2.2 Water Flashcards
What are examples of hydrophilic substances?
Hydrophilic substances include glucose, fructose, and most salts, which are soluble in water due to their polar nature.
What are examples of hydrophobic substances?
Hydrophobic substances include fats, oils, and cholesterol, which do not dissolve in water due to their non-polar nature.
How does hydrogen bonding contribute to water’s unique properties?
Hydrogen bonding between water molecules results in cohesion, adhesion, high specific heat capacity, and a high latent heat of vaporization, contributing to water’s solvent capabilities and its thermal properties.
What is an example of cohesion’s benefit to living organisms?
Cohesion allows water to be transported up from the roots to the leaves of plants and enables insects like pond skaters to float on water.
How does adhesion benefit living organisms?
Adhesion helps in the capillary action, assisting the pumping action of the heart and enabling water to move through blood vessels and up plant stems against gravity.
Provide an example of how water’s thermal properties benefit living organisms.
Water’s high specific heat capacity stabilizes aquatic ecosystems’ temperatures, making them more stable environments for organisms.
How does water’s solvent property benefit living organisms?
Water dissolves vital substances like glucose and minerals, facilitating their transport in blood plasma or within plants from roots to leaves.
What is the significance of comparing the thermal properties of water to methane?
Comparing water to methane highlights the role of hydrogen bonding in water’s higher boiling point, specific heat capacity, and latent heat of vaporization, emphasizing water’s importance in biological systems compared to non-polar substances like methane.
How are amino acids transported in relation to their solubility in water?
Amino acids with hydrophilic R groups dissolve easily in water and are transported in higher concentrations in blood, whereas those with hydrophobic R groups are less soluble and transported in lower concentrations.
How is cholesterol transported in the body considering its hydrophobic nature?
Cholesterol is transported in blood through lipoproteins, which encase the hydrophobic cholesterol molecules, allowing them to move through the aqueous environment of blood plasma.
What is the significance of water’s polarity in biological systems?
Water’s polarity, due to its unequal sharing of electrons between oxygen and hydrogen atoms, allows for hydrogen bonding with other molecules, crucial for solvency, cohesion, adhesion, and water’s thermal properties.
Define hydrogen bonding and its importance in water.
Hydrogen bonding in water occurs when the partial positive charge of hydrogen atoms in one water molecule attracts the partial negative charge of the oxygen atom in another. This is essential for water’s cohesive and adhesive properties.
What makes a substance hydrophilic or hydrophobic?
Substances that interact well with water, dissolving in it, are hydrophilic (‘water-loving’), whereas those that repel water, not dissolving in it, are hydrophobic (‘water-fearing’).
How do hydrophilic and hydrophobic properties affect the transport of biological molecules?
Hydrophilic molecules dissolve easily in water and are transported in blood plasma, while hydrophobic molecules, being water-insoluble, are transported via other means like lipoproteins.
Compare the thermal properties of water and methane.
Water has a high boiling point, high specific heat capacity, and high latent heat of vaporization due to hydrogen bonding, whereas methane, being non-polar, has lower thermal properties.
