their roots suck up water. The sun’s energy helps the plant split the water and CO₂ molecules into hydrogen and oxygen. Then the plants breathe out this oxygen into the air so that we humans have oxygen to breathe.)

Read the next two pages.

  • What’s happening on these pages?
      (The boy gets energy from eating the plant [apple]. His body uses the energy [sugar] from the plant to live. Because he is alive, he breathes in oxygen and breathes out carbon dioxide. The plants breathe in his carbon dioxide and the cycle starts all over again.)
  • What do you see happening with the animals in the picture?
      (The mice eat the plants, the snake eats the mice, the raccoon eats the snake, and the cat eats the raccoon.)
  • What do you think all this eating, breathing, and eating each other is called?
      (The chain of life or the food chain.)

Read the next two pages.

  • What’s happening on these pages?
      (Lots of different fish are eating other fish.)

Read the next two pages.

  • What do you see on these pages?
      (Fish are eating the plants at the surface of the water, but deep in the ocean, the fish are eating other fish.)

Read the next two pages.

  • What do you think the authors mean by an invisible pasture of the sea?
      (That the plants in the sea are so tiny you can only see them with a microscope.)
  • What are these plants called?
      (They are called phytoplankton.)
  • What do these pictures tell you about phytoplankton?
      (They come in many different sizes and shapes, and they are everywhere in the ocean.)

Read the next two pages.

  • What percentage of the oxygen we breathe comes from land?
      (50%)
  • What percentage comes from the sea?
      (50%)
  • If half of the oxygen comes from the ocean and half from land, what does this tell us about the air we breathe?
      (All the oxygen in the air comes from plant life.)

Read the next three pages. Then turn back to the previous pages and ask the students:

  • So what’s going on here? What do the authors mean by day 1, day 3, day 5, etc.?
      (They mean that every phytoplankton can double its size in about one day.)
  • What happens to all these tiny phytoplankton?
      (They get eaten up by other sea life.)

Now turn the page, read the page on the right. Read this page slowly so students can absorb what they are hearing.

  • What do you see happening here?
      (Zooplankton are eating phytoplankton.)
  • What do you think the difference is between phytoplankton and zooplankton?
      (Phytoplankton are tiny plants and zooplankton are tiny animals. But unlike other life on earth that has many cells, most plankton has only one cell each.)
  • Why isn’t the ocean completely full of phytoplankton if it multiplies itself every day?
      (The zooplankton eats it so there are always about the same number of phytoplankton.)
  • What happens to the zooplankton? If zooplankton eats phytoplankton, why isn’t the ocean full of zooplankton?
      (Because bigger animals are eating the zooplankton too.)

Read the next two pages.

  • What do you see happening on these pages?
      (The bigger fish are eating the smaller fish, and a bird is eating a fish.)
  • What’s the definition of the chain of life?
      (We are all connected, and we all depend on each other to live and eat and breathe.)
  • Wait! What’s a bird doing in this picture?
      (It’s eating a fish.)
  • How is the bird part of the chain of life? It doesn’t live in the ocean.
      (The bird eats the fish and becomes food for other animals, so the animal that eats the bird on land, is also eating phytoplankton.)

Read the next four pages.

  • Look closely at the pictures of sea creatures in the boxes. What do you see?
      (Some sea creatures have lights on their bodies. Some of them are eating other creatures.)
  • Why do you think they have lights as part of their bodies?
      (Because it’s dark and they need to see the food so they can eat it.)
  • The authors tell us that animals look for phytoplankton in different places. They tell us that some animals wait instead of looking for phytoplankton. Let’s see what they might be waiting for. (Turn page.)

Read the next two pages.

  • What is marine snow?
      (It’s dead animals, phytoplankton, and their byproducts.)
  • What else is marine snow?
      (It’s nutritious food for marine life.)
  • What do we mean by nutritious food?
      (It’s food that has good things for our bodies. It’s not junk food.)

Read the next two pages.

  • Where do you think this nutritious food originally comes from?
      (The sun. The phytoplankton get their nutrition, or energy, from the sun. They need the sun to grow and be food for all the sea animals.)
  • The authors tell us that phytoplankton also need marine snow to grow. How do you think the phytoplankton find the marine snow if they live on the surface of the sea and the marine snow is in the dark waters below?
      (Students' answers may vary. Encourage them to explain their answers.)
    Let’s find out!

Read the next four pages.

  • How do you think this nutritious marine snow gets to the ocean surface so the phytoplankton can eat it?
      (The sun creates wind and the wind creates waves in the ocean. The waves stir up the water so that the marine snow feeds the phytoplankton on the ocean surface.)
  • How does this picture illustrate the chain of life?
      (The whales are eating the smaller fish, which eat the smaller fish, which eat even smaller fish, which eat the phytoplankton.)

Read the last two pages of the story.

  • What does this picture tell you?
      (That the chain of life is on the land AND in the sea, and that all living things are connected.)
This teacher sheet is a part of the Ocean Sunlight: How Tiny Plants Feed the Seas lesson.

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