Photosynthesis & Cellular Respiration Worksheet Answers Key

8 min read 11-15-2024

Photosynthesis & Cellular Respiration Worksheet Answers Key

Photosynthesis and cellular respiration are two fundamental biological processes that allow living organisms to convert energy from one form to another. Understanding these processes is vital for students learning about life sciences. This article serves as a comprehensive guide to photosynthesis and cellular respiration, including key concepts, differences, and an answer key for a hypothetical worksheet.

What is Photosynthesis? 🌱

Photosynthesis is the process by which green plants, algae, and some bacteria convert light energy into chemical energy, specifically glucose, using carbon dioxide and water. This process takes place primarily in the chloroplasts of plant cells.

The Photosynthesis Equation

The overall equation for photosynthesis can be simplified as follows:

[ \text{6 CO}_2 + \text{6 H}_2\text{O} + \text{light energy} \rightarrow \text{C}6\text{H}{12}\text{O}_6 + \text{6 O}_2 ]

Where:

( \text{CO}_2 ) = Carbon dioxide
( \text{H}_2\text{O} ) = Water
( \text{C}6\text{H}{12}\text{O}_6 ) = Glucose
( \text{O}_2 ) = Oxygen

Key Stages of Photosynthesis

Light-dependent Reactions: Occur in the thylakoid membranes where sunlight is absorbed and converted into ATP and NADPH.
Light-independent Reactions (Calvin Cycle): Occur in the stroma and use ATP and NADPH to convert carbon dioxide into glucose.

Importance of Photosynthesis

Oxygen Production: Photosynthesis produces oxygen as a byproduct, essential for the respiration of most living organisms.
Food Source: It is the primary source of food for nearly all life on Earth, creating the base of the food chain.

What is Cellular Respiration? 🔋

Cellular respiration is the process by which organisms convert the biochemical energy from nutrients into ATP (adenosine triphosphate), releasing waste products. This process occurs in the mitochondria of cells.

The Cellular Respiration Equation

The overall equation for cellular respiration can be expressed as:

[ \text{C}6\text{H}{12}\text{O}_6 + \text{6 O}_2 \rightarrow \text{6 CO}_2 + \text{6 H}_2\text{O} + \text{ATP} ]

Where:

( \text{C}6\text{H}{12}\text{O}_6 ) = Glucose
( \text{O}_2 ) = Oxygen
( \text{CO}_2 ) = Carbon dioxide
( \text{H}_2\text{O} ) = Water
ATP = Energy currency of the cell

Key Stages of Cellular Respiration

Glycolysis: Occurs in the cytoplasm, breaking down glucose into pyruvate, producing a small amount of ATP.
Krebs Cycle: Takes place in the mitochondria, further breaks down pyruvate, producing electron carriers (NADH and FADH2).
Electron Transport Chain: Utilizes electron carriers to produce large amounts of ATP through oxidative phosphorylation.

Importance of Cellular Respiration

Energy Production: It provides the energy needed for cellular functions.
Waste Removal: Produces carbon dioxide and water as waste products that are exhaled or excreted.

Comparing Photosynthesis and Cellular Respiration

The two processes are interconnected, with photosynthesis producing the oxygen and glucose needed for cellular respiration. Below is a table summarizing the key differences between the two processes:

<table> <tr> <th>Aspect</th> <th>Photosynthesis</th> <th>Cellular Respiration</th> </tr> <tr> <td>Purpose</td> <td>Convert light energy to chemical energy</td> <td>Convert chemical energy to usable energy (ATP)</td> </tr> <tr> <td>Location</td> <td>Chloroplasts (in plants)</td> <td>Mitochondria (in animals and plants)</td> </tr> <tr> <td>Input</td> <td>Carbon dioxide, water, and sunlight</td> <td>Glucose and oxygen</td> </tr> <tr> <td>Output</td> <td>Glucose and oxygen</td> <td>Carbon dioxide, water, and ATP</td> </tr> <tr> <td>Type of Process</td> <td>Endothermic (requires energy)</td> <td>Exothermic (releases energy)</td> </tr> </table>