water - 副本.ppt

演讲：徐丹 单词：刘晓彬 回答：童莉 ppt：张敏敏 Water water as a percentage of body weight水作为身体重量的百分比 functions of water special characteristics of water水的特殊特性 Water is of vital importance to the body and constitutes the greatest portion of body weight.The human body consists of 45% to 75% water, depending on age and sex. 水是至关重要的,是对身体体重最大的一部分。人的身体有45%至75%的水,根据年龄和性别有所不同。 Water as a percentage of body weight Water Compartment Infant (%) Adult (%) Man Woman Elderly Person (%) Extracellular Intravascular Interstitial Intracellular Total body water 4 25 4 11 5 10 5 15 48 45 35 25 77 60 50 45 Water (H2o) is vital to human life.The body cannot carry on most of its activities without it. Water performs many significant functions in the human body .It provides an efficient medium for delivery of nutrients to the cells and export of waste products from the cells.It is especially important in regulation of blood pressure and fluid and electrolyte balance. 流体和电解质的平衡 Primary solvent主要溶剂within the body Primary compound in all body fluids在所有体液中主要化合物 Suspension agent Helps regulate body temperature,body pH,and fluid pressures inside and outside cells Assists or participates in chemical reactions May be end product of chemical reactions可能是化学反应的最终产物 Transports nutrients and oxygen to cells Transports waste products away from cells Acts as bumper to protect cells and organs Lubricates to prevent outer walls(parietal) from rubbing against inner walls(visceral) of organs Water in solution with other substances Participates in maintenance of blood pressure Helps regulate acid-base and fluid-electrolyte balance Facilitates the use of water-soluble victamins(C and B-complex)便于使用的水溶性victamins Water in Solution with Other substances Special characteristics of water A great difference in temperature is needed to bring about a physical change in water. Water directly and indirectly participates in all chemical reactions that occur in the body. Water is a good solvent. Water exerts pressure against the walls