Anatomy and Physiology basics

Overview of Anatomy and Physiology

• Anatomy studies the structure of the body parts and their relationships.
• Gross or macroscopic anatomy examines large, visible structures.
• Microscopic anatomy looks at structures at a cellular level.
• Developmental anatomy studies structural changes throughout life, embryology studies changes before birth.
• Physiology studies the function of the body's structures.

Microscopic Anatomy

• Cytology is the study of cells.
• Histology is the study of tissues.

Levels of Structural Organization

• Chemical level: atoms combine to form molecules.
• Cellular level: cells are made of molecules.
• Tissue level: similar types of cells form tissue.
• Organ level: different types of tissues make up an organ.
• Organ system level: different organs working together form an organ system.
• Organismal level: organ systems combine to create an organism.

Organ Systems

• The Integumentary System forms the body covering, composed of skin, sweat, and oil glands, hair, and nails, protecting tissues and synthesizing vitamin D.
• The Skeletal System, including bones, cartilage, and ligaments, protects and supports organs, provides muscle frameworks, forms blood cells, and stores minerals.
• The Muscular System, consisting of muscles and tendons, facilitates manipulation, locomotion, facial expression, maintains posture, and produces heat.
• The Nervous System, including the brain, spinal column, and nerves, is the body's fast-acting control system, responding to stimuli using muscles/glands.
• The Cardiovascular System is composed of the heart and blood vessels; it pumps and transports blood throughout the body.
• The Lymphatic System comprises red bone marrow, the thymus, the spleen, lymph nodes, and vessels; it collects fluid leaked from blood vessels, disposes of debris, and is involved in immunity with white blood cells.
• The Respiratory System which includes the nasal cavity, pharynx, trachea, bronchi, and lungs supplies blood with oxygen and removes carbon dioxide.
• The Digestive System which includes the oral cavity, esophagus, stomach, and intestines breaks down food for absorption and eliminates waste.
• The Urinary System composed of kidneys, ureters, the bladder, and the urethra eliminates nitrogenous waste and regulates the balance of water, electrolytes, and pH.
• The Male Reproductive System includes the prostate, penis, testes, and scrotum and is responsible for producing offspring.
• The Female Reproductive System which includes mammary glands, ovaries, uterine tubes, uterus, and the vagina is responsible for producing offspring.

Organ Systems Interrelationships

• The integumentary system protects the body from the external environment.
• The digestive and respiratory systems take in nutrients and oxygen from the external environment.
• Nutrients and oxygen are distributed by the blood.
• Metabolic wastes are eliminated by the urinary and respiratory systems.

Necessary Life Functions

• Maintaining boundaries keeps the internal environment distinct.
• Cellular level is maintained by plasma membranes.
• Organismal level is maintained by the skin.
• Movement includes locomotion and propulsion.
• Responsiveness is the ability to sense and respond to environmental changes.
• Digestion involves breaking down ingested food.
• Metabolism includes all chemical reactions within the body.
• Excretion releases waste from the body.
• Reproduction occurs at cellular and organismal levels; cellular reproduction and organismal reproduction of sperm and egg.
• Growth increases the size of a body part or the whole organism.

Survival Needs

• Nutrients are needed for energy and cell building.
• Oxygen is necessary for metabolic reactions.
• Water creates the environment for chemical reactions.
• Normal body temperature is necessary for sustaining life.
• Atmospheric pressure is required for breathing and gas exchange.

Anatomical Position

• Position consists of the body being erect, feet slightly apart, palms facing forward, with thumbs pointing away from the body.

Directional Terms

• Superior (cranial) refers to structures toward the head or upper part of the body.
• Inferior (caudal) refers to structures away from the head or toward the lower part of the body.
• Ventral (anterior) refers to structures toward the front of the body.
• Dorsal (posterior) refers to structures toward the back of the body.
• Medial refers to structures toward the midline of the body, on the inner side.
• Lateral refers to structures away from the midline of the body, on the outer side.
• Intermediate refers to a structure in between a more medial and a more lateral structure.
• Proximal indicates nearness to the origin of the body part or connection point of a limb on the body's trunk.
• Distal indicates distance from the origin of the body part or the connection point of a limb on the body's trunk.
• Superficial (external) refers to nearness to the body's surface.
• Deep (internal) refers to moving away from the the bodies surface.

Body Planes

• Sagittal divides the body into right and left parts.
• Midsagittal or medial is a sagittal plane on the midline.
• Frontal or coronal divides the body into anterior and posterior parts.
• Transverse or horizontal divides the body into superior and inferior parts.
• Oblique section cuts made diagonally.

Body Cavities

• Dorsal cavity protects the nervous system, divided into cranial cavity and vertebral cavity.
• The cranial cavity encases the brain.
• The vertebral cavity encases the spinal cord.
• Ventral cavity houses internal organs and is divided into thoracic and abdominopelvic cavities.

Ventral Body Cavity Subdivisions

• Thoracic cavity consists of plural cavities, mediastinum, and pericaridal cavity.
  • Each pleural cavities houses a lung.
  • Mediastinum consists of the pericardal cavity and surrounds the thoracic organ.
  • Pericardal cavity surrounds the heart.
• Abdominopelvic cavity separated by the diaphragm, divided into abdominal and pelvic cavities.
  • Abdominal cavity contains stomach, intestines, spleen, liver, and other organs.
  • Pelvic cavity contains the bladder, reproductive organs, and rectum.

Ventral Body Cavity Membranes

• Parietal serosa lines internal body walls.
• Visceral serosa covers internal organs.
• Serous fluid separates the serosae.

Other Body Cavities

• Oral and digestive cavities are the mouth and cavities of the digestive organs.
• Nasal cavity is located within and posterior to the nose.
• Orbital cavities house the eyes.
• Middle ear cavity contains bones that transmit sound vibrations.
• Synovial cavity is joint cavities.

Abdominopelvic Regions

• Right hypochondriac region.
• Epigastric region.
• Left hypochondriac region.
• Right lumbar region.
• Umbilical region.
• Left lumbar region.
• Right iliac region.
• Hypogastric region.
• Left iliac region.

Abdominopelvic Quadrants

• Right Upper Quadrant
• Left Upper Quadrant
• Right Lower Quadrant
• Left Lower Quadrant