Transcript biochemistry

BIOCHEMISTRY
The chemical
basis of life
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ATOMS
• Basic unit of matter
• Two regions
• Nucleus
• Electron cloud
• Atomic particles
• Protons =
• Positively charged particles
• Located in the nucleus
• Neutrons =
• Neutral particles
• Located in the nucleus & act as the glue there
• Electrons =
• Negatively charged particles
• Located in the electron cloud
• These are the particles involved in chemical reactions
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Elements & Isotopes
• Elements
• Contain all of the same type of atom
within the element
• Elements of Life
• 96%  Carbon (C), Hydrogen (H), Oxygen (O),
and Nitrogen (N)
• 3%  P, S, Ca, K, Na, Mg, Fe, Cl
• 1%  other trace elements
• Isotopes
• Elements that contain a different number of
neutrons
• Radioactive isotopes will breakdown at a
specific rate and are used in figuring the age
of different things (i.e. fossils & rocks)
3
Periodic Table of
Elements
4
Horizontal rows and
Vertical columns
• Horizontal rows on the periodic
table are called periods
• Vertical columns are called
families (or groups)
5
Atomic number vs.
atomic mass
• Atomic number = the number of
protons
• Atomic mass = the number of
protons and
neutrons
6
pH and Buffers
• The pH of substances ranges from 014
• 7 = neutral
• 0-6.9 = acid
• 7.1-14 = base
• Buffers
• Prevent sharp, sudden changes in pH so
that the body can maintain homeostasis
• pH of most fluids in the body = 6.5-7.5
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