Organic and Inorganic Biochemistry and the Cell

Vocabulary practice flashcards covering organic and inorganic biochemistry, properties of water, acids, bases, pH, buffers, carbohydrates, lipids, and key chemical reactions from the lecture.

Biochemistry

The study of the chemical composition and reactions of living matter.

Inorganic compounds

Chemical compounds that do not contain carbon (with exceptions like $CO_2$ and $CO$), including water, salts, and many acids and bases.

Organic compounds

Carbon-containing chemical compounds that are usually large, covalently bonded, and include carbohydrates, fats, proteins, and nucleic acids.

High heat capacity

A property of water defining its ability to absorb and release heat with little temperature change, preventing sudden changes in temperature.

High heat of vaporization

A property of water where evaporation requires large amounts of heat, serving as a useful cooling mechanism.

Reactivity (of water)

A property of water characterized by a high impulse to undergo chemical reactions, making it a necessary part of hydrolysis and dehydration synthesis reactions.

Cushioning (of water)

A physical property of water that protects certain organs from physical trauma, such as cerebrospinal fluid cushioning nervous system organs.

Polar solvent properties

The ability of water to dissolve and dissociate ionic substances and form hydration (water) layers around large charged molecules such as proteins.

Salts

Ionic compounds that dissociate into separate cations and anions in water, excluding $H^+$ and $OH^-$ ions.

Electrolytes

Substances (including all ions) that can conduct electrical currents in solution.

Cations

Positively charged molecules or ions.

Anions

Negatively charged molecules or ions.

Acids

Electrolytes that act as proton donors, releasing hydrogen ions ($H^+$), which are bare protons with no electrons, in solution.

Bases

Electrolytes that act as proton acceptors by picking up $H^+$ ions in solution and usually releasing hydroxyl ions ($OH^-$).

pH

A logarithmic measurement of the concentration of hydrogen ions ($[H^+]$) in moles per liter in a solution, ranging on a scale from $0$ to $14$.

Neutral solutions

Solutions containing equal numbers of $H^+$ and $OH^-$ ions, maintaining a pH of $7$ (where $[H^+] = 10^{-7}\text{ M}$ in pure water).

Neutralization reaction

A displacement reaction occurring when acids and bases are mixed together, forming water and a salt: $\text{Base} + \text{Acid} \rightarrow \text{Salt} + \text{Water}$.

Buffers

Systems composed of a weak acid and a weak base that resist abrupt and large swings in pH by releasing hydrogen ions if pH rises or binding hydrogen ions if pH falls.

Dehydration synthesis

A reaction that joins monomers into polymers by covalent bonds through the removal of an $OH$ group from one monomer and an $H$ from the other, releasing a water molecule ($H_2O$).

Hydrolysis

A reaction that breaks down polymers into monomers by adding a water molecule ($H_2O$), attaching an $OH$ group to one monomer and an $H$ to the other.

Carbohydrates

Organic molecules including sugars and starches composed of C, H, and O, where hydrogen and oxygen are present in a $2:1$ ratio.

Monosaccharides

Single sugar units that represent the smallest building blocks (monomers) of carbohydrates, categorized as pentoses (ribose, deoxyribose) or hexoses (glucose, fructose, galactose).

Disaccharides

Double sugars (such as sucrose, maltose, and lactose) formed by the dehydration synthesis of two monosaccharides that are too large to passively move through cell membranes.

Polysaccharides

Polymers of monosaccharides formed by dehydration synthesis of many sugar monomers, which are not very soluble.

Starch

A storage polysaccharide carbohydrate used by plants.

Glycogen

A storage polysaccharide carbohydrate used by animals.

Lipids

Organic molecules insoluble in water containing C, H, and O (with less oxygen than carbohydrates) and sometimes P; includes triglycerides, phospholipids, steroids, and eicosanoids.

Triglycerides

Lipids composed of three fatty acids bonded to a glycerol molecule by dehydration synthesis, serving functions in energy storage, insulation, and protection.

Saturated fatty acids

Fatty acid chains where all carbon atoms are linked by single covalent bonds, holding the maximum number of hydrogen atoms to create linear molecules that pack tightly as solids at room temperature.

Unsaturated fatty acids

Fatty acid chains with one or more double bonds between carbon atoms, creating kinks that prevent tight packing and keeping them liquid at room temperature.

Trans fats

Modified unsaturated fatty oils that structurally resemble saturated fats and are considered unhealthy.

Phospholipids

Modified triglycerides composed of a glycerol, two fatty acids, and a phosphorus-containing group, possessing a polar hydrophilic head and nonpolar hydrophobic tails.

Steroids

Lipids consisting of four interlocking ring structures.

Cholesterol

The most important steroid, produced by the liver and found in animal products, serving as a starting material for synthesizing vitamin D, steroid hormones, and bile salts.

Eicosanoids

Lipids derived from arachidonic acid found in cell membranes, playing essential physiological roles.

Prostaglandins

The most important eicosanoids, involved in blood clotting, control of blood pressure, inflammation, and labor contractions.