Photosynthesis Vocabulary worksheet - Free Printable

To solve this problem, we need to match each vocabulary word on the left with its correct definition on the right. The definitions are currently mixed up. Let’s go step by step and pair them correctly based on what we know about photosynthesis.

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Step 1: Understand each term

Let’s list the terms and think about what they mean:

- Photosynthesis → The whole process plants use to make food using sunlight.
- Chemical reaction → When substances change into new substances.
- Reactant → What you start with in a chemical reaction (like ingredients).
- Product → What you end up with after a chemical reaction.
- Autotroph → An organism that makes its own food (like plants).
- Light (solar) energy → Energy from the sun.
- Chemical energy → Energy stored in chemicals, like in glucose or ATP.
- Stoma → Tiny holes in leaves for gas exchange.
- Chloroplast → Organelle in plant cells where photosynthesis happens; contains chlorophyll.
- Chlorophyll → Green pigment that captures sunlight.
- Carbon dioxide → Gas plants take in from air for photosynthesis.
- Water → Liquid H₂O, also used in photosynthesis.
- Glucose → Sugar made during photosynthesis — it’s food for the plant.
- Oxygen → Gas released as a product of photosynthesis.
- Adenosine triphosphate (ATP) → Energy carrier molecule in cells.

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Step 2: Match each term to its correct definition

Now let’s go through the definitions given and assign them properly.

Original table has mismatched pairs. We’ll fix them.

Here are the definitions provided (in order):

1. “A heavy odorless, colorless gas formed during respiration and by the decomposition of organic substances; absorbed from the air by plants in photosynthesis.”
→ This is Carbon dioxide.

2. “A chemical substance present at the start of a process.”
→ This is Reactant.

3. “A plant organelle that contains chlorophyll and other pigments.”
→ This is Chloroplast.

4. “An opening in a leaf or stem through which gases and water vapor can pass.”
→ This is Stoma.

5. “A monosaccharide sugar that has several forms.”
→ This is Glucose.

6. “When a substance changes into another substance.”
→ This is Chemical reaction.

7. “A series of chemical reactions that use the energy of sunlight to convert water and carbon dioxide into sugar and oxygen.”
→ This is Photosynthesis.

8. “A green pigment found in the chloroplast of photosynthetic organisms.”
→ This is Chlorophyll.

9. “A chemical substance that is created by some process.”
→ This is Product.

10. “Energy from the sun.”
→ This is Light (solar) energy.

11. “A liquid compound made of two parts hydrogen and one part oxygen.”
→ This is Water.

12. “The major source of energy for cellular reactions.”
→ This is Chemical energy (often referring to ATP or glucose).

Wait — actually, let’s check: “The major source of energy for cellular reactions” — that’s usually ATP, but sometimes people say glucose. But looking ahead…

13. “An organism capable of making its own food.”
→ This is Autotroph.

14. “That part of the energy in a substance that can be released by a chemical reaction.”
→ Again, this sounds like Chemical energy.

Hmm — there’s overlap. Let’s clarify.

Actually, let’s reassign carefully.

Let me write out the correct matching:

| Term | Correct Definition |
|-----------------------|------------------------------------------------------------------------------------|
| Photosynthesis | A series of chemical reactions that use the energy of sunlight to convert water and carbon dioxide into sugar and oxygen. |
| Chemical reaction | When a substance changes into another substance. |
| Reactant | A chemical substance present at the start of a process. |
| Product | A chemical substance that is created by some process. |
| Autotroph | An organism capable of making its own food. |
| Light (solar) energy | Energy from the sun. |
| Chemical energy | That part of the energy in a substance that can be released by a chemical reaction. OR “The major source of energy for cellular reactions” — both could fit, but let’s see context. Actually, ATP is more specific for “major source for cellular reactions”. Wait — let’s hold off. |
| Stoma | An opening in a leaf or stem through which gases and water vapor can pass. |
| Chloroplast | A plant organelle that contains chlorophyll and other pigments. |
| Chlorophyll | A green pigment found in the chloroplast of photosynthetic organisms. |
| Carbon dioxide | A heavy odorless, colorless gas... absorbed from the air by plants in photosynthesis. |
| Water | A liquid compound made of two parts hydrogen and one part oxygen. |
| Glucose | A monosaccharide sugar that has several forms. |
| Oxygen | A colorless, odorless gas that is essential for respiration. |
| Adenosine triphosphate (ATP) | The major source of energy for cellular reactions. |

Ah! Now it clicks.

So:

- “The major source of energy for cellular reactions” → ATP
- “That part of the energy in a substance that can be released by a chemical reaction” → Chemical energy

Also:

- “A colorless, odorless gas that is essential for respiration” → Oxygen

And:

- “A heavy odorless, colorless gas... absorbed from the air by plants...” → Carbon dioxide

Perfect.

Now let’s build the corrected table.

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Correct Matching:

Term → Definition

- Photosynthesis → A series of chemical reactions that use the energy of sunlight to convert water and carbon dioxide into sugar and oxygen.
- Chemical reaction → When a substance changes into another substance.
- Reactant → A chemical substance present at the start of a process.
- Product → A chemical substance that is created by some process.
- Autotroph → An organism capable of making its own food.
- Light (solar) energy → Energy from the sun.
- Chemical energy → That part of the energy in a substance that can be released by a chemical reaction.
- Stoma → An opening in a leaf or stem through which gases and water vapor can pass.
- Chloroplast → A plant organelle that contains chlorophyll and other pigments.
- Chlorophyll → A green pigment found in the chloroplast of photosynthetic organisms.
- Carbon dioxide → A heavy odorless, colorless gas formed during respiration and by the decomposition of organic substances; absorbed from the air by plants in photosynthesis.
- Water → A liquid compound made of two parts hydrogen and one part oxygen.
- Glucose → A monosaccharide sugar that has several forms.
- Oxygen → A colorless, odorless gas that is essential for respiration.
- Adenosine triphosphate (ATP) → The major source of energy for cellular reactions.

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This matches all terms correctly.

Final Answer:

Photosynthesis → A series of chemical reactions that use the energy of sunlight to convert water and carbon dioxide into sugar and oxygen.
Chemical reaction → When a substance changes into another substance.
Reactant → A chemical substance present at the start of a process.
Product → A chemical substance that is created by some process.
Autotroph → An organism capable of making its own food.
Light (solar) energy → Energy from the sun.
Chemical energy → That part of the energy in a substance that can be released by a chemical reaction.
Stoma → An opening in a leaf or stem through which gases and water vapor can pass.
Chloroplast → A plant organelle that contains chlorophyll and other pigments.
Chlorophyll → A green pigment found in the chloroplast of photosynthetic organisms.
Carbon dioxide → A heavy odorless, colorless gas formed during respiration and by the decomposition of organic substances; absorbed from the air by plants in photosynthesis.
Water → A liquid compound made of two parts hydrogen and one part oxygen.
Glucose → A monosaccharide sugar that has several forms.
Oxygen → A colorless, odorless gas that is essential for respiration.
Adenosine triphosphate (ATP) → The major source of energy for cellular reactions.