Chapter 4: From Chemistry to Energy to Life

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Chemistry and the Environment

conservation of matter atoms

protons (+)neutrons electrons (-)

Isotopes have a different number of neutrons in the atom– some are radioactive– half-life of minutes to millions of years

Ion is an atom that gains an electron (-) or loses one (+)– Ca+2 calcium which has lost 2 electrons

Compounds

Organic

have carbon (C), oxygen (O), hydrogen (H) and nitrogen (N) in them as the core

example: CO2 carbon dioxide Inorganic

any other compound

example: NaCl table salt

Solutions

mixture of substances– air is a solution of gases– tap water is a solution of liquids– human blood

pH

0 - 14 0-7 acid 7 is neutral 7-14 base

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Macromolecules

building blocks of life large in size compared to other simple

molecules like water and sugar proteins, carbohydrates, lipids, nucleic acids

Synthetic Polymers

plastics man-made not present in nature derived from hydrocarbons resist chemical breakdown can create problems in wildlife

Compartmentalization of Macromolecules

natural macromolecules make up cells, the unit of life, from the simple bacteria to more complex organisms like you and I.

Prokaryotes Eukaryotes

Energy

potential energypotential energy: energy present in a molecule

kinetic energykinetic energy: energy produced by the movement of a molecule

chemical energychemical energy: energy held in the bonds of a molecule

Thermodynamics: Energy conservation

First LawFirst Law: energy is not created nor destroyed, its only transformed.– energy in food

Second LawSecond Law: nature of energy will change from more ordered one to a more chaotic one.– decomposition of a dead organism

Light Energy Produces Food

autotrophsautotrophs: produce their own food with the use of solar energy known as photosynthesis. Example→plants which become the primary producers

6CO2 + 6H2O → C6H12O6 + 6O2 carbon water glucose oxygen dioxide

Cellular Respiration Releases Chemical Energy

heterotrophsheterotrophs: consume autotrophs to obtain energy. example→animals which become the primary consumers

C6H12O6 + 6O2 → 6CO2 + 6H2O + energy

Chemosysthesis

chemical-bond energy of hydrogen sulfide (H2S) to transform inorganic carbon into organic compounds.

Present in bacteria found in the hydrothermal vents at the bottom of the ocean

6CO2 + 6H2O → C6H12O6 + 3H2SO4

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Origin of Life

Primordial soupPrimordial soup: simple inorganic compounds under special conditions formed the first organic compounds.

Panspermia hypothesisPanspermia hypothesis: microbes from outer space came to contact with earth and evolved.

Chemoautotrophic theoryChemoautotrophic theory: proposed the bacteria from the hydrothermal vents came first.

Evolution through the Fossil records

comparison of genes Prokaryotes

– history of life bacteria– Archaea

Eukaryotes– protists– plants– fungi– animalsTHE END

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