Introduction to Human Physiology

• Physiology is the study of how living organisms function, encompassing mechanical, physical, and biochemical processes.
• It explores how cells, tissues, organs, and systems work individually and together to maintain life.
• Physiology seeks to understand the normal functions of the body and the mechanisms that regulate these functions.
• The field is crucial for understanding health and disease.

Human Physiology

• Human physiology specifically focuses on the functions and mechanisms of the human body.
• It investigates how different organ systems, such as the cardiovascular, respiratory, and nervous systems, operate and interact.
• It covers topics such as:
  • Cellular and molecular physiology
  • Organ system physiology
  • Integrative physiology
• Understanding human physiology is foundational to medicine and healthcare.
• Homeostasis, the maintenance of a stable internal environment, is a central concept.
• Feedback loops (negative and positive) regulate physiological processes to maintain homeostasis.
• Examples include:
  • Regulation of body temperature
  • Control of blood glucose levels
  • Maintenance of blood pressure

Exercise Physiology

• Exercise physiology examines the effects of physical activity on the body.
• It looks at both acute (immediate) and chronic (long-term) responses to exercise.
• Key areas of study:
  • Cardiovascular responses to exercise (e.g., heart rate, stroke volume, blood flow)
  • Respiratory responses to exercise (e.g., ventilation rate, oxygen consumption)
  • Metabolic responses to exercise (e.g., energy expenditure, substrate utilization)
  • Endocrine responses to exercise (e.g., hormone release)
  • Musculoskeletal adaptations to training (e.g., muscle hypertrophy, increased bone density)
• It informs training programs for athletes and exercise prescriptions for improving health.
• It helps understand how exercise can prevent and manage chronic diseases.
• Training adaptations improve physiological function and performance.

Pathophysiology

• Pathophysiology is the study of how disease disrupts normal physiological processes.
• It explores the mechanisms by which diseases develop and progress.
• Key concepts:
  • Etiology (the cause of disease)
  • Pathogenesis (the sequence of events leading to disease)
  • Clinical manifestations (the signs and symptoms of disease)
• It integrates basic science knowledge with clinical medicine.
• It provides a basis for understanding the diagnosis, treatment, and prevention of diseases.
• It examines alterations in cellular and organ function that occur with disease states.
• Examples include:
  • Diabetes mellitus (disruption of glucose metabolism)
  • Hypertension (abnormal regulation of blood pressure)
  • Asthma (airway inflammation and obstruction)

Neurophysiology

• Neurophysiology is the study of the nervous system's function.
• It examines the electrical and chemical processes that underlie neuronal activity.
• Key areas of study:
  • Action potentials and synaptic transmission
  • Sensory transduction
  • Motor control
  • Brain function and cognition
• Techniques such as electroencephalography (EEG) and nerve conduction studies are used.
• It provides insights into neurological disorders such as epilepsy, Parkinson's disease, and multiple sclerosis.
• The nervous system is responsible for:
  • Receiving sensory information
  • Processing information
  • Coordinating responses

Cell Physiology

• Cell physiology focuses on the functions of individual cells.
• It explores how cells maintain homeostasis, communicate with each other, and perform specialized tasks.
• Key topics include:
  • Membrane transport (e.g., diffusion, osmosis, active transport)
  • Cell signaling (e.g., receptors, signal transduction pathways)
  • Cell metabolism (e.g., glycolysis, oxidative phosphorylation)
  • Cell growth and differentiation
  • Cellular respiration and energy production
• Understanding cell physiology is fundamental to understanding the function of tissues and organs.
• It provides insights into diseases that arise from cellular dysfunction.
• Examples include:
  • Cystic fibrosis (defective chloride transport)
  • Cancer (uncontrolled cell growth)