Anatomy and Physiology Overview

Anatomy

• The study of the structure and shape of the body and its parts
• Divided into two major types: gross anatomy and microscopic anatomy
• Gross anatomy studies large body structures visible to the naked eye
  • Divided into three subcategories:
    • Surface anatomy studies external anatomical features without dissection
    • Regional anatomy focuses on specific regions of the body and how systems work together in those regions
    • Systemic anatomy focuses on the anatomy of different organ systems
• Microscopic anatomy studies structures too small to be seen without magnification
  • Includes two important topics:
    • Cytology studies the structure and function of cells
    • Histology studies the organization and details of tissues

Physiology

• The study of how the body and its parts function
• Inseparable from anatomy, as structure determines function
• Example: the thin walls of the lungs allow for gas exchange, while the muscular heart pumps blood

Levels of Structural Organization

• The human body demonstrates structural complexity from the simplest to the most complex level
• Chemical level: Atoms combine to form molecules like water, sugar, and proteins
• Cellular level: Molecules associate to form cells, the smallest units of living things
• Tissue level: Groups of similar cells with a common function
  • Four basic tissue types: epithelial, connective, muscular, and nervous
• Organ level: Composed of two or more tissue types working together for a specific function
• Organ system level: A group of organs working together to accomplish a common purpose
• Organismal level: The highest level of structural organization, the sum total of all structural levels working together to sustain life

Eleven Major Organ Systems

• The human body is made up of 11 organ systems
• Integumentary system: Includes skin, hair, and fingernails
  • Protects deeper tissues, waterproofs the body, produces vitamin D, excretes salts, helps regulate temperature, contains sensory receptors
• Skeletal system: Composed of bones, cartilages, and joints
  • Supports the body, provides framework for movement, protects organs, produces blood cells, stores minerals
• Muscular system: Contains muscles, responsible for movement
  • Skeletal muscles for movement of the body as a whole, other muscles for movement of fluids and substances within the body
• Nervous system: Includes brain, spinal cord, nerves, and sensory receptors
  • Rapid-acting control system, responds to stimuli, detects changes, assesses information, activates effectors (muscles or glands)
• Endocrine system: Consists of glands that produce hormones
  • Regulates body activities more slowly than nervous system, hormones released into blood and travel to target organs
  • Controls growth, reproduction, use of nutrients by cells
• Cardiovascular system: Includes heart and blood vessels
  • Delivers oxygen, nutrients, hormones, picks up wastes, transports blood to all tissues
• Lymphatic system: Includes lymphatic vessels, lymph nodes, spleen, tonsils
  • Returns fluid to bloodstream, cleanses blood, houses immune cells
• Respiratory system: Includes nasal passages, pharynx, larynx, trachea, bronchi, lungs
  • Supplies body with oxygen, removes carbon dioxide
• Digestive system: Includes mouth, esophagus, stomach, small and large intestines, rectum, accessory organs
  • Breaks down food, delivers nutrients to blood, reabsorbs water, eliminates waste
• Urinary system: Removes waste by-products from the body

This quiz covers the foundational concepts of anatomy and physiology, including the differences between gross and microscopic anatomy. Explore the subcategories of gross anatomy such as surface, regional, and systemic anatomy, as well as the functions of cells and tissues in microscopic anatomy. Test your knowledge on how structure influences function in the human body.