Grade 11 General Science MET 7 Lesson 7: Chemists and How They Have Made an Impact on Our Lives

Vocabulary flashcards covering Louis Pasteur's chemical and biological contributions, germ theory, pasteurization, fermentation, and vaccination based on the Grade 11 General Science module.

Molecular Asymmetry

A property discovered by Louis Pasteur in tartaric acid crystals where molecules exist in two mirror-image forms that cannot be perfectly superimposed, demonstrating how a substance's chemical structure is tied to its properties.

Fermentation

A process caused by microorganisms that converts sugar into products like alcohol or acid.

Spontaneous Generation

The disproven idea that living things can arise on their own from non-living matter.

Pasteurization

A heat-treatment process developed by Louis Pasteur where liquids like wine or milk are heated to a specific temperature and cooled to kill harmful microorganisms responsible for spoilage without ruining the taste.

Germ Theory of Disease

The principle established by Louis Pasteur that specific microorganisms, such as bacteria, invade the body and cause illness.

Infectious Disease

An illness caused by microorganisms that can spread from one host to another.

Vaccine / Vaccination

Exposure to a weakened disease-causing organism that trains the immune system to resist future infection.

Antiseptic / Sterilization

Techniques and chemical agents that kill or prevent the growth of harmful microorganisms, especially on wounds, surgical tools, and in hospital environments.

Miasma Theory

An old medical belief that disease was caused by 'bad air' or foul-smelling vapors arising from rotting matter, sewage, or swamps.

Four Humors Theory

An ancient Greek theory asserting that the human body was composed of four fluids—blood, phlegm, yellow bile, and black bile—and that illness occurred when these fluids were out of balance.

Louis Pasteur

A French chemist (1822–1895) whose research combined chemistry and biology to revolutionize the understanding of disease, pasteurization, germ theory, and vaccines.

Swan-Necked Flask Experiment

An experiment conducted by Louis Pasteur between 1859 and 1864 using long, curved-neck flasks that allowed air entry while trapping airborne particles, proving that microorganisms come from the environment and disproving spontaneous generation.

Joseph Lister

A British surgeon who, inspired by Louis Pasteur's germ theory, pioneered antiseptic surgery in the 1860s using a carbolic acid spray to kill microbes during operations.

Ignaz Semmelweis

A Hungarian physician who demonstrated that handwashing by doctors significantly reduced patient deaths in maternity wards prior to the formal establishment of germ theory.

Chicken Cholera Breakthrough (1879)

An accidental discovery made when chickens inoculated with a weakened culture of bacteria did not contract cholera and subsequently resisted fresh, potent doses, revealing the fundamental principle of vaccination.

Rabies Vaccine (1885)

The first successful vaccine developed against a viral disease, created and administered by Louis Pasteur using the principle of weakened microorganisms.

Silkworm Disease Contribution (1865)

Pasteur's application of microscope-based methods to identify the microorganism killing silkworms, developing techniques to remove infected eggs and saving the French silk industry.

Molecular Asymmetry

A chemical property discovered by Louis Pasteur while studying tartaric acid crystals, where molecules exist in non-superimposable mirror-image forms, establishing that a substance's structural arrangement directly governs its chemical properties and behavior.

Pasteurization

A food preservation heat-treatment technique developed by Louis Pasteur where liquids like milk, juice, or wine are heated to a specific temperature and then rapidly cooled to destroy pathogenic and spoilage microorganisms without altering the product's flavor or quality.

Swan-Necked Flask Experiment

A scientific experiment conducted by Louis Pasteur using long, curved-necked flasks that allowed air exposure while trapping airborne microbes in the bend, successfully disproving the theory of spontaneous generation by demonstrating that microbes originate from environmental contaminants.

Germ Theory of Disease

The foundational biological principle established by Louis Pasteur stating that specific diseases are caused by the invasion of the body by specific pathogenic microorganisms (such as bacteria), replacing ancient theories like miasma and the four humors.

Miasma Theory

An obsolete medical belief preceding germ theory which asserted that diseases originated and spread through 'bad air' or noxious, foul-smelling vapors emitted from decaying organic matter, sewage, and swamps.

Four Humors Theory

An ancient Greek medical model proposing that human health and illness were controlled by the balance of four primary bodily fluids: blood, phlegm, yellow bile, and black bile.

Joseph Lister's Medical Innovation

The introduction of antiseptic surgery in the 1860s using a carbolic acid spray to sterilize surgical instruments and wound sites, directly inspired by Louis Pasteur's work on germ theory and fermentation.

