Classroom activity 5 1. Explain why the relationship between the legumes and the plant is a mutualistic rel 2. Why do plants need nitrogen? 3. Nitrogen gas is unusable to most plants. usable by plants. 4. Explain why the relationship between 5. Explain how cows benefit from having Eutualistic relationship.

Let's break down each question step by step: ### 1. Explain why the relationship between the legumes and the plant is a mutualistic relationship. The relationship between legumes (such as beans, peas, and lentils) and certain bacteria (like Rhizobium) is mutualistic because both parties benefit from the interaction. - **Legumes**: They provide a habitat and nutrients for the bacteria. The roots of legumes form nodules where these bacteria live. - **Bacteria**: In return, the bacteria convert atmospheric nitrogen (N₂) into ammonia (NH₃) through a process called nitrogen fixation. This ammonia is then used by the legumes to synthesize proteins and other essential compounds. Thus, both the legumes and the bacteria gain benefits from this relationship: the legumes receive usable nitrogen, and the bacteria receive nutrients and a safe environment. ### 2. Why do plants need nitrogen? Plants need nitrogen for several critical reasons: - **Protein Synthesis**: Nitrogen is a key component of amino acids, which are the building blocks of proteins. Proteins are essential for plant growth and development. - **Nucleic Acids**: Nitrogen is also a vital part of nucleic acids (DNA and RNA), which are necessary for cell division and genetic information transfer. - **Chlorophyll Production**: Nitrogen is a component of chlorophyll, the molecule responsible for photosynthesis. Without sufficient nitrogen, plants cannot produce enough chlorophyll, leading to poor growth and yellowing of leaves. ### 3. Nitrogen gas is unusable to most plants. Nitrogen gas (N₂) is indeed unusable to most plants because they cannot directly utilize it in its gaseous form. Plants require nitrogen in a fixed form, such as ammonium (NH₄⁺) or nitrate (NO₃⁻), which they can absorb through their roots. - **Conversion Process**: The conversion of nitrogen gas into these usable forms is primarily carried out by nitrogen-fixing bacteria, which either live in symbiosis with plants (like legumes) or in the soil. ### 4. Explain why the relationship between cows and legumes is mutualistic. The relationship between cows and legumes can be considered mutualistic in the context of grazing and nutrient cycling: - **Cows**: When cows graze on legumes, they obtain high-quality protein and nutrients from the plants. This is beneficial for their growth and milk production. - **Legumes**: As cows consume legumes, they also contribute to the nutrient cycle. The cows excrete waste that contains nitrogen-rich compounds, which can enhance soil fertility. This, in turn, benefits the legumes and allows them to thrive. Thus, both cows and legumes benefit from this relationship: cows receive nutrition, and legumes benefit from improved soil conditions. ### 5. Explain how cows benefit from having a mutualistic relationship with certain bacteria in their stomachs. Cows have a mutualistic relationship with certain bacteria in their stomachs, particularly in the rumen, which is essential for their digestion: - **Bacteria**: These bacteria help break down complex carbohydrates (like cellulose) found in plant materials that cows consume. This process is known as fermentation. - **Cows**: In return, cows provide a suitable environment and nutrients for the bacteria to thrive. The breakdown of cellulose allows cows to extract energy and nutrients from fibrous plant material, which they would otherwise be unable to digest. This mutualistic relationship is crucial for the cow's ability to obtain energy from their herbivorous diet, leading to better health and productivity.