Factors affecting photosynthesis
- Which of the following elements is responsible for maintaining turgor in cells ? Answer: 2. Potassium Potassium regulates osmotic potential, so it maintains turgor and opens stomata. Mg is in chlorophyll, Ca is in the mid... 1
- In which of the following forms is iron absorbed by plants ? Answer: 4. Both ferric and ferrous Plants take up iron mainly as ferric ions (Fe ³⁺ ), and it is also taken as ferrous ions (Fe ²⁺ ). Since... 1
- Stomatal movement is *not* affected by Answer: 2. O ₂ concentration Stomata respond to light, CO ₂ level, temperature and water status, but not to O ₂ concentration. Low CO ₂ and... 1
- With reference to factors affecting the rate of photosynthesis, which of the following statements is not correct ? Answer: 2. C₃ plants respond to higher temperatures with enhanced photosynthesis while C₄ plants have much lower temperature optimum The wro... 1
- A few drops of sap were collected by cutting across a plant stem by a suitable method. The sap was tested chemically. Which one of the following test results indicates that it is phloem sap? Answer: 1. Alkaline Phloem sap is rich in sugar (mainly sucrose), has a high refractive index because of dissolved solutes, and is alkaline... 1
- Water vapour comes out from the plant leaf through the stomatal opening. Through the same stomatal opening carbon dioxide diffuses into the plant during photosynthesis. Reason out the above statements using one of following options : Answer: 2. Both processes can happen together because the diffusion coefficient of water and CO ₂ is different. Both processes can occur tog... 1