FreeNotes
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
Roots absorb water and minerals through two main processes: active absorption and passive absorption. Passive absorption occurs when water moves into the root cells by osmosis. The water in the soil has a higher water potential than the root cells, so water moves from the soil into the root hair cells through the semi-permeable membrane. … Read more
The root is a complex structure composed of several layers. The outermost layer is the epidermis, which serves as a protective barrier. The epidermis is covered with tiny, hair-like extensions called root hairs, which significantly increase the surface area for water and mineral absorption from the soil. Beneath the epidermis lies the cortex, which stores … Read more
Nitrogen is a vital element for plants because it is a major component of amino acids, which are the building blocks of proteins. Proteins are essential for various physiological functions in plants, including enzyme activity, growth, and structural development. Nitrogen is absorbed by plants in the form of nitrates and ammonium ions from the soil, … Read more