Energy in Ecosystems — Answer Key
Part A: Fix the Sentence
Each sentence has an error. Rewrite it correctly on the line.
1. Fix the sentence:
In Grade 5 science, plants makes sugar using sunlight.
Corrected: In Grade 5 science, plants make sugar using sunlight.
A plural noun like 'plants' uses the plural verb form 'make' in Grade 5 science writing.
2. Fix the sentence:
Photosynthesis need sunlight, water, and carbon dioxide.
Corrected: Photosynthesis needs sunlight, water, and carbon dioxide.
Singular subjects in Grade 5 science take singular verbs ending in -s, so 'needs' is correct.
3. Fix the sentence:
The leaf release oxygen into the air during the day.
Corrected: The leaf releases oxygen into the air during the day.
In Grade 5 science, a singular subject 'leaf' pairs with the singular verb 'releases'.
Part B: Fill in the Blank
Write the missing word or number on each line.
1. In Grade 5 science, plants use energy from the sun to power photosynthesis.
Light energy from the sun drives the photosynthesis reaction in Grade 5 ecosystems.
2. During photosynthesis, plants take in carbon dioxide from the air.
Plants pull carbon dioxide through their leaves to combine with water in Grade 5 science.
3. Plants pull water up from the soil through their roots.
Water is one of the two raw materials, with CO2, that plants need for Grade 5 photosynthesis.
4. Photosynthesis releases oxygen gas that animals breathe.
Oxygen is the by-product of photosynthesis and supports animal life across Grade 5 ecosystems.
Part C: Short Answer
Answer each question in one or two complete sentences.
1. In Grade 5 science, why is the sun called the start of the photosynthesis equation?
Sample answer: The sun is the start because its light energy lets plants combine water and carbon dioxide into sugar; without sunlight, photosynthesis cannot happen.
Sunlight supplies the energy that drives the chemical change from CO2 and water into sugar and oxygen.
2. Name the two products plants make during photosynthesis.
Sample answer: Plants make sugar (glucose), which stores food energy, and oxygen, which is released into the air for animals to breathe.
Sugar feeds the plant and animals that eat it, while oxygen supports breathing organisms in the ecosystem.