Introduction to Anatomy & Physiology

Overview

Anatomy and Physiology are foundational sciences in understanding the human body. Anatomy focuses on the structure of body parts, while physiology explores their function and how they work together to sustain life.

• Anatomy: Study of the structure of body parts and their relationships to one another.

• Physiology: Study of the function of body parts; how they work to carry out life-sustaining activities.

Terminology in Anatomy & Physiology

Importance of Terminology

Understanding medical terminology is essential for effective communication in health sciences. Terms are often constructed from prefixes, suffixes, and root words.

Branches of Anatomy

Macroscopic (Gross) Anatomy

Macroscopic anatomy is the study of large, visible structures of the body.

• Regional Anatomy: Examines all structures in a particular area of the body.

• Systemic Anatomy: Studies just one system (e.g., cardiovascular, nervous, muscular).

• Surface Anatomy: Focuses on internal structures as they relate to the overlying skin (e.g., muscles or veins seen on the surface).

Microscopic Anatomy

• Cytology: Microscopic study of cells.

• Histology: Microscopic study of tissues.

Developmental Anatomy

• Developmental Anatomy: Studies anatomical and physiological development throughout life.

• Embryology: Study of developments before birth.

To study anatomy, one must know anatomical terminology and be able to observe, manipulate, palpate, and auscultate.

Branches of Physiology

Types of Physiology

• Organ System Physiology: Focuses on specific organ systems (e.g., renal or cardiovascular physiology).

• Cellular and Molecular Physiology: Examines how the body's abilities are dependent on chemical reactions in individual cells.

Understanding physiology requires knowledge of basic physical principles (e.g., electrical currents, pressure, movement) and basic chemical principles.

Complementarity of Structure and Function

Principle of Complementarity

Structure and function are closely related in the human body. What a structure can do depends on its specific form. This is known as the principle of complementarity of structure and function.

• Example: The sharp edges of incisors (structure) make them ideal for cutting like scissors (function).

Levels of Structural Organization

Hierarchy of Organization

The human body is highly organized, from the smallest chemical level to the entire organism.

• Chemical Level: Atoms combine to form molecules.

• Cellular Level: Cells are made up of molecules.

• Tissue Level: Groups of similar cells form tissues.

• Organ Level: Organs are made up of different types of tissues.

• Organ System Level: Organ systems consist of different organs that work together closely.

• Organismal Level: The human organism is made up of many organ systems.

Necessary Life Functions

Basic Functions Required for Life

All living organisms must perform several essential functions to maintain life:

• Maintaining Boundaries: Separation between internal and external environments (e.g., cell membranes, skin).

• Movement: Includes movement of body parts via skeletal muscles, substances via cardiac and smooth muscle, and movement at the cellular level.

• Responsiveness: Ability to sense and respond to stimuli (e.g., reflexes, changes in breathing rate).

• Digestion: Breakdown of ingested foodstuffs, followed by absorption of simple molecules into the blood.

• Metabolism: All chemical reactions that occur in body cells, including catabolism (breakdown) and anabolism (synthesis).

• Excretion: Removal of wastes from metabolism and digestion (e.g., urea, carbon dioxide, feces).

• Reproduction: At the cellular level, division of cells for growth or repair; at the organismal level, production of offspring.

• Growth: Increase in size of a body part or the organism as a whole.