Biochemistry Unit 1: Introduction and Water & pH - Vocabulary

Vocabulary flashcards covering key biochemistry terms and concepts from Unit 1: Introduction and Water & pH.

Biochemistry

The study of the molecular basis of life; understanding how biological molecules give rise to cellular processes.

Enzymes

Biological catalysts (usually proteins) that accelerate chemical reactions in living systems.

Metabolism

The sum of all chemical reactions in living organisms that sustain life.

Nutrients

Substances required for growth, energy, maintenance, and proper function of the body.

Vitalism

The belief that organic compounds can only be produced by living organisms; disproved by Wöhler's synthesis of urea.

Friedrich Wöhler

Chemist who disproved vitalism by synthesizing urea in 1828 from ammonium cyanate.

Urea

An organic compound and waste product of animal metabolism; first synthesized from ammonium cyanate, showing life’s chemistry can be produced in the lab.

Eduard Buchner

Scientist who demonstrated alcoholic fermentation in cell-free yeast extracts, proving enzymes can catalyze reactions outside living cells.

Miller–Urey experiment

1952 experiment simulating early Earth conditions that produced amino acids, supporting chemical origins of life.

Amino acids

Building blocks of proteins; formed in the Miller–Urey experiment under simulated early Earth conditions.

Cell theory

Idea that all organisms are composed of cells; formulated by Schleiden and Schwann in the 1840s.

Schleiden

Botanist who proposed that plants are composed of cells and helped formulate the cell theory.

Schwann

Physiologist who proposed that animals are composed of cells and helped formulate the cell theory.

Carl Neuberg

Scientist credited with coining the term 'biochemistry' in the 1870s.

Embden–Meyerhof pathway

Glycolytic pathway (glycolysis) describing the breakdown of glucose to pyruvate; described by Embden and Mayerhoff in 1925.

Krebs cycle

Citric acid cycle; central energy-producing pathway described by Hans Krebs in 1937.

DNA double helix

The double helical structure of DNA proposed by Watson and Crick in 1953.

Watson

Co-discoverer of the DNA double-helix structure.

Crick

Co-discoverer of the DNA double-helix structure.

Rotary Engine

ATP synthase mechanism described by Boyer and Walker in 1997 that generates ATP.

ATP

Adenosine triphosphate; the cell’s main energy currency.

ADP

Adenosine diphosphate; substrate that becomes ATP upon phosphorylation.

Sodium–potassium pump

Na+/K+-ATPase pump maintaining membrane potential by exchanging Na+ and K+ ions across the cell membrane.

Electron microscope

Instrument allowing high-resolution imaging of cellular structures; development credited to Ruska.

Prion

Proteinaceous infectious particle causing diseases such as mad cow disease; associated with discovery by Prusiner in 1997.

Ruska

Scientist who developed the electron microscope, enabling advanced cellular imaging.

Hydrogen bonds

Intermolecular bonds contributing to water’s high heat capacity and unique properties.

Water

The most important and abundant inorganic compound in life; a polar solvent and reactant in biochemical reactions.

Solvent

Substance (like water) that dissolves solutes.

Solute

Substance dissolved by a solvent.

Hydrophilic

Molecules or ions that are water-loving and dissolve easily in water.

Hydrophobic

Molecules that repel water and are poorly soluble in water.

Hydrolysis

Decomposition reaction in which water is added to break bonds, splitting larger molecules into smaller ones.

Dehydration synthesis

Condensation reaction where two smaller molecules join to form a larger molecule with removal of water.

pH scale

A measure of acidity/alkalinity from 0 to 14; 7 is neutral; below 7 is acidic, above 7 is basic.

Acid

A substance that increases H+ concentration in solution (proton donor).

Base

A substance that decreases H+ concentration by accepting protons (proton acceptor).

Buffer system

Systems that maintain pH by converting strong acids/bases to weak acids/bases (examples: bicarbonate, phosphate, protein).

Acidosis

Condition where blood pH falls below 7.35.

Alkalosis

Condition where blood pH rises above 7.45.

Interstital fluid

ECF component; fluid in the spaces between tissue cells, making up about 80% of ECF.

Plasma

ECF component; liquid portion of blood, comprising about 20% of extracellular fluid.

Intracellular fluid (ICF)

Fluid inside cells; about two-thirds of total body water; rich in potassium, phosphate, magnesium, and protein.

Extracellular fluid (ECF)

Fluid outside cells; about one-third of total body water; rich in sodium, chloride, and bicarbonate.

Sodium (Na+)

Most abundant cation in extracellular fluid; regulated by aldosterone, ADH, and ANP.

Potassium (K+)

Most abundant cation in intracellular fluid; regulated mainly by aldosterone.

Calcium (Ca2+)

Extracellular cation; stored in bones; regulated by PTH and calcitriol; essential for bone, clotting, neurotransmitter release, and muscle function.

Phosphate (PO4^3−)

Intracellular anion; regulated by PTH and calcitriol.

Magnesium (Mg2+)

Intracellular cation; cofactor for metabolism and Na+/K+ pump.

Bicarbonate (HCO3−)

Extracellular anion; regulated by kidneys; part of the bicarbonate buffering system.

Osmolarity

Measure of solute concentration; changes can cause cells to shrink or swell.