Chapter 1: An Introduction to Anatomy and Physiology

Key Concepts

This chapter introduces the foundational principles of anatomy and physiology, including the organization of the human body, essential terminology, and the concept of homeostasis.

• Anatomy and Physiology: Anatomy is the study of body structures, while physiology is the study of how those structures function. These disciplines are closely integrated, with structure determining function (principle of complementarity).

• Levels of Organization: The human body is organized from the simplest to the most complex: chemical, cellular, tissue, organ, organ system, and organism levels.

• Medical Terminology: Understanding word roots, prefixes, and suffixes is crucial for comprehending anatomical and physiological terms. Eponyms are often replaced by more precise terms.

• Anatomical Terminology: Standard terms are used to describe body regions, sections, and relative positions (e.g., anatomical position, supine, prone, abdominopelvic quadrants/regions, sectional planes like frontal, sagittal, and transverse).

• Body Cavities: Fluid-filled spaces protect organs and allow for changes in their size and shape. Major cavities include the thoracic cavity (pleural and pericardial cavities, mediastinum) and the abdominopelvic cavity (abdominal and pelvic cavities, peritoneal cavity).

• Homeostasis: The body's ability to maintain a stable internal environment. This involves homeostatic regulation through autoregulation (local response) and extrinsic regulation (nervous and endocrine systems). A homeostatic regulatory mechanism includes a receptor, control center, and effector.

Vocabulary List

• Anatomy: Study of internal and external body structures and their physical relationships among other body parts.

• Physiology: Study of how living organisms perform their vital functions.

• Principle of complementarity of structure and function: All specific functions are performed by specific structures, and the form of a structure relates to its function.

• Surface anatomy: Anatomy of body surface.

• Regional anatomy: Anatomy of specific body areas.

• Sectional anatomy: Understanding the relationship of body structures by examining cross sections.

• Systemic anatomy: Anatomy of organ systems.

• Clinical anatomy: Anatomy as used in clinical practice.

• Pathological anatomy: Anatomical changes during illness.

• Radiologic anatomy: Anatomical structures seen using imaging techniques.

• Surgical anatomy: Anatomical landmarks important in surgery.

• Developmental anatomy: Anatomical changes from fertilization to adulthood.

• Embryology: Study of early developmental processes.

• Cytology: Study of the structure of cells.

• Histology: Study of the structure of tissues.

• Cell physiology: Study of the function of cells and their chemical processes.

• Organ physiology: Study of the function of specific organs.

• Systemic physiology: Study of function of organ systems.

• Pathological physiology: Study of effects of diseases on organs or systems.

• Signs: Objective disease indications (such as a fever).

• Symptoms: Subjective disease indications (such as tiredness).

Levels of Organization

The human body is organized into hierarchical levels, each with increasing complexity.

• Chemical level: Atoms and molecules.

• Cellular level: Cells, the basic unit of life.

• Tissue level: Groups of similar cells performing a common function.

• Organ level: Two or more tissues working together.

• Organ system level: Groups of organs interacting for a particular function.

• Organism level: An individual life form.

Medical Terminology and Anatomical Reference

Precise terminology is essential for clear communication in anatomy and physiology.

• Medical terminology: Involves using word roots, prefixes, suffixes, and combining forms to build terms related to the body in health and disease.

• Eponyms: Commemorative names (such as names based on names of discoverer of a structure or disease).

• Anatomical position: Standard anatomical reference position with hands at the sides, palms facing forward and feet together.

• Anterior view: Body in anatomical position from the front.

• Posterior view: Body in anatomical position from the back.

• Supine: Body lying face up.

• Prone: Body lying face down.

Body Regions, Planes, and Cavities

Body regions and planes are used to describe locations and sections in anatomical study.

• Abdominopelvic quadrants: Divide the abdominopelvic region in four quadrants.

• Abdominopelvic regions: Divide the abdominopelvic region in nine specific regions.

• Section: A slice through a three-dimensional object.

• Sectional plane: A single view or slice along a two-dimensional flat surface.

• Frontal (coronal) plane: A vertical plane that divides the body or organ into anterior and posterior portions.

• Sagittal plane: A vertical plane that divides the body or organ into left and right portions.

• Midsagittal plane: Lies in the middle of the sagittal plane.

• Parasagittal plane: Offset from the middle of the sagittal plane.

• Transverse (horizontal) plane: A horizontal plane that divides the body or organ into superior and inferior portions.

• Body cavities: Closed, fluid-filled cavities that are lined by a thin serous membrane; contain the vital organs (viscera) of the trunk.

Major Body Cavities and Membranes

Homeostasis and Regulation

Homeostasis is the continuous physiological process that maintains a relatively stable internal environment.

• Homeostatic regulation: The adjustment of physiological systems to preserve homeostasis.

• Autoregulation: Automatic, local response to an environmental change in a cell, tissue, or organ.

