Science Quiz Questions And Answers For Class 10

Photosynthesis is the process where plants convert light energy into chemical energy in the form of glucose. This energy is essential for the growth and development of plants. The correct answer is light, as it is the primary source of energy that drives the photosynthetic process. Heat and electrical energy do not play a direct role in photosynthesis, and sand is not a form of energy.

Photosynthesis is the process by which green plants, algae, and some bacteria convert sunlight, carbon dioxide, and water into glucose and oxygen. This process occurs in the chloroplasts, which are typically found in the leaves of plants. The root, on the other hand, is responsible for absorbing water and nutrients from the soil and is usually not exposed to sunlight. Therefore, photosynthesis does not take place in the root.

Carbon dioxide is needed for photosynthesis because it is fixed by plants to produce glucose and oxygen. During photosynthesis, plants use sunlight, water, and carbon dioxide to create glucose, which is their source of energy. Oxygen is also produced as a byproduct of this process. Without carbon dioxide, plants would not be able to carry out photosynthesis and produce the necessary energy for the growth and survival of the vast majority of the Earth’s organisms, which require oxygen and glucose.

Chloroplasts are the organelles found in plant cells where photosynthesis takes place. Inside the chloroplasts, chlorophyll captures solar and light energy, which is then used to convert carbon dioxide and water into glucose and oxygen through a series of chemical reactions. This process is known as photosynthesis and is essential for the plant's survival as it provides the energy needed for growth and development. Therefore, the correct location for photosynthesis is within the chloroplasts.

Photosynthesis is the process by which plants convert light energy into chemical energy in the form of glucose. This process takes place in chloroplasts, which contain the green pigment chlorophyll. Chlorophyll absorbs light energy, which is used to split water molecules into oxygen and hydrogen. The hydrogen is then combined with carbon dioxide to produce glucose.  

During photosynthesis, plants convert carbon dioxide and water into glucose and oxygen. Oxygen is released as a waste by-product and is released into the atmosphere.

The ozone layer, located in the Earth's stratosphere, plays a critical role in protecting living organisms by absorbing the majority of the sun's harmful ultraviolet (UV) radiation. Without this protective layer, UV radiation would be intense enough on Earth’s surface to cause severe damage to the DNA of plants and animals, leading to increased rates of skin cancer and cataracts in humans, and detrimental effects on aquatic ecosystems and agricultural productivity.

Increasing the carbon dioxide concentration in a greenhouse promotes faster growth of tomatoes. This suggests that the availability of carbon dioxide was a limiting factor in the growth of tomatoes. The other options, temperature and light intensity, are not mentioned in the given information and therefore cannot be inferred as limiting factors.

Chlorophyll is the correct answer because it is the green pigment found in leaf cells that is responsible for absorbing light energy for photosynthesis. It is located in the chloroplasts, which are the organelles where photosynthesis takes place. Chlorophyll is essential for plants to convert sunlight into chemical energy, allowing them to produce glucose and oxygen. Without chlorophyll, plants would not be able to carry out photosynthesis, where light is required to catalyze the reaction.

Plants need nitrate ions primarily to make proteins. Nitrate ions are a key source of nitrogen, which is an essential element for the synthesis of amino acids, the building blocks of proteins. These proteins are crucial for plant growth, development, and various metabolic processes. While nitrogen is also a component of chlorophyll, its primary role through nitrate ions is in protein synthesis.

The law of conservation of mass states that in a closed or isolated system, the total mass of the reactants before a chemical reaction must equal the total mass of the products after the reaction. This means that atoms are neither created nor destroyed during a chemical reaction, but simply rearranged to form different substances. This fundamental principle is crucial for understanding chemical reactions and balancing chemical equations.