Homeostasis and Cellular Response Cheat Sheet

Homeostasis is the body's ability to maintain stable internal conditions essential for survival. Cellular responses adapt to aging, injury, and genetic factors, influencing overall health.

Core Principles

• Homeostasis maintains optimal physiological conditions (temperature, fluids, pH).
• Body fluids are divided into intracellular (ICF) and extracellular (ECF) compartments.
• Water movement is governed by osmotic, oncotic, and hydrostatic pressures.
• Hormones like ADH and aldosterone regulate fluid and electrolyte balance.
• Acid-base balance is maintained by buffers, lungs, and kidneys.
• Cellular responses include adaptation to aging, injury, and genetic mutations.
• Immunity involves innate (immediate, nonspecific) and adaptive (specific, memory) responses.
• Inflammation is a defense mechanism involving vasodilation, increased permeability, and leukocyte migration.
• Genetic disorders arise from DNA mutations, affecting protein synthesis and cellular function.
• CRISPR is a gene-editing technology with ethical considerations.
• Musculoskeletal system integrity relies on bone remodeling and hormonal regulation.
• The integumentary system (skin) provides barrier protection and regulates temperature.
• Neurologic system disorders can affect the CNS or PNS, often due to vascular issues.
• Cardiovascular disorders involve hypertension, atherosclerosis, and heart rhythm disturbances.
• Respiratory system function relies on ventilation and gas exchange; diseases impair these processes.
• Gastrointestinal disorders affect digestion, absorption, and elimination.
• Renal system disorders impair filtration, reabsorption, and waste excretion.
• Endocrine system disorders result from hormonal imbalances affecting metabolism, growth, and reproduction.
• Reproductive system disorders can impact sexual function, fertility, and lead to cancers.

Action Steps

• Monitor fluid and electrolyte balance closely.
• Maintain acid-base balance through diet and lifestyle.
• Understand genetic predispositions and seek genetic counseling.
• Practice sun safety to prevent skin cancer.
• Manage chronic conditions like diabetes and hypertension to prevent neurologic complications.
• Adopt a heart-healthy lifestyle to prevent cardiovascular disease.
• Avoid smoking and environmental toxins to protect respiratory health.
• Maintain a balanced diet for optimal gastrointestinal function.
• Stay hydrated and monitor kidney function.
• Ensure adequate hormone levels through a healthy lifestyle and medical management.
• Practice safe sex to prevent reproductive infections.

Formulas

• $Anion Gap = Na^+ - (Cl^- + HCO_3^-)$

Key Terms

• Homeostasis: The body's ability to maintain stable internal conditions necessary for survival.
• Edema: Swelling caused by excess fluid accumulation in tissues.
• ADH: Antidiuretic hormone; regulates water retention by the kidneys.
• Aldosterone: Hormone that regulates sodium and water retention and potassium excretion.
• RAAS: Renin-Angiotensin-Aldosterone System; regulates blood pressure and fluid balance.
• pH: Measure of acidity or alkalinity; normal blood pH is 7.35-7.45.
• Buffers: Substances that resist changes in pH.
• Innate Immunity: The body's first line of defense; immediate and nonspecific.
• Adaptive Immunity: Specific immune response that develops memory.
• Inflammation: A localized protective response to injury or infection.
• CRISPR: A gene-editing technology for precise DNA modification.
• Fracture: A break in a bone.
• Osteoporosis: Reduced bone density leading to increased fracture risk.
• Stroke: Disruption of blood supply to the brain.
• Atherosclerosis: Hardening and narrowing of arteries due to plaque buildup.
• Pneumonia: Infection of the lungs' air sacs (alveoli).
• GERD: Gastroesophageal reflux disease; acid reflux into the esophagus.
• Glomerulonephritis: Inflammation of the kidney's filtering units (glomeruli).
• Diabetes Mellitus: A group of diseases characterized by high blood glucose levels.
• PID: Pelvic Inflammatory Disease; infection of female reproductive organs.

Timeline

• Ancient Greece: Hippocrates describes the concept of 'vis medicatrix naturae' (healing power of nature), an early precursor to homeostasis.
• 1878: Claude Bernard introduces the concept of the 'milieu intérieur' (internal environment), laying groundwork for homeostasis.
• 1929: Walter Cannon coins the term 'homeostasis' and further defines its principles.
• Mid-20th Century: Development of understanding in genetics, leading to gene therapy concepts and technologies like CRISPR.
• Late 20th Century - Present: Advancements in understanding cardiovascular diseases, leading to new treatments for hypertension, atherosclerosis, and heart failure.
• Early 21st Century: Increased focus on personalized medicine, including genetic testing and targeted therapies for various diseases.

People

• Claude Bernard: Physiologist who introduced the concept of the 'milieu intérieur'.
• Walter Cannon: Physiologist who coined the term 'homeostasis'.
• Gregor Mendel: Father of genetics, whose work on inheritance patterns is foundational.
• James Watson & Francis Crick: Discovered the double-helix structure of DNA.
• Emmanuelle Charpentier & Jennifer Doudna: Pioneers of CRISPR-Cas9 gene editing technology.