Importance of Water in Biology

70%

Approximately 500 grams

80 to 95%

<p>5 to 15%</p> Signup and view all the answers

<p>105°</p> Signup and view all the answers

<p>Partial negative charge</p> Signup and view all the answers

<p>85 to 95%</p> Signup and view all the answers

<p>The hydrogen atoms</p> Signup and view all the answers

<p>Breaking hydrogen bonds requires energy, which increases the surface area and thus contributes to surface tension.</p> Signup and view all the answers

<p>Surface tension at evaporative surfaces creates physical forces that pull water through the plant's vascular system.</p> Signup and view all the answers

<p>Tensile strength is the maximum force per unit area that a column of water can withstand before breaking.</p> Signup and view all the answers

<p>Studies show that water in capillaries can resist tensions lower than -30 MPa, indicative of its tensile strength.</p> Signup and view all the answers

<p>Gas bubbles reduce the tensile strength of water columns and may lead to cavitation if allowed to expand.</p> Signup and view all the answers

<p>Water's small size and polar nature make it an effective solvent for a variety of substances, especially ionic ones.</p> Signup and view all the answers

<p>Hydrogen bonds between water molecules and ions reduce electrostatic interactions, increasing the solubility of the ions.</p> Signup and view all the answers

<p>Water droplets are spherical due to high surface tension, which minimizes surface area for a given volume.</p> Signup and view all the answers

<p>Water forms a hydration shell around macromolecules, which minimizes their interactions.</p> Signup and view all the answers

<p>Water has a much higher dielectric constant than non-polar organic liquids like benzene and hexane.</p> Signup and view all the answers

<p>Water's high specific heat capacity enables it to absorb large amounts of heat without significant temperature changes, stabilizing aquatic environments.</p> Signup and view all the answers

<p>The highly ordered structure of liquid water allows it to conduct heat efficiently away from localized heat sources.</p> Signup and view all the answers

<p>Water can dissolve many substances due to its polarity and ability to form hydration shells around ions and molecules.</p> Signup and view all the answers

<p>Hydrogen bonds require energy to break, so more energy is needed to raise the temperature of water compared to other liquids.</p> Signup and view all the answers

<p>High dielectric constants reduce the electrostatic forces between charged solutes, facilitating their dissolution in water.</p> Signup and view all the answers

<p>Water's high specific heat capacity provides thermal stability, protecting plant tissues from temperature fluctuations.</p> Signup and view all the answers

<p>It prevents localized overheating by allowing heat to be dispersed throughout the cell, maintaining a stable internal temperature.</p> Signup and view all the answers

<p>The heat of vaporization is about 44 kJ mol$^{-1}$, which leads to a cooling effect as energetic molecules escape during evaporation.</p> Signup and view all the answers

<p>Evaporation removes the most energetic molecules from the surface, leaving behind the less energetic, cooler molecules.</p> Signup and view all the answers

<p>The heat of fusion for water is 335 J g$^{-1}$, indicating a high energy requirement to change ice to liquid water, due to strong hydrogen bonds.</p> Signup and view all the answers

<p>Flooding the groves with water before freezing releases heat during fusion, thus protecting the trees from frost damage.</p> Signup and view all the answers

<p>Hydrogen bonding increases water's resistance to flow, making its viscosity higher than that of most liquids.</p> Signup and view all the answers

<p>It allows cells to undergo biochemical reactions without significant temperature fluctuations, ensuring metabolic processes can occur efficiently.</p> Signup and view all the answers

<p>The high heat of vaporization aids in cooling during transpiration, while viscosity influences the movement of water through plant tissues.</p> Signup and view all the answers

<p>1.0 centipoise.</p> Signup and view all the answers

<p>Ethanol has a viscosity of 1.2 centipoise, making it slightly more viscous than water.</p> Signup and view all the answers

<p>Near 4℃.</p> Signup and view all the answers

<p>Ice is less dense than liquid water.</p> Signup and view all the answers

<p>Water acts as a reservoir of H+ ions, helping to regulate pH levels.</p> Signup and view all the answers

<p>Viscosity decreases with increasing temperature.</p> Signup and view all the answers

<p>It allows sunlight to penetrate for photosynthesis and other biological processes.</p> Signup and view all the answers

<p>The volume occupied by 1 g of water increases as temperature deviates from 4℃.</p> Signup and view all the answers