3. Applied Learning Outcomes
Use the terminology associated with the
body’s chemical makeup
Learn about:
• Atomic structure and bonding
• Molecular structure
• Characteristics of the biochemical groups
composing the human body
• The chemical environment in which human
biochemicals function
Understand the aging and pathology of the
body’s chemical makeup
Chapter 2 – The Body’s Chemical Makeup
4. Atoms and Molecules
• All organisms are
composed of
energy and matter
• All matter is
composed of
atoms
• Atoms have a
central core called
the nucleus, which
is composed of
protons and
neutrons that
determine the
atomic mass
Chapter 2 – The Body’s Chemical Makeup
5. Acids and Bases
Acid solutions have
a high hydrogen ion
concentration
Base or alkaline
solutions have a low
hydrogen ion
concentration
Chapter 2 – The Body’s Chemical Makeup
6. Human Molecules
The human body is composed of
lipids, carbohydrates, peptides,
and nucleic acids.
Each group has a unique chemistry
that determines its role in the body.
Chapter 2 – The Body’s Chemical Makeup
7. Molecules and Nutrition
The right amounts
of biochemicals
must be absorbed
to maintain
homeostasis.
Chapter 2 – The Body’s Chemical Makeup
8. Wellness and Illness over
the Life Span
• Molecular aging – also called senescence – is
due to the destruction of essential biochemicals.
• The human body is continuously decaying at the
chemical level.
• Factors such as oxidation and exposure to
ultraviolet light can contribute to molecular
decay.
Chapter 2 – The Body’s Chemical Makeup
9. Summary
All organisms are composed of energy and matter.
Matter and energy work together to build and run
the human body.
Elements are bonded together to form a wide array of
structural and functional molecules. Molecules need
a constant supply of energy to carry out their roles.
Humans are primarily composed of organic molecules
called biochemicals. It is necessary to take in
appropriate portions of the biochemicals needed to
replace those that are used up.
Chapter 2 – The Body’s Chemical Makeup
Editor's Notes
The proton number or atomic number determines the properties of an atom. Atoms with a particular proton number are called elements. Elements that vary in neutron number are called isotopes. Ions are elements that have more or fewer electrons than protons and carry an electric charge. Elements can form ionic, covalent, and hydrogen bonds. An isomer is a molecule that has the same elemental makeup, but a different elemental arrangement. Organisms are primarily composed of organic molecules called biochemicals. All biochemicals are composed of a carbon skeleton and a functional group.
pH (the “potential for hydrogen atoms”) is a measure of the hydrogen ion concentration in a solution. pH is represented by the pH scale, which ranges from pH 1 through 14. pH numbers 1 through 6 are acids, 7 is neutral, and bases are pH 8 through 14. Buffers are used in the body to prevent pH fluctuations.
Lipids (or Fats): Simple molecules that provide the body with chemical signals, insulation, padding, and stored energy Carbohydrates: Compound molecules that provide the body with energy Peptides: Linear polymers of amino acids Nucleic Acid: Molecules involved in converting food energy and an essential component of genetic material
In health fields, HOMEOSTASIS implies the natural tendency of a person to maintain physiological and psychological stability; at the molecular level of the body, this means taking in a constant supply of energy and raw materials needed to keep each body component in a continuous state of well-being.
SENESCENCE: The aging process in organisms Functional molecules, such as enzymes, break down as a result of the work they carry out. (Compare to a machine breaking down after years of use.) Structural molecules decay of their own accord, or are destroyed by injury or disease. OXIDATION: The process of joining oxygen with another molecule; a chemical change in which an atom loses an electron – this can prevent many biochemicals from carrying out their natural jobs
