FreeNotes
Active transport in plants is the process by which cells use energy (ATP) to move substances, such as minerals and ions, against their concentration gradient. In the roots, active transport allows the plant to absorb essential nutrients like potassium, nitrate, and phosphate from the soil, even when these substances are present in lower concentrations in … Read more
Phloem is responsible for transporting the products of photosynthesis, primarily sugars like sucrose, from the leaves (the source) to other parts of the plant (the sinks), such as roots and fruits. This process is known as translocation and involves the movement of sap through the phloem, driven by pressure differences. Related Questions: Why is transpiration … Read more
Osmosis is the movement of water molecules through a selectively permeable membrane from an area of low solute concentration to an area of high solute concentration. Diffusion, on the other hand, is the movement of particles from an area of high concentration to an area of low concentration. While osmosis involves only water, diffusion can … Read more
The rate of transpiration is influenced by factors such as temperature, humidity, wind speed, and light intensity. Higher temperatures and wind speeds increase the rate of transpiration, while higher humidity decreases it. The stomatal opening also plays a significant role, as more open stomata increase water loss. Related Questions: Why is transpiration called a necessary … Read more
Guard cells are specialized cells that surround stomata and control their opening and closing. When guard cells take up water, they swell, causing the stomata to open. This allows the exchange of gases, such as carbon dioxide for photosynthesis and oxygen release. When guard cells lose water, they shrink, causing the stomata to close, reducing … Read more
Osmotic adjustment in plants is a mechanism by which plants regulate their internal water balance in response to environmental stresses such as drought, salinity, or temperature fluctuations. This process involves adjusting the concentration of solutes (such as sugars, amino acids, and ions) in plant cells to help maintain a balance between water uptake and loss. … Read more
Gaseous exchange in plants occurs mainly through the stomata, tiny pores on the surface of leaves and other aerial parts of the plant. During the day, photosynthesis takes place, and plants absorb carbon dioxide (CO₂) from the atmosphere and release oxygen (O₂) as a byproduct. Oxygen is a waste product of photosynthesis, and its release … Read more
The pressure flow mechanism, also known as the mass flow hypothesis, describes the process by which food (mainly sucrose) is transported through the phloem from source tissues (e.g., leaves) to sink tissues (e.g., roots, fruits, and flowers). At the source, sucrose is actively transported into the sieve tubes of the phloem, which lowers the water … Read more
Several environmental factors influence the rate of transpiration in plants: Temperature: Higher temperatures cause the molecules of water in the plant to gain more energy, which increases the rate of evaporation. Additionally, higher temperatures cause stomata to open wider, allowing more water vapor to escape. As temperature increases, the surrounding air can hold more water … Read more
Transpiration is the process by which plants lose water vapor to the atmosphere through small pores called stomata that are located primarily on the leaves, although some are also present on stems and flowers. This loss of water vapor helps maintain a transpiration pull that facilitates the movement of water and dissolved minerals from the … Read more