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Biology (level 0
part 2)
1 Properties of Matter
1.1 Atoms
1.1.1 Basic unit of matter;
everything is made of atoms
1.1.1.1 Protons
1.1.1.1.1 Positive charge
1.1.1.1.1.1
1.1.1.2 Neutrons
1.1.1.2.1 Negative charge
1.1.1.2.1.1 Combine to form nucleus
1.1.1.3 Electrons
1.1.1.3.1 Negative charge
1.1.1.3.1.1 Surrounds nucleus
1.2 Elements
1.2.1 pure substance that consists
of one type of atom
1.2.1.1 More than 100
elements are known
1.2.1.2 Isotopes
1.2.1.2.1 Atoms of the same element that differ
in the number of neutrons they contain
1.2.1.2.1.1 All isotopes of the same element
have same number of electrons
1.3 Chemical Compounds/Bonds
1.3.1 Chemical Compounds
1.3.1.1 Substance formed by the chemical combination
of two or more elements in definite proportions
1.3.1.1.1 Shown as chemical formula
1.3.1.1.1.1 Example: water is H20
1.3.1.1.1.2 Example: table salt is NaCl
1.3.1.1.2 Physical properties of a compound
are usually different from those of
the elements from which it formed
1.3.2 Chemical Bonds
1.3.2.1 Atoms in compounds are held
together by chemical bonds
1.3.2.1.1 Ionic bonds
1.3.2.1.1.1 Formed when one or more electrons are
transferred from one atom to another
1.3.2.1.1.1.1 Ions
1.3.2.1.1.1.1.1 An atom that loses or gains electrons
1.3.2.1.2 Covalent bonds
1.3.2.1.2.1 Formed when electrons
are shared by atoms
1.3.2.1.2.1.1 Molecule
1.3.2.1.2.1.1.1 The structure that results when atoms
are joined together by covalent bonds
2 Properties of Water
and Suitabilty for Life
2.1 Polarity
2.1.1 A molecule in which the
charges are unevenly distributed
2.1.2 similar to a magnet with two poles
2.2 Hydrogen Bonding
2.2.1 Solvent
2.2.1.1 Substance in which the solute dissolves
2.2.2 Water expands slightly upon freezing
2.2.2.1 Makes ice less dense than water
2.2.2.1.1 That's why ice floats
2.2.3 Attraction between a hydrogen atom
with a partial positive and another
atom with a partial negative charge
2.2.4 Heat Capacity
2.2.4.1 Takes large amount of heat energy to
cause the molecules to move faster
3 Importance of Carbon to Life
3.1 Carbon has four valence electrons,
allowing them to form strong covalent
bonds with many other elements
3.1.1 One carbon atom can bond to another
which gives carbon the ability to form
chains that are almost unlimited in length
3.1.1.1 Macromolecules
3.1.1.1.1 Carbohydrates
3.1.1.1.1.1 Living things use carbohydrates as their main source
of energy; sometimes used for structural purposes
3.1.1.1.2 Lipids
3.1.1.1.2.1 Can be used to store energy. Some are important parts
of biological membranes and waterproof coverings
3.1.1.1.3 Nucleic Acids
3.1.1.1.3.1 Store and transmit hereditary, or genetic, information
3.1.1.1.4 Proteins
3.1.1.1.4.1 Control rate of reactions and regulate cell processes. Some
form important cellular structures, while still others transport
substances into or out of cells or help fight disease
4 Chemical Reactions and Enzymes
4.1 Chemical Reactions
4.1.1 Process that changes, or transforms,
one set of chemicals into another
4.1.1.1 Chemical reactions involve changes in the
chemical bonds that join atoms in compounds
4.1.1.1.1 Chemical reactions that release
energy often occur on their own
4.1.1.1.2 Chemical reactions that absorb energy
will not occur without a source of energy
4.2 Enzymes
4.2.1 Speed up chemical
reactions that take
place in cells
4.2.1.1 Temperature, pH, and
regulatory molecules
can affect the activity
of enzymes
