TAILIEUCHUNG - Plant physiology - Chapter 3 Water and Plant Cells

WATER PLAYS A CRUCIAL ROLE in the life of the plant. For every gram of organic matter made by the plant, approximately 500 g of water is absorbed by the roots, transported through the plant body and lost to the atmosphere. Even slight imbalances in this flow of water can cause water deficits and severe malfunctioning of many cellular processes. Thus, every plant must delicately balance its uptake and loss of water. This balancing is a serious challenge for land plants. To carry on photosynthesis, they need to draw carbon dioxide from the atmosphere, but doing so exposes them to. | UNIT Transport and Translocation of water and Solutes Chapter Water and Plant Cells WATER PLAYS A CRUCIAL ROLE in the life of the plant. For every gram of organic matter made by the plant approximately 500 g of water is absorbed by the roots transported through the plant body and lost to the atmosphere. Even slight imbalances in this flow of water can cause water deficits and severe malfunctioning of many cellular processes. Thus every plant must delicately balance its uptake and loss of water. This balancing is a serious challenge for land plants. To carry on photosynthesis they need to draw carbon dioxide from the atmosphere but doing so exposes them to water loss and the threat of dehydration. A major difference between plant and animal cells that affects virtually all aspects of their relation with water is the existence in plants of the cell wall. Cell walls allow plant cells to build up large internal hydrostatic pressures called turgor pressure which are a result of their normal water balance. Turgor pressure is essential for many physiological processes including cell enlargement gas exchange in the leaves transport in the phloem and various transport processes across membranes. Turgor pressure also contributes to the rigidity and mechanical stability of nonlignified plant tissues. In this chapter we will consider how water moves into and out of plant cells emphasizing the molecular properties of water and the physical forces that influence water movement at the cell level. But first we will describe the major functions of water in plant life. WATER IN PLANT LIFE Water makes up most of the mass of plant cells as we can readily appreciate if we look at microscopic sections of mature plant cells Each cell contains a large water-filled vacuole. In such cells the cytoplasm makes up only 5 to 10 of the cell volume the remainder is vacuole. Water typically constitutes 80 to 95 of the mass of growing plant tissues. Common vegetables such as carrots and lettuce may

• Sinh học
• Mineral Nutrition
• Plant Cells
• Energy
• Enzymes
• Water Balance
• Plants
• Translocation
• Water and Solutes
• Mineral nutrients
• Root growth
• Root development
• Root growth of crop plants
• Role of mineral nutrition
• Genomic status
• Chemical and mineral composition
• Human nutrition
• Mineral composition
• Genomic groups grown in India
• Turkish Journal of Agriculture and Forestry
• Tạp chí Nông Lâm nghiệp
• Chromium toxicity in plants
• Chromosomal behavior
• Mineral nutrient status
• Plant growth and nutrition
• Root Absorption
• Soil Fungi
• Plant Interaction
• Plant Soil
• Microorganism Interactions
• Microorganism Interaction
• Abiotic Stress
• Phytoremediation
• Biofortification
• Nanoparticles
• Plant Antioxidative
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• cách trình bày báo cáo
• báo cáo lâm nghiệp
• công trình nghiên cứu lâm nghiệp
• tài liệu về lâm nghiệp