Anatomy and Physiology Overview

Anatomy and Physiology

• Anatomy: Studies the structure and parts of the body.
• Physiology: Studies the function and workings of body parts.

Levels of Organization

• Chemical level: Simplest level, involving atoms and molecules.
• Cellular level: Cells are the basic units of life.
• Tissue level: Groups of similar cells form tissues.
• Organ level: Tissues combine to form organs.
• Organ system level: Organs working together form organ systems.
• Organism level: Highest level, encompassing all organ systems.

Characteristics of Life

• Growth: Increase in size and cell number.
• Reproduction: Ability to produce offspring.
• Responsiveness: Reaction to environmental changes.
• Movement: Motion of the body or its parts.
• Metabolism: Chemical reactions providing energy.
• Homeostasis: Maintaining a stable internal environment.

Homeostasis

• Homeostasis: Maintaining a stable internal environment.
• Receptors: Detect changes in internal/external conditions.
• Set point: Normal range or value for a variable.
• Effectors: Organs/tissues that correct deviations from the set point.
• Negative feedback: Reduces or reverses the original stimulus (e.g., body temperature).
• Positive feedback: Amplifies or increases the original stimulus (e.g., childbirth).

Body Divisions

• Axial portion: Head, neck, and trunk.
• Cranial cavity: Houses the brain.
• Spinal cavity: Contains the spinal cord.
• Thoracic cavity: Houses lungs and heart.
• Abdominopelvic cavity: Contains digestive and reproductive organs.
• Appendicular portion: Limbs and connective structures (shoulders, hips).

Body Cavities and Membranes

• Pleural membranes: Line the lungs.
• Pericardial membranes: Surround the heart.
• Peritoneal membranes: Line the abdominal cavity and cover its organs.

Organ Systems

• Integumentary system: Skin, hair, nails; Protection and regulation of temperature.
• Skeletal system: Bones and cartilage; Support and protection of organs.
• Muscular system: Skeletal muscles; Movement.
• Nervous system: Brain, spinal cord, and nerves; Control and coordination.
• Endocrine system: Glands; Hormone production and regulation.
• Cardiovascular system: Heart and blood vessels; Blood circulation.
• Lymphatic system: Lymph nodes and spleen; Immunity.
• Respiratory system: Lungs and trachea; Gas exchange.
• Digestive system: Stomach and intestines; Food breakdown and nutrient absorption.
• Urinary system: Kidneys and bladder; Waste removal and water balance.
• Reproductive system: Ovaries and testes; Reproduction.

Anatomical Position and Terms

• Anatomical position: Standing erect, facing forward, arms at sides, palms forward.
• Superior: Above.
• Inferior: Below.
• Anterior (ventral): Front.
• Posterior (dorsal): Back.
• Medial: Toward the midline.
• Lateral: Away from the midline.
• Bilateral: Both sides.
• Ipsilateral: Same side.
• Proximal: Closer to the point of attachment.
• Distal: Further from the point of attachment.
• Superficial (peripheral): Near the surface.
• Deep: Away from the surface.

Anatomical Sections

• Sagittal section: Divides the body into left and right.
• Transverse section (cross section): Divides the body into upper and lower parts.
• Frontal section (coronal section): Divides the body into front and back parts.
• Cross section: Perpendicular cut.
• Oblique section: Cut at an angle.
• Longitudinal section: Lengthwise cut.

Abdominal Regions and Quadrants

• Nine regions: Right hypochondriac, epigastric, left hypochondriac; Right lumbar, umbilical, left lumbar; Right iliac, hypogastric, left iliac.
• Four quadrants: Right upper quadrant (RUQ), left upper quadrant (LUQ), right lower quadrant (RLQ), left lower quadrant (LLQ).