1.
Where is the leaf does most photosynthesis take place?
Correct Answer
B. Palisade Layer
Explanation
The palisade layer is the correct answer because it is the main site of photosynthesis in the leaf. This layer is located right below the upper epidermis and contains closely packed, elongated cells that are rich in chloroplasts. The chloroplasts contain the pigment chlorophyll, which absorbs light energy and converts it into chemical energy through photosynthesis. The palisade layer is positioned close to the surface of the leaf to maximize light absorption, making it the primary site for photosynthesis in the leaf.
2.
What carries water up through a plant?
Correct Answer
D. Xylem Vessels
Explanation
Xylem vessels are responsible for carrying water up through a plant. These specialized cells form a network of tubes that transport water and minerals from the roots to the rest of the plant. The xylem vessels have a structure that allows for efficient water movement, including a hollow center and reinforced cell walls. Through a process called transpiration, water is pulled up through the xylem vessels by the evaporation of water from the leaves. This upward movement of water is crucial for the plant's survival, as it provides the necessary hydration and nutrients for growth and photosynthesis.
3.
What are the two products of photosynthesis?
Correct Answer
E. Glucose and oxygen
Explanation
Photosynthesis is the process by which plants convert sunlight into energy. During this process, carbon dioxide and water are combined to produce glucose and oxygen. Glucose is a sugar that serves as a source of energy for the plant, while oxygen is released as a byproduct. Therefore, the correct answer is "Glucose and oxygen."
4.
Which is not a limiting factor of photosynthesis?
Correct Answer
A. Oxygen levels
Explanation
Photosynthesis is the process by which plants convert sunlight, carbon dioxide, and water into glucose and oxygen. While oxygen is produced as a byproduct of photosynthesis, its presence or absence does not directly limit the process. The limiting factors of photosynthesis include carbon dioxide levels, chlorophyll concentration, light intensity, and temperature. These factors determine the rate at which photosynthesis can occur, but the availability of oxygen does not directly affect the process. Therefore, oxygen levels are not a limiting factor of photosynthesis.
5.
Which mineral ions are important in the manufacture of chlorophyll?
Correct Answer
E. Magnesium
Explanation
Chlorophyll is a pigment found in plants that is responsible for capturing light energy for photosynthesis. Magnesium plays a crucial role in the structure of chlorophyll molecules, as it is located at the center of the chlorophyll molecule and is involved in capturing and transferring light energy. Without magnesium, chlorophyll cannot function properly, leading to a decrease in photosynthesis and plant growth. Therefore, magnesium is an important mineral ion in the manufacture of chlorophyll.
6.
Which of the following is not correct?
Correct Answer
E. Glucose is stored as glycogen by a plant.
Explanation
Glucose is stored as glycogen by animals, not plants. Plants store glucose as starch.
7.
Iodine allows us to test the presence of what?
Correct Answer
C. Starch
Explanation
Iodine allows us to test the presence of starch. Iodine reacts with starch to form a blue-black color. This reaction is used as a common test for the presence of starch in various substances.
8.
What is the approximate concentration of carbon dioxide in the atmosphere?
Correct Answer
D. 0.04%
Explanation
The approximate concentration of carbon dioxide in the atmosphere is 0.04%. This is a relatively small percentage, but it is significant because carbon dioxide is a greenhouse gas that contributes to global warming. The increase in carbon dioxide levels due to human activities, such as burning fossil fuels, is a major concern for climate change.
9.
What is a modern way of growing crops?
Correct Answer
E. Hydroponics
Explanation
Hydroponics is a modern way of growing crops that involves cultivating plants without soil. Instead, plants are grown in a nutrient-rich water solution, allowing them to receive all the necessary nutrients directly. This method is gaining popularity due to its efficient use of water and space, as well as its ability to control and optimize growing conditions.
10.
Which is the key symptom of nitrate deficiency in a plant?
Correct Answer
A. Stunted growth
Explanation
Nitrate deficiency in plants leads to stunted growth. Nitrate is an essential nutrient for plants as it is a major component of proteins, which are necessary for growth and development. When plants lack an adequate supply of nitrate, their growth becomes restricted, resulting in stunted growth. This symptom is commonly observed in plants with nitrate deficiency and can be an indication that the plant is not receiving enough nutrients to support its growth.