Review The Green Machine and The Powerhouse

​Science Probe

Ethan and his friends set out on a sunny afternoon hike through Prince William Forest Park, eager to explore the trails and enjoy the fresh air. As they wander deeper into the woods, they stumbled upon a quiet pond nestled among the trees. Curious, the group decided to investigate the water, hoping to spot a school of fish or maybe even some macroinvertebrates.

Kneeling by the edge, Ethan peers into the still water. He scans the surface and the muddy bottom, but something doesn’t look right. Ethan notices there were only a few organisms living in the pond. 

He turns to his friends and says, “I hardly see anything alive in this pond.” The group exchanges puzzled looks, wondering what might be affecting the pond’s ecosystem. 

They brainstorm ways to improve the long-term health of the ecosystem. 

Ethan: Remove all of the aquatic plants. This will raise carbon dioxide levels. Fish and insects need carbon dioxide to perform cellular respiration. 

Lilly: Plant some aquatic plants. These underwater plants will increase the available food supply and boost oxygen levels, creating a healthier environment that can support more fish and aquatic insects. 

Maddie: We should add more fish to the pond. That way, there will be more animals living in it, and it will seem healthier. 

Multiple Choice

Ethan and his friends notice that there is very little life in the pond, and wonder what might be affecting the pond’s ecosystem.  They brainstorm ways to improve the long-term health of the ecosystem. Who has the best solution?

• Ethan

• Lilly

• Maddie

Let's analyze the students' ideas.

Ethan's idea is not good, because...

• Removing plants will remove the foundation of the food web.

• There will not be producers for primary consumers.

• Remvong plants will also eliminate the production of oxygen that insects, fish and other animals need for cellular respiration.

Lilly's idea is great, beacuse...

• Adding more aquatic plants will increase the available food supply for primary consumers.

• Additional plants will also increase oxygen levels, which insects, fish and other animals need for cellular respiration.

Maddie's idea will not work, because...

• Adding fish to the pond is a very short-term solution.

• The fish will eventually die from low oxygen levels if there are not enough plants.

​Chloroplast

• organelles found in plant cells (and algae)

• conduct photosynthesis, converting light energy into chemical energy stored in glucose

• responsible for the green color of plants due to the pigment chlorophyll

​Mitochondria

• found in plant and animal cells

• generate ATP (energy) through cellular respiration

  • ATP is used by cells to power nearly all biological processes

​Compare and Contrast: Place a checkmark in the correct box. Identify each of the following as a characteristic of cellular respiration, photosynthesis, or both. (Place a checkmark in both boxes if the statement applies to both processes.) 

Multiple Choice

uses oxygen

• photosynthesis

• cellular respiration

Multiple Choice

performed primarily by plants

• photosynthesis

• cellular respiration

Multiple Choice

creates food for the cell

• photosynthesis

• cellular respiration

Multiple Choice

performed by plants and animals

• photosynthesis

• cellular respiration

Multiple Choice

takes place in mitochondria 

• photosynthesis

• cellular respiration

Multiple Choice

makes oxygen

• photosynthesis

• cellular respiration

Multiple Choice

produces carbon dioxide

• photosynthesis

• cellular respiration

Multiple Select

converts energy

• photosynthesis

• cellular respiration

Multiple Choice

requires sunlight

• photosynthesis

• cellular respiration

Multiple Choice

takes place in the chloroplast

• photosynthesis

• cellular respiration

​Data Analysis

We watched a video in which Big Manny explored the impact of light intensity on the rate of photosynthesis by placing an aquatic plant, Elodea, near a light source for high intensity and then farther away for lower intensity. He counted the number of oxygen bubbles released in each position to measure how the light affects the plant’s photosynthetic activity.

The next slide provides the complete data from his investigation. Compare your prediction of the data for 20 Watt lightbulb to the data table.

Rate of Photosynthesis and Light Intensity

​Research Question: How does light intensity influence the rate of photosynthesis in Elodea leaves?

Poll

Is your data similar to the data on the last slide?

• Yes

• No

Multiple Choice

What trend do you observe in the data table?

• Photosynthesis rate increases with increasing light intensity.

• Photosynthesis rate decreases with increasing light intensity.

• Photosynthesis rate is not affected by light intensity.

Multiple Choice

How do trees obtain energy?

• they produce food through photoynthesis

• they eat grass

• they absorb nutrients from decomposing plants and animals

• they eat animals

Multiple Select

What are the products of cellular respiration? Choose 3.

• water

• ATP

• oxygen

• sunlight

• carbon dioxide

Multiple Choice

What gas is released into the air during photosynthesis?

• oxygen

• carbon dioxide

• water

• glucose