Water in the root enters due to

Water is the most limiting abiotic (non-living) factor to plant growth and productivity, and a principal determinant of vegetation distributions worldwide. Since antiquity, humans have recognized plants' thirst for water as evidenced by the existence of irrigation systems at the beginning of recorded history. Water's importance to plants stems from its central role in growth and photosynthesis, and the distribution of organic and inorganic molecules. Despite this dependence, plants retain less than 5% of the water absorbed by roots for cell expansion and plant growth. The remainder passes through plants directly into the atmosphere, a process referred to as transpiration. The amount of water lost via transpiration can be incredibly high; a single irrigated corn plant growing in Kansas can use 200 L of water during a typical summer, while some large rainforest trees can use nearly 1200 L of water in a single day! If water is so important to plant growth and survival, then why would plants waste so much of it? The answer to this question lies in another process vital to plants — photosynthesis. To make sugars, plants must absorb carbon dioxide (CO 2) from the atmosphere through small pores in their leaves called stomata (Figure 1). However, when stomata open, water is lost to the atmosphere at a prolific rate relative to the small amount of CO 2 absorbed; across plant species an average of 400 water molecules are lost for each CO 2 molecule gained. The balance between transp...

Correct Option D Solution ∙ Option A We know that the water moves from the region of higher concentration to the region of lower concentration and that movement is known as diffusion. ∙ Option B W.P. or wall pressure is the pressure which is applied by the cell wall to the contents of a plant cell and it is quite similar as well as against the turgor pressure. ∙ Option C Turgor pressure is the pressure inside the cell which the cell membrane against the cell wall. This pressure is caused due to the osmotic flow of the water and it is opposite to the wall pressure. ∙ Option D Osmotic pressure is the pressure which is applied for the prevention of fluid movement through a semipermeable membrane that separates the solution from pure water. It is to prevent the movement of water from low solute concentration to high solute concentration. The root hairs absorb the water through the process of osmotic pressure. So, the correct option is D.

Diffusion is a process by which molecules intermingle as a result, of their kinetic energy of random motion. It is free movement of a substance from a region of higher concentration to lower concentration. For example, dissolving a coloured dye in water. Active transport is a transport of substance against the concentration gradient using energy/ATP. Reverse osmosis uses a method in which pressure is applied to overcome osmotic pressure. The semipermeable membrane is used in this process.

Views: 5,080 F , Cl , Br, etc., (which is placed at the extreme right side in the periodic table, excluding the inert gases) is the smallest in size, however, the size of the atom of an inert gas is bigger than that of the preceding halogen atom. The greater size of the inert gas atom (or noble gas atom) in a period is due to the structural stability of its outermost shell consisting of a octet of electrons. 4. Metallic Character Views: 5,690 H 2 ​ SO 4 ​ , HCl , HNO 3 ​ , NaCl and NaOH ? Also write the chemical equations if reaction occurs. 6. You are provided with two containers made up of copper and aluminium. You are also provided with solutions of dilute HC, dilute HNO 3 ​ , ZnCl 2 ​ and H 2 ​ O. In which of the above containers these solutions can be kept? On adding a drop of barium chloride solution to an aqueous solution of sodium sulphite, white precipitate is obtained. Views: 5,170 ( HCl ), sulphuric acid ( H 2 ​ SO 4 ​ ), nitric acid ( HNO 3 ​ ), acetic acid ( CH 3 ​ COOH ), sodium hydroxide ( NaOH ), calcium hydroxide [ Ca ( OH ) 2 ​ ], potassium hydroxide ( KOH ), magnesium hydroxide [ Mg ( OH ) 2 ​ ], and ammonium hydroxide ( NH 4 ​ OH ). (ii) Put a drop of each of the above solutions on a watch-glass and test with a drop of the following indicators. Red litmus solution, Blue litmus solution, Phenolphthalein solution, Methyl orange solution. Observation The changes observed are as follows :

Plants absorb water from the soil by means of the process of osmosis. To speed up osmosis, the root hair cells are modified by means of having a large surface area. The water absorbed is transported by means of the large roots to other parts of the plant wherein it is used for various needs. water enters into root hair cells by osmosis, since roo hair cells have low water potential gradient because of ions and organic substances.

3 Biological Macromolecules • Introduction • 3.1 Synthesis of Biological Macromolecules • 3.2 Carbohydrates • 3.3 Lipids • 3.4 Proteins • 3.5 Nucleic Acids • Key Terms • Chapter Summary • Review Questions • Critical Thinking Questions • Test Prep for AP®Courses • Science Practice Challenge Questions • 4 Cell Structure • Introduction • 4.1 Studying Cells • 4.2 Prokaryotic Cells • 4.3 Eukaryotic Cells • 4.4 The Endomembrane System and Proteins • 4.5 Cytoskeleton • 4.6 Connections between Cells and Cellular Activities • Key Terms • Chapter Summary • Review Questions • Critical Thinking Questions • Test Prep for AP®Courses • Science Practice Challenge Questions • 5 Structure and Function of Plasma Membranes • Introduction • 5.1 Components and Structure • 5.2 Passive Transport • 5.3 Active Transport • 5.4 Bulk Transport • Key Terms • Chapter Summary • Review Questions • Critical Thinking Questions • Test Prep for AP®Courses • Science Practice Challenge Questions • 6 Metabolism • Introduction • 6.1 Energy and Metabolism • 6.2 Potential, Kinetic, Free, and Activation Energy • 6.3 The Laws of Thermodynamics • 6.4 ATP: Adenosine Triphosphate • 6.5 Enzymes • Key Terms • Chapter Summary • Review Questions • Critical Thinking Questions • Test Prep for AP®Courses • Science Practice Challenge Questions • 7 Cellular Respiration • Introduction • 7.1 Energy in Living Systems • 7.2 Glycolysis • 7.3 Oxidation of Pyruvate and the Citric Acid Cycle • 7.4 Oxidative Phosphorylation • 7.5 Metabol...

Root hair cells The root hairs are where most water absorption happens. They are long and thin so they can penetrate between soil particles and they have a large surface area for absorption of water. Water passes from the soil water to the root hair cell's cytoplasm by osmosis . This happens because the soil water has a higher water potential than the root hair cell cytoplasm: Solution Water concentration Concentration of dissolved solutes Soil water High Low Root hair cell cytoplasm Low High Root hair cells - Higher To maintain the concentration gradient and so the constant movement of water into the root hair cell by osmosis, the root hair cell actively transports mineral salts into the cell. This means it uses energy - these cells are actively respiring in order to move mineral salts from low concentration outside of the cell to the high concentration in the cell. Thus ensuring osmosis and the transpiration stream continues.