Ch. 3, Water and Life bio

Water

A biological medium that supports all life, covering ¾ of the Earth's surface in different states (liquid, solid, gas).

Emergent properties of water

Four key properties of water that facilitate life: cohesive behavior, ability to moderate temperature, expansion upon freezing, and versatility as a solvent.

Solute

The substance that is dissolved in a solution.

Solvent

The dissolving agent in a solution, commonly water.

Hydrophilic

Substances that have an affinity for water and can interact with it.

Hydrophobic

Substances that do not have an affinity for water and repel it.

Cohesion

The ability of water molecules to stick together, which helps transport water in plants.

Adhesion

Attraction between different substances, which aids in countering gravitational pull.

Surface Tension

The measure of difficulty to stretch or break the surface of a liquid; high in water due to hydrogen bonding.

Specific Heat

The amount of energy required to raise the temperature of 1 gram of a substance by 1°C.

Heat Sink

Large bodies of water that moderate temperature in their environments.

Expansion upon Freezing

Water expands when it freezes, making ice less dense than liquid water.

Hydration Shell

The sphere of water molecules that surrounds ions or polar molecules in solution.

Acids

Substances that increase hydrogen ion concentration in a solution.

Bases

Substances that reduce hydrogen ion concentration in a solution.

pH Scale

A scale used to measure the acidity or basicity of a solution, ranging from 0 (acidic) to 14 (basic).

Buffer

A substance that minimizes pH changes in solutions, typically consisting of a weak acid and its conjugate base.

Ocean Acidification

The decrease in pH of ocean waters due to the absorption of CO2 from the atmosphere.

Molecular Mass

The sum of the masses of all atoms in a molecule.

Mole

A unit for measuring the number of molecules, where 1 mole = 6.02 x 10^23 molecules (Avogadro's Number).

Molarity

The number of moles of solute per liter of solution.

Carbonate

A compound formed by the reaction of carbon dioxide with water, playing a key role in ocean acidification.

Bicarbonate

A weak acid that plays a role in the buffering system of biological fluids.

Hydrogen Bond

A weak bond between molecules, important for the properties of water.

Polar Covalent Bonds

Bonds where electrons are shared unequally, resulting in partial positive and negative charges.

Temperature Moderation

Water's ability to absorb and release heat without significant changes to its own temperature.

Capillary Action

The ability of water to flow in narrow spaces against gravity due to cohesion and adhesion.

Glucose

A simple sugar with the molecular formula C6H12O6, commonly found in living organisms.

High Specific Heat

Water's property of requiring significant energy to change its temperature.

Dissociation

The process by which a compound separates into its constituent ions.

Ionization

The process of forming ions by breaking ionic bonds, relevant in acids and bases.

pH Indicator

A substance that changes color in response to changes in pH, used to measure acidity.

Water Vapor

The gaseous state of water, significant in weather patterns and climate.

Polarity of Water

The distribution of electrical charge across water molecules, which leads to its unique properties.

Thermal Inertia

The resistance of a substance to change in temperature, notable in water.

Acid-Base Reaction

A reaction that involves the transfer of hydrogen ions between substances.

Caloric Value

The amount of heat energy required to raise the temperature of water, often represented in dietary terms.

Chemical Equilibrium

A state in a solution when the rates of the forward and reverse reactions are equal.

Hydrogen Ion (H+)

A positively charged ion formed when an acid dissociates in a solution.

Hydroxide Ion (OH-)

A negatively charged ion formed when a base dissociates in a solution.

Biological Fluid pH Range

Most biological fluids have a pH between 6 and 8, maintained by buffering systems.

Ocean Carbon Cycle

The cycle involving the uptake of CO2 by oceans and its impact on marine life.

Solubility

The ability of a substance to dissolve in a solvent, influenced by polarity and ionic nature.

Electrolyte

A substance that dissociates into ions in solution, conducting electricity.

Cohesive Properties

The properties of water that allow it to resist separation and promote surface tension.

Liquid Water

The state of water at room temperature, characterized by mobile hydrogen bonds.

Freezing Point

The temperature at which water transitions from liquid to solid, defined at 0°C.

Atmospheric CO2

Carbon dioxide present in the atmosphere that contributes to ocean acidification.

Buffering Capacity

The ability of a solution to resist changes in pH upon addition of acids or bases.

Hydration Energy

The energy released when solvent molecules surround and stabilize ions in solution.

Anions

Negatively charged ions that often interact with water through hydrogen bonding.

Cations

Positively charged ions that interact with water, forming hydration shells.

Colloidal Solution

A mixture where tiny particles are dispersed throughout a liquid.

Isotonic Solution

A solution with equal concentrations of solute and solvent, preventing cell shrinkage or swelling.

Hypertonic Solution

A solution with a higher concentration of solutes compared to another solution.

Hypotonic Solution

A solution with a lower concentration of solutes compared to another solution.

Biochemical Buffers

Buffers that help maintain stable pH levels in biological systems.

Carbon Footprint

The total emissions of greenhouse gases caused by an individual, organization, or product.

Denaturation

The process where proteins lose their functional shape due to environmental stress, such as changes in pH.

Aquatic Ecosystem

A community of organisms living in water, affected by pH and solute concentration.

pH Tagging

A technique used to label substances based on their acidity or basicity.

Hydrophobic Effect

The tendency of nonpolar substances to aggregate in aqueous solutions to avoid contact with water.

Osmoregulation

The process by which organisms regulate their internal water and solute concentrations.

Carbon Sequestration

The process of capturing and storing atmospheric carbon dioxide to reduce global warming.

Saturation State

A ratio that indicates the availability of carbonate ions in relation to calcium carbonate formation.

Environmental Impact Assessment

A process to evaluate the potential environmental effects of a proposed project.

Eutrophication

Nutrient enrichment in water bodies, leading to increased growth of algae and other plants.

Biodegradation

The breakdown of organic substances by microorganisms.

Photosynthesis

The process used by plants to convert light energy into chemical energy, requiring water.

Respiration

The biochemical process in which organisms convert nutrients into energy under aerobic or anaerobic conditions.

Halophiles

Microorganisms that thrive in high-salinity environments.