Chicken Cholera Breakthrough (1879)

An accidental discovery by Louis Pasteur showing that chickens injected with an aged, weakened bacterial culture suffered no harm and developed immunity against subsequent lethal doses, revealing the core mechanism of artificial vaccination.

Rabies Vaccine (1885)

The first successful viral vaccine created and administered by Louis Pasteur, developed using weakened cultures of the pathogen to induce protective immune memory.

Active Ingredient

The specific chemical component in a household or personal care product formulation that is directly responsible for delivering its primary intended physical or chemical effect, such as ethyl alcohol in hand sanitizers or fluoride in toothpaste.

Surfactant

A surface-active chemical compound found in soaps, shampoos, and detergents that lowers the surface tension of water, enabling it to emulsify, lift, and remove hydrophobic dirt, grease, and oils.

Humectant

A hygroscopic ingredient added to personal care products, such as skin lotions and toothpaste, designed to attract and retain moisture, preventing the product or skin from drying out.

Sodium Hypochlorite

The active chemical compound found in liquid household bleach responsible for oxidizing organic stains, breaking down pigments, and acting as a powerful disinfectant.

Sodium Bicarbonate

Commonly known as baking soda ($NaHCO_3$), a chemical compound used in household cleaning to neutralize odors, act as a mild abrasive, and serve as a leavening agent in baking.

Food and Drug Administration (FDA) Role in Consumer Safety

The Philippine government regulatory agency tasked with monitoring and enforcing quality, efficacy, and safety standards for health products, cosmetics, household chemicals, and food items.

Department of Environment and Natural Resources (DENR) Environmental Mandate

The Philippine government department responsible for managing and regulating environmental safety, pollution prevention, and proper disposal of toxic chemicals and hazardous wastes.

Indicators of a Chemical Reaction

Observable physical and chemical signs that a chemical change has occurred, including distinct color changes, temperature variations (heat release or absorption), light emission, gas evolution (bubbling), and precipitate formation.

Combination Reaction

A reaction type where two or more simple reactants synthesize into a single complex product, taking the general form $X + Y \rightarrow XY$, exemplified by iron rusting ($4Fe_{(s)} + 3O_{2(g)} \rightarrow 2Fe_2O_{3(s)}$).

Decomposition Reaction

A chemical process where a single complex compound breaks down into two or more simpler elements or compounds, taking the general form $XY \rightarrow X + Y$, such as the thermal breakdown of baking soda above $80\,^\circ\text{C}$ ($2NaHCO_{3(s)} \rightarrow Na_2CO_{3(s)} + CO_{2(g)} + H_2O_{(g)}$).

Acid-Carbonate Reaction

A specific neutralization reaction where an acid reacts with a metal carbonate or bicarbonate to yield three distinct products: a chemical salt, liquid water, and carbon dioxide gas ($CaCO_{3(s)} + 2HCl_{(aq)} \rightarrow CaCl_{2(aq)} + CO_{2(g)} + H_2O_{(l)}$).

Combustion Reaction

An exothermic chemical reaction occurring between a fuel and oxygen gas ($O_{2(g)}$), producing light, heat, and oxidized gases such as carbon dioxide ($CO_{2(g)}$) and water vapor ($H_2O_{(g)}$).

Catabolism

The metabolic branch consisting of enzymatic breakdown processes that degrade complex food macronutrients (carbohydrates, proteins, fats) into simpler molecular units, releasing stored chemical energy in the form of $ATP$.

Anabolism

The constructive metabolic phase in which living cells utilize cellular energy ($ATP$) to synthesize complex macromolecules (such as proteins and nucleic acids) from simple precursor molecules for cellular growth and repair.

Cellular Respiration

A vital metabolic pathway occurring in living cells where glucose ($C_6H_{12}O_6$) is biochemically oxidized in the presence of oxygen to generate usable cellular energy ($ATP$), yielding carbon dioxide ($CO_2$) and water ($H_2O$) as byproducts.

Ocean Acidification

An environmental process driven by elevated atmospheric carbon dioxide ($CO_2$) dissolving into seawater to form carbonic acid ($H_2CO_3$), reducing ocean pH and depleting free carbonate ions essential for marine shell and coral skeleton formation.

Acid Rain Formation

An environmental phenomenon caused by industrial fossil fuel combustion emitting sulfur dioxide ($SO_2$) and nitrogen oxides ($NO_x$), which react with atmospheric water vapor to form sulfuric and nitric acids, acidifying soils and aquatic ecosystems.