• Extrinsic regulation: Responses of organ systems controlled by the nervous system (through electrical signals) or the endocrine system (through chemical messengers).

• Receptor: A sensor that detects the stimulus or change.

• Control center: Processes the information and sends out commands.

• Effector: Responds to the commands and opposes or enhances the stimulus.

Chapter 2: The Chemical Level of Organization

Key Concepts

This chapter explores the chemical basis of life, including atomic structure, chemical bonds, and reactions essential for cellular function.

• Atoms and Atomic Structure: Matter is composed of atoms, which consist of subatomic particles (protons, neutrons, electrons). The atomic number defines an element, and isotopes are variations with different numbers of neutrons. Electrons occupy shells, and the valence shell determines chemical reactivity.

• Molecules and Compounds: Atoms combine to form molecules and compounds through chemical bonds. These include ionic bonds (transfer of electrons, forming ions), covalent bonds (sharing of electrons), and hydrogen bonds (weak attractions between polar molecules).

• Chemical Reactions: These involve the formation or breaking of chemical bonds. Types include decomposition reactions (catabolism, release energy), synthesis reactions (anabolism, consume energy), and exchange reactions. Many biological reactions are reversible and seek equilibrium.

• Enzymes: Biological catalysts that speed up biochemical reactions by lowering the activation energy without being consumed in the process.

Vocabulary List

• Chemistry: The science that deals with the structure of matter.

• Matter: Anything that takes up space and has mass.

• Atom: The smallest stable unit of matter.

• Subatomic particles: Protons, neutrons, and electrons.

• Protons: Positively charged particles found in the nucleus.

• Neutrons: Neutral particles found in the nucleus.

• Electrons: Negatively charged particles that orbit the nucleus.

• Electron shell: Two-dimensional representation of an electron cloud.

• Element: A pure substance composed of atoms of one kind, which cannot be broken down into simpler substances by ordinary physical means.

• Isotopes: Versions of an element that have different numbers of neutrons.

• Mass number: The number of protons plus the number of neutrons of an atom.

• Radioisotopes: Isotopes that have unstable or radioactive nuclei.

• Radioactive decay: The breakdown of the nucleus of a radioisotope.

• Half-life: The time required for half of a given amount of isotope to decay.

• Atomic weight: An average of the different atomic masses and proportions of different isotopes.

• Atomic mass: The actual mass of an atom, taking into account the masses of its protons, neutrons and electrons.

• Mole (mol): A specific quantity that has a weight in grams equal to the atomic weight of the element.

• Avogadro's number: The number of atoms in one mole of a given element.

• Valence shell: The outermost electron shell, determining the chemical properties of an element.

• Inert elements: Elements with a full valence shell that are not reactive.

• Chemical reactions: Result in the formation of new bonds or the breaking of existing bonds.

• Molecule: Two or more atoms joined by shared electrons.

• Compound: Two or more atoms of different elements.

• Molecular weight: The sum of the atomic weights of its atoms.

Chemical Bonds and Reactions

Chemical bonds hold atoms together and determine the properties of molecules.

• Covalent bonds: Strong bonds created when atoms share electrons.

• Single covalent bond: Sharing one pair of electrons.

• Double covalent bond: Sharing two pairs of electrons.

• Triple covalent bond: Sharing three pairs of electrons.

• Nonpolar covalent bonds: Equal sharing of electrons between two atoms.

• Polar covalent bonds: Unequal sharing of electrons between two atoms.

• Polar molecules: Molecules in which one side is partially positive and the other partially negative due to unequal sharing of electrons.

• Hydrogen bonds: Weak electrical attractions between the partial positive charge of a hydrogen atom in a polar covalent bond and the partial negative charge of an atom of oxygen, nitrogen or fluorine in another polar covalent bond.

States of Matter

• Solid

• Liquid

• Gas

Chemical Reactions

• Reactants: The reacting substances that enter a chemical reaction.

• Products: The resulting substances at the end of a chemical reaction.

• Metabolism: All chemical reactions that are occurring in the cells and tissues of the body at any given time.

• Work: The movement of an object or a change in the physical structure of matter.

• Energy: The capacity to do work.

• Kinetic energy: The energy of motion.

• Potential energy: Stored energy an object possesses because of its position or its physical or chemical structure.

• Decomposition reactions: Break molecules into smaller fragments.

• Hydrolysis reactions: Decomposition reactions which involve water.

Important Equations

• Mass number:

• Mole:

Enzymes and Activation Energy

Enzymes are biological catalysts that lower the activation energy required for chemical reactions, increasing the rate of reaction without being consumed.

• Activation energy: The minimum amount of energy required to start a chemical reaction.

• Enzyme: A protein that speeds up chemical reactions by lowering activation energy.

Example Table: Types of Chemical Bonds

Additional info:

• Some terms and definitions have been expanded for clarity and completeness.

• Tables have been recreated and summarized for comparison and classification purposes.