Ch. 4: From Chemistry to Energy to Life
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Transcript Ch. 4: From Chemistry to Energy to Life
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 energy: energy present in a
molecule
kinetic energy: energy produced by the
movement of a molecule
chemical energy: energy held in the bonds of
a molecule
Thermodynamics: Energy
conservation
First Law: energy is not created nor
destroyed, its only transformed.
–
energy in food
Second Law: nature of energy will change
from more ordered one to a more chaotic
one.
–
decomposition of a dead organism
Light Energy Produces Food
autotrophs: 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
heterotrophs: consume autotrophs to obtain
energy. example→animals which become the
primary consumers
C6H12O6 + 6O2 → 6CO2 + 6H2O + energy
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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
Origin of Life
Primordial soup: simple inorganic
compounds under special conditions formed
the first organic compounds.
Panspermia hypothesis: microbes from outer
space came to contact with earth and
evolved.
Chemoautotrophic 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
– animals
THE END
–
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