Introduction to Human Anatomy and Physiology

Introduction to Human Anatomy and Physiology

• Human anatomy studies the body's structure and relationships between parts.
• Human physiology examines the body's functions and processes.
• Structure and function are connected; understanding one benefits understanding the other.

Levels of Organization

• Chemical level: atoms form molecules.
• Cellular level: molecules form cells, the fundamental unit of life.
• Tissue level: similar cells form tissues.
• Organ level: different tissues combine to create organs.
• Organ system level: multiple organs work together in organ systems.
• Organism level: all organ systems function together as a whole organism.

Anatomical Terminology

• Anatomical position: body erect, facing forward, arms at sides, palms forward.
• Directional terms: describe relative locations. Examples include superior (above), inferior (below), anterior (front), posterior (back), medial (toward midline), lateral (away from midline), proximal (closer to point of attachment), distal (farther from point of attachment), superficial (closer to surface), deep (further from surface).
• Regional terms: name body areas (e.g., cephalic - head, thoracic - chest, abdominal - abdomen).
• Body planes: imaginary surfaces dividing the body (sagittal - left/right, frontal - anterior/posterior, transverse - superior/inferior).

Body Cavities

• Dorsal cavity: houses the brain and spinal cord.
• Ventral cavity: houses internal organs; it's divided into thoracic and abdominopelvic cavities.
• Thoracic cavity: contains the heart and lungs.
• Abdominopelvic cavity: includes the stomach, intestines, and other abdominal and pelvic organs.

Major Tissue Types

• Epithelial tissue: covers surfaces, lines cavities, forms glands. Functions include protection, secretion, absorption, and excretion.
• Connective tissue: supports and connects tissues. Examples include bone, cartilage, blood, and adipose tissue. Functions include support, protection, insulation, and transportation.
• Muscular tissue: responsible for movement. Types include skeletal, smooth, and cardiac muscle.
• Nervous tissue: responsible for communication and control, composed of neurons and supporting cells. Functions include receiving sensory information, coordinating responses, and maintaining homeostasis.

Homeostasis

• Homeostasis: the body's maintenance of a stable internal environment. Variables regulated include temperature, blood glucose, and blood pressure.
• Homeostasis is maintained through feedback loops (positive and negative).

Integumentary System

• Components: skin, hair, nails, sebaceous and sudoriferous glands.
• Functions: protection, thermoregulation, sensation, excretion, vitamin D production.

Skeletal System

• Components: bones, cartilage, ligaments.
• Functions: support, protection, movement, mineral storage, blood cell production.

Muscular System

• Components: skeletal muscles.
• Functions: movement, posture, generates heat.

Nervous System

• Components: brain, spinal cord, nerves, sensory receptors.
• Functions: control and coordination of body activities, sensory input, integration, and motor output.

Endocrine System

• Components: glands (pineal, pituitary, thyroid, parathyroid, adrenal, pancreas, ovaries, testes).
• Functions: regulation of body activities through hormones.

Cardiovascular System

• Components: heart, blood vessels (arteries, veins, capillaries), blood.
• Functions: transport nutrients, oxygen, wastes, hormones, regulate temperature, protect against disease.

Lymphatic System

• Components: lymph vessels, lymph nodes, spleen, thymus.
• Functions: fluid balance, immunity.

Respiratory System

• Components: lungs, air passages.
• Functions: gas exchange (oxygen and carbon dioxide).

Digestive System

• Components: mouth, esophagus, stomach, intestines, liver, gallbladder, pancreas.
• Functions: breakdown and absorption of nutrients.

Urinary System

• Components: kidneys, ureters, urinary bladder, urethra.
• Functions: remove wastes from blood, maintain water and electrolyte balance.

Reproductive System

• Components: male and female reproductive organs.
• Functions: reproduction.

General Organization of the Body

• Organization by body region (head, neck, trunk).
• Body cavities (dorsal and ventral cavities and subdivisions).

Anatomical Imaging Techniques

• Radiography (X-rays): visualize structures with differing densities.
• Computed tomography (CT): multiple X-rays for cross-sectional images.
• Magnetic resonance imaging (MRI): uses magnetic fields and radio waves for detailed soft tissue images.
• Ultrasound: uses sound waves to create images of internal structures.