Appendix A: Chemistry
Elements: materials that cannot be broken down into other materials
Compounds: materials made up of combining materials
Atoms and Molecules:
Atom: a tiny fragment that cannot be broken down any further. Every element if composed of this. It is
composed of subatomic particles (protons, neutrons and electrons) all located in the nucleus of the atom,
electrons found around the space of nucleus. The amount of protons and electrons match so there is a
Molecule: The smallest possible broken down piece that contains the properties of the compound
The difference between the elements is in how many protons are found in the nucleus atomic number
Atomic weight: the weight of an atom relative to the weight of one proton. The proton has the weight of
one unit, neutron has a greater weight than one and electron has weight greater than zero.
Ions and Chemical Bonds
Ions: an atom that has lost one or more electrons
Ionic bond: the attraction of positive ions for negative ions
Covalent bond: when atoms do not transfer electrons from one anther but rather sharing theme between
Reactions of Carbon Atoms
Organic chemistry: the carbon chemistry between living organisms and carbon
Carbon atoms form covalent bonds with a number of different other elements.
C-C: two atoms share one pair of electrons
C=C: two atoms share two pairs of electrons
C≡C: two atoms share three pairs of electrons
Purines and pyrimidine’s (pg. 489) form the central structures of DNA and RNA, which are responsible for
Proteins, fats, and carbohydrates are the primary types of fuels that the body uses.
Chemical Reactions in the Body
Life requires chemical reactions to occur within the body. One chemical reaction produces a chemical that
enters into another reaction, which produces another chemical and so on. If one reaction is too rapid it
can produce a harmful level of that chemical. If too slow, it will not produce enough chemicals and the
next reaction will be stalled.
Enzymes: proteins that control the rate of chemical reactions. Each reaction is controlled by a particular
enzyme; they are like catalysts. A catalyst is any chemical that helps get a reaction from other chemicals
but does not alter itself in the process.
The Role of ATP
Our bodies rely on ATP because it is the main way of sending energy to the rest of the body where it is
needed. i.e.) eating food forms ATP molecules that provide energy for the body and muscles
Chpt. 2 Nerve Cells and Nerve Impulses
Anatomy of Neurons and Glia
Neurons: receive information and transmit it to other cells, the average brain contains around one billion
neurons Santiago Cajal is one of the main founders of neuroscience. He used infant brains and stained some cells
in the brain without affecting the others to examine the structure of a single cell. He found that nerve cells
stay separate instead of merging into one another.
The Structure of an Animal Cell
Membrane: the surface of a cell; structure that separates the inside of the cell from the outside
environment. Composed of two layers of fat molecules that are free to flow around one another. Specific
protein channels in the membrane permit a controlled flow of water, oxygen, sodium, potassium, calcium,
chloride and other important chemicals.
All animal cells have a nucleus (structure containing chromosomes)
Mitochondrion: structure that provides energy