Basic Concepts of Chemistry in Anatomy and Physiology

Importance of Chemistry in Anatomy and Physiology

• Understanding cellular physiology requires knowledge of chemical processes.
• Organs and tissues are composed of cells, whose functions are dictated by chemical interactions.
• Chemistry is foundational for comprehending physiological processes such as digestion, cardiovascular, and nervous systems.

Introduction to Atoms and Molecules

• Atoms: Basic units of matter, composed of protons, neutrons, and electrons.
  • Protons (+), Neutrons (0), Electrons (-)
  • Located: Protons and neutrons in nucleus; electrons in orbits/shells.
• Molecules: Two or more atoms chemically bonded.

Chemical Bonds

• Ionic Bonds: Formed by complete transfer of electrons, creating charged ions (cations and anions).
  • Example: Sodium chloride (NaCl).
• Covalent Bonds: Formed by sharing of electrons.
  • Types: Single, double, triple bonds based on the number of shared electron pairs.
  • Polar and Nonpolar covalent bonds.
  • Examples: Methane (CH₄ - nonpolar), Water (H₂O - polar).
• Hydrogen Bonds: Weak bonds formed between polar molecules via attraction of opposite charges.

States of Matter

• Solid, Liquid, Gas: Different states based on atomic/molecular arrangement and energy.

Energy in Chemistry

• Energy: Capacity to do work, existing as potential (stored) or kinetic (motion).
  • Forms include chemical, electrical, mechanical, radiant.

Elements and Atomic Structure

• Elements: Pure substances composed of one type of atom.
  • Identified by atomic number (number of protons) and mass number (protons + neutrons).
• Periodic Table: Organizes elements by increasing atomic number, indicating chemical properties.
  • Focus on C, O, H, N, Ca, Na, K, Cl, I, Fe for physiology.

Isotopes and Radioisotopes

• Isotopes: Variants of elements with different neutron numbers.
• Radioisotopes: Unstable isotopes emitting radiation, used in medical diagnostics and treatments.

Matter and Mixtures

• Matter: Anything that occupies space and has mass.
• Mixtures: Physical combinations of two or more substances.
  • Types: Solutions (solute + solvent), colloids (gel-like), suspensions (settle out).

Valence Shell & Chemical Reactivity

• Valence Shell: Outermost shell of electrons, determining chemical reactivity.
  • Octet Rule: Stable when filled with 8 electrons (except 1st shell, stable with 2).

Chemical Bonds in Physiology

• Formation and breaking of bonds underpin many physiological processes.
• Understanding chemical interactions assists in grasping complex biological functions.

Next Steps in Learning

• Further exploration into biochemistry.
  • Study of organic and inorganic molecules like carbohydrates, proteins, and lipids.