Anatomy and Physiology: Organ Systems and Homeostasis

Overview

• Introduction to major concepts from Exercise 2:
  • Organ systems
  • Feedback loops
  • Homeostasis
  • Divisions of the body (cavities and membranes)

Organ Systems

Integumentary System

• Composed of skin, hair, nails
• Functions:
  • Protective barrier
  • Prevents dehydration
  • Vital for Vitamin D formation

Nervous System

• Functions:
  • Detection of stimuli (external & internal)
  • Sensory detection (e.g., heat, color perception)
  • Control of movements
• Components:
  • Brain, spinal cord, neurons, sensory organs

Muscular System

• Functions:
  • Movement generation
  • Heat production due to high metabolic rate

Skeletal System

• Functions:
  • Support and protection for internal organs
  • Provides attachment points for muscles
  • Blood cell production

Circulatory System

• Primarily nutrient and waste transport
• Heart pumps blood through vessels delivering oxygen and glucose

Endocrine System

• Composed of hormone-producing organs and tissues
• Example: Insulin production by the pancreas

Lymphatic System

• Functions:
  • Fluid collection and return
  • Defense against infections

Respiratory System

• Functions:
  • Oxygen intake and distribution
  • Carbon dioxide expulsion

Digestive System

• Functions:
  • Nutrient breakdown and absorption
  • Waste elimination as fecal matter

Urinary System

• Functions:
  • Maintains blood volume and composition
  • Filters waste from blood

Reproductive System

• Male: Hormone and sperm cell production
• Female: Egg and hormone production
• Hormones trigger secondary sex characteristics

Homeostasis and Feedback Loops

Homeostasis

• Maintenance of physiological variables within normal range
• Examples: Blood pressure, blood glucose levels

Feedback Systems

Negative Feedback

• Reverses the original stimulus
• Example: Insulin lowers high blood glucose

Positive Feedback

• Amplifies the original stimulus
• Example: Oxytocin levels increase during childbirth

Body Cavities and Membranes

Body Cavities

• Cranial: Contains the brain
• Vertebral: Runs through the spine
• Thoracic: Contains pleural, pericardial, and superior mediastinal areas
• Abdominopelvic: Includes abdominal and pelvic cavities

Membranes

• Serous Membranes: Line cavities without opening to the outside
  • Pericardial: Around the heart
  • Pleural: Around the lungs
  • Peritoneum: In the abdominopelvic cavity
• Parietal vs. Visceral:
  • Parietal: Lines the cavity walls, most superficial
  • Visceral: Lines the organ surface

Abdominopelvic Divisions

Regions

• Right side: Hypochondriac, Lumbar, Iliac
• Left side: Hypochondriac, Lumbar, Iliac
• Middle: Epigastric, Umbilical, Hypogastric

Quadrants

• Right Upper, Left Upper, Right Lower, Left Lower
• Important to know organ locations within these regions and quadrants

Conclusion

• Overview of major concepts from Exercise 2
• Preparation for quizzes and exams