Overview of Human Physiology

Definition: Study of the functions and mechanisms in the human body.
Focus: How organs and systems work individually and together to maintain homeostasis.

Major Organ Systems

Circulatory System
- Composed of heart, blood vessels, and blood.
- Function: Transport nutrients, gases, hormones, and waste.
- Homeostasis role: Regulates temperature and pH balance.
Respiratory System
- Composed of lungs, trachea, and diaphragm.
- Function: Gas exchange (oxygen in, carbon dioxide out).
- Homeostasis role: Maintains acid-base balance.
Digestive System
- Includes mouth, esophagus, stomach, intestines, liver, and pancreas.
- Function: Breakdown of food for nutrient absorption.
- Homeostasis role: Regulates energy and nutrient levels.
Nervous System
- Composed of brain, spinal cord, and nerves.
- Function: Control and communication network.
- Homeostasis role: Responds to internal and external stimuli.
Endocrine System
- Glands that secrete hormones (e.g., thyroid, adrenal).
- Function: Regulates metabolism, growth, and mood.
- Homeostasis role: Long-term regulation of bodily functions.
Muscular System
- Composed of skeletal, smooth, and cardiac muscles.
- Function: Movement and stability.
- Homeostasis role: Generates heat and maintains posture.
Skeletal System
- Includes bones, cartilage, and ligaments.
- Function: Provides structure and protection.
- Homeostasis role: Stores minerals and produces blood cells.
Immune System
- Composed of white blood cells, lymph nodes, and spleen.
- Function: Defends against pathogens.
- Homeostasis role: Maintains health by preventing infections.
Integumentary System
- Composed of skin, hair, and nails.
- Function: Protects body, regulates temperature.
- Homeostasis role: Barrier to pathogens and fluid loss.
Urinary System
- Includes kidneys, ureters, bladder, and urethra.
- Function: Eliminates waste and regulates electrolytes.
- Homeostasis role: Maintains fluid balance and blood pressure.

Homeostasis

Definition: The process of maintaining a stable internal environment.
Mechanisms:
- Feedback loops (negative and positive).
- Regulatory systems (nervous and endocrine).

Key Concepts

Cellular Physiology: Study of cell functions, including metabolism and communication.
Tissue Types: Epithelial, connective, muscle, and nervous tissues.
Physiological Processes: Examples include metabolism, respiration, and circulation.
Pathophysiology: Study of how physiological processes are altered in disease.

Importance of Human Physiology

Understanding normal function helps diagnose and treat diseases.
Basis for fields like medicine, physical therapy, and sports science.

Overview of Human Physiology

Study of the functions and mechanisms in the human body.
Examines how organs and systems operate to sustain homeostasis.

Major Organ Systems

Circulatory System
- Comprises the heart, blood vessels, and blood.
- Main function is to transport nutrients, gases, hormones, and waste products.
- Regulates temperature and pH balance, contributing to homeostasis.
Respiratory System
- Consists of lungs, trachea, and diaphragm.
- Facilitates gas exchange by taking in oxygen and expelling carbon dioxide.
- Plays a crucial role in maintaining acid-base balance.
Digestive System
- Includes mouth, esophagus, stomach, intestines, liver, and pancreas.
- Responsible for breaking down food to absorb nutrients.
- Regulates energy and nutrient levels for homeostasis.
Nervous System
- Comprised of the brain, spinal cord, and nerves.
- Functions as a control and communication network throughout the body.
- Responds to both internal and external stimuli, aiding homeostasis.
Endocrine System
- Contains glands such as the thyroid and adrenal glands that secrete hormones.
- Regulates metabolism, growth, and mood through hormonal signals.
- Provides long-term regulation of various bodily functions.
Muscular System
- Composed of skeletal, smooth, and cardiac muscles.
- Enables movement and stability of the body.
- Generates heat and maintains posture, playing a role in homeostasis.
Skeletal System
- Includes bones, cartilage, and ligaments.
- Provides structural support and protection for vital organs.
- Stores minerals and produces blood cells, contributing to homeostasis.
Immune System
- Consists of white blood cells, lymph nodes, and the spleen.
- Defends the body against pathogens and infections.
- Maintains health and homeostasis by preventing the spread of disease.
Integumentary System
- Comprised of skin, hair, and nails.
- Protects the body and regulates temperature.
- Acts as a barrier to pathogens and minimizes fluid loss, essential for homeostasis.
Urinary System
- Includes kidneys, ureters, bladder, and urethra.
- Eliminates waste and regulates electrolyte levels.
- Important for maintaining fluid balance and blood pressure.

Homeostasis

Maintaining a stable internal environment crucial for survival.
Utilizes feedback loops (negative and positive) to regulate bodily functions.
Involves nervous and endocrine regulatory systems for effective responses.

Key Concepts

Cellular Physiology: Involves studying how cells carry out functions like metabolism and communication.
Tissue Types: Divided into four main categories: epithelial, connective, muscle, and nervous tissues.
Physiological Processes: Encompasses critical functions such as metabolism, respiration, and circulation.
Pathophysiology: Focuses on alterations in physiological processes due to diseases.

Importance of Human Physiology

Understanding normal body function is essential for diagnosing and treating health issues.
Forms the foundation for disciplines like medicine, physical therapy, and sports science.