Leaf Structure and Function

Question 7:(a) What is meant by compensation point?(b) How does the compensation point affect the production and usage of oxygen and carbon dioxide? Answer:(a) The compensation point is the level of light intensity when the rate of respiration equals to the rate of photosynthesis.(b)At the compensation point, the amount of oxygen produced is enough for … Read more

Question 4:Figure 1.1 and Figure 1.2 show the average of stomata size in two different types of plants in a 24-hour duration. One of the plants is placed in a humid surrounding whereas another plant is placed in a hot and dry surrounding.(a) Which graph shows the plant that has been placed in a hot … Read more

Question 1:(a) Petiole and lamina are external structures of a leaf. State the function of these two structures.(b) A leaf is a plant organ that is flat, thin and green in colour. Explain the importance of these characteristics on the function of a leaf. Answer:(a) Petiole is the leaf stalk that connects lamina to the … Read more

Question 1:Give the definition of compensation point. Answer:Compensation point is the level of light intensity when the rate of respiration equals to the rate of photosynthesis. Question 2:The compensation point of fern plants which grow on the rainforest floor happens at 10.00 am. In your opinion, at what time does a ficus plant which grows … Read more

Question 1:State three main factors affecting the rate of photosynthesis. Answer:Light intensity, temperature and carbon dioxide concentration Question 2:State the effects of different light intensities on the rate of photosynthesis. Answer:At low light intensities, the stomata will close and lower the rate of photosynthesis. At high light intensities, the stomata will open and until it … Read more

Question 1:What is the meaning of transpiration?State the relationship between transpiration and stomata. Answer:Transpiration is a process of water loss in the form of water vapour through evaporation from the plants to the atmosphere. Transpiration occurs in stomatal pore. Question 2:Other than higher temperature and faster air movement, light intensity also affects the rate of … Read more

Question 1:State the differences of gaseous exchange in plants during respiration and photosynthesis. Answer:Respiration – Oxygen is absorbed and carbon dioxide is releasedPhotosynthesis – Carbon dioxide is absorbed and oxygen is released Question 2:How does humidity in the surroundings affect the size of the stomatal opening? Answer:The humid surroundings causes the size of the stoma … Read more

Question 1:Name two external structures of a leaf. Answer:Lamina and petiole Question 2:What is the importance of cuticle in leaves? Answer:To prevent excessive loss of water through evaporation. Question 3:Name five internal structures of a leaf. Answer:Upper epidermis, palisade mesophyll, spongy mesophyll, vascular bundle and lower epidermis. Question 4:State the functions of xylem and phloem. … Read more