1.
Which gas is needed for photosynthesis?
Answer:
Carbon dioxide
Explanation:
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.
2.
What type of energy is required for photosynthesis to happen?
Answer:
Light
Explanation:
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.
3.
What is the waste by-product of photosynthesis?
Answer:
Oxygen
Explanation:
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.
4.
Tomatoes in a greenhouse grow faster if the carbon dioxide concentration is increased. Why is that?
Answer:
Carbon dioxide concentration must have been a limiting factor earlier.
Explanation:
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.
5.
What is the equation of photosynthesis?
Answer:
Carbon dioxide + water → glucose + oxygen
Explanation:
The correct answer is "carbon dioxide + water → glucose + oxygen." This equation represents the process of photosynthesis, where carbon dioxide and water are converted into glucose (a form of sugar) and oxygen. During photosynthesis, plants use sunlight as an energy source to convert carbon dioxide and water into glucose, which they can use for energy, and oxygen, which is released into the atmosphere.
6.
Why do plants need nitrate ions?
Answer:
To make proteins
Explanation:
Plants need nitrate ions to make proteins. Nitrate ions are a vital source of nitrogen, which is an essential element for amino acids, the building blocks of proteins. Proteins are crucial for various plant functions, including growth and defense against pathogens. Nitrate ions are absorbed by plant roots and transported to different parts of the plant, where they are used to form amino acids. These amino acids are then assembled into various types of proteins, which play a crucial role in the structure and function of plant cells and tissues.
7.
What is the substance that makes leaves look green?
Answer:
Chlorophyll
Explanation:
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.
8.
Where does photosynthesis takes place in?
Answer:
Chloroplasts
Explanation:
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.
9.
What is the primary function of the ozone layer in the Earth's atmosphere?
Answer:
To absorb and scatter solar ultraviolet light
Explanation:
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.
10.
What is the law of conservation of mass in a chemical reaction?
Answer:
Matter is neither created nor destroyed, only transformed.
Explanation:
The law of conservation of mass, stated by Antoine Lavoisier in the 18th century, is a fundamental concept in chemistry that applies to all chemical reactions. It asserts that the mass of the reactants in a chemical process must equal the mass of the products. This law implies that during a chemical reaction, atoms are neither created nor destroyed; they are merely rearranged to form new substances. This principle is crucial for chemists to balance chemical equations accurately.
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