1. Cell division gives rise to cells that eventually lose their ability to divide and undergo re-differentiation, specializing in specific functions. 2. An example of re-differentiation occurs during the formation of secondary xylem and phloem in the vascular cambium.
1. Differentiation is the mechanism through which cell types acquire unique forms and functions. 2. Stem cells utilize differentiation to transform into specialized cell types with specific roles. 3. This crucial process is fundamental for the development of diverse organs in multicellular organisms. 4. The differentiation of cells ensures the creation of distinct and functional … Read more
i. The examination of plant ash reveals the absorption of minerals by plants from the soil and their surroundings. ii. Plants absorb minerals primarily in the ionic (dissolved) form through their roots, and subsequently, these minerals are transported within the plant. iii. The absorption of mineral ions operates independently of water absorption. iv. Mineral ion … Read more
1. Macronutrients, such as carbon (C), hydrogen (H), oxygen (O), nitrogen (N), sulfur (S), magnesium (Mg), calcium (Ca), potassium (K), etc., are essential minerals needed in significant quantities for plant metabolism. 2. Micronutrients, including copper (Cu), cobalt (Co), manganese (Mn), boron (B), zinc (Zn), chlorine (Cl), etc., are minerals needed in small quantities for essential … Read more
A) Osmotic pressure is the minimum pressure needed to prevent the inward flow of a pure solvent through a semipermeable membrane. Turgor pressure, inside the cell, pushes the plasma membrane against the plant cell wall. Turgor Pressure vs. Osmotic Pressure: Turgor Pressure 1. Turgor pressure arises in the cell due to osmotic water entry, maintaining … Read more
(i) Osmosis is a specific type of solvent diffusion through a semipermeable membrane. (ii) It involves the movement of ions, atoms, or molecules from areas of higher concentration to regions of lower concentration. (iii) When a living cell undergoes exo-osmosis in a hypertonic solution, it experiences plasmolysis. (iv) The swelling of hydrophilic colloids due to … Read more
1. Water absorption in root hairs occurs through a process involving imbibition, followed by diffusion and osmosis. 2. As water enters the root hair cell, it undergoes an increase in turgor pressure, resulting in turgidity. 3. The root hair cell possesses lower solute concentration (D.ED.) compared to the adjacent cortical cell with higher solute concentration … Read more
A ‘necessary evil’ as termed by curtis transpiration because: 1. Stomata, small openings in the leaf epidermis, facilitate 90–93% of transpiration, a vital plant process. 2. To enable gaseous exchange through diffusion, stomata must remain open during this essential biological activity. 3. Gaseous exchange is crucial for both respiration and photosynthesis within plants. 4. The … Read more
Capillarity theory of water translocation: 1. Bohem proposed the capillarity theory of water translocation.Capillarity arises from the interplay of surface tension, cohesive forces, and adhesive forces among water molecules. 2. Xylem vessels and tracheids are tubular elements characterized by their luminal structure. 3. Within these elements, a water column is sustained through the synergistic influence … Read more
Significance of transpiration: 1. Facilitating a cooling effect by absorbing plant heat and converting water into vapor during transpiration. 2. Ensuring optimal turgor pressure by absorbing excess water during transpiration, promoting healthy growth. 3. Assisting mineral transport by generating a transpiration pull, aiding the roots in absorbing and distributing soil minerals. 4. Supporting water transport … Read more