39145 - Physiology of Organs and Systems

Learning outcomes

To understand and learn the key biophysical principles applied to cell membranes, with a focus on nerve and muscle cells; to understand the basics of human physiology, with a focus on the mechanisms that maintain vital functions.

Course contents

Course introduction: expected learning outcomes, course objectives, recommended textbooks, university IT resources.

Introduction to physiology and its general principles. Negative and positive feedback circuits. Homeostasis. Body fluid compartments. Osmosis, osmolarity, osmotic pressure, and water flow by osmosis. Concepts of amount of substance, molar concentration, osmolar concentration, and tonicity. Subcellular compartments. Cell membrane. Diffusion and its formalization through Fick’s law. Concepts of concentration gradient and net flux. Simple and facilitated diffusion, primary and secondary active transport, transcytosis. Uniport, symport, and antiport.

Concentrations of sodium, potassium, chloride, and bicarbonate ions inside and outside cells. Nernst equation to determine the equilibrium potential of an ion. Reference values of equilibrium potentials for sodium, potassium, and chloride. Membrane conductance equation to determine the resting membrane potential. Sodium-potassium ATPase pump. Concepts of depolarization and hyperpolarization. Action potential. Voltage-gated sodium channels: opening, closing, and inactivation. Voltage-gated potassium channels and after-hyperpolarization. Absolute and relative refractory periods. Chemical and electrical synapses. General overview of neurotransmitters and receptors.

General aspects of blood and its functions. Determinants of ultrafiltration according to Starling equilibrium. Cardiovascular system: general aspects. Cardiac pump. Intrinsic properties of the heart. Blood flow in the cardiac chambers. Cardiac valves. Cardiac conduction system. Action potentials in working myocardium and specialized myocardium.

Electrophysiological basis of the electrocardiogram. Phases of the cardiac cycle. Values of aortic pressure, left ventricular pressure, and left ventricular volume during the cardiac cycle. Definitions of end-systolic volume, end-diastolic volume, stroke volume. Definitions of systolic, diastolic, and pulse pressure. Contribution of arterial elasticity and arteriolar resistance to pulse pressure. Definition and reference values of cardiac output. Poiseuille’s law. Total resistance in systems arranged in series and in parallel. Contribution of different vascular segments to total peripheral resistance.

Principles of arterial pressure measurement using the Riva-Rocci method. Korotkoff sounds. Practical demonstration of the use of a sphygmomanometer and stethoscope for measuring blood pressure. Blood pooling in dependent limbs during standing (orthostatism).

Functional anatomy of the respiratory system. Upper and lower airways. Ventilatory mechanics. Muscles of ventilation. Intrapleural pressure, pneumothorax. Changes in alveolar and pleural pressure during a ventilatory cycle. Direct spirometry. Lung volumes and capacities. Indirect spirometry. Dead space. Pulmonary and alveolar ventilation. Composition of ambient air and gases in the airways and alveoli. Alveolar-capillary gas exchange: alveolar-capillary membrane, partial pressures of oxygen and carbon dioxide in systemic arterial and venous blood. Hemoglobin saturation curve. Role of erythrocytes in carbon dioxide transport.

Functional anatomy of the kidney and nephron. Composition of urine. Glomerular filtration barrier. Glomerular filtration rate. General mechanisms of tubular reabsorption and secretion.

Potassium balance; effects of hyperkalemia and hypokalemia on cellular excitability. General aspects of hormones. Hormones of the neurohypophysis and adenohypophysis.

General aspects of bone tissue: bone matrix and cells. Compact and spongy bone. Periosteum and endosteum. Calcium balance: parathyroid hormone, vitamin D, calcitonin.

Muscle classification: skeletal, cardiac, and smooth muscle. Sarcomeres: M bands, Z lines, thick and thin filaments, contractile proteins (actin, myosin), regulatory proteins (tropomyosin, troponin), structural proteins. Actin-myosin cross-bridge cycle. Excitation-contraction coupling in skeletal muscle: cytoplasmic calcium, dihydropyridine and ryanodine receptors, SERCA pump. Single twitch and tetanic contraction.

Digestive function. General aspects of the motor, secretory, and absorptive functions of the digestive system.

Readings/Bibliography

Zocchi, Principi di Fisiologia. 2020, Edises, Napoli.

Teaching methods

The course is entirely delivered through in-person lectures, supported by electronic slides and video materials. The visual content presented during lectures is mainly taken from the recommended textbooks.

The lectures will be supplemented with review sessions using specific apps.

Practical sessions will be held for small groups of students (measurement of blood pressure).

Assessment methods

The assessment is designed to verify that students have acquired the theoretical knowledge related to the topics presented during the lectures.

The exam is held in written form and consists of 33 true/false questions to be completed within 25 minutes. Each correct answer is worth one point; incorrect answers do not incur any penalty. If a student obtains 18 points, the final grade will be 18; if 19 points are obtained, the final grade will be 19, and so on. If more than 30 points are obtained, the final grade will be 30 with honors (30 cum laude).

During the exam, the use of support materials such as textbooks, notes, or electronic devices is not permitted.

If a student decides to retake the exam, regardless of the outcome, the result of the previous exam will be automatically cancelled.

To pass the integrated course exam and proceed with the official recording of the grade, students must achieve a passing mark in all subjects (biochemistry, biology, anatomy, and physiology) included in the integrated course. The final grade will be calculated as the average of the grades obtained in the individual modules of the integrated course.

Students with learning disabilities or temporary/permanent disabilities are invited to contact the dedicated office (https://site.unibo.it/studenti-con-disabilita-e-dsa/it/per-studenti ) as soon as possible in order to arrange appropriate accommodations. The request must be submitted in advance (at least 15 days before the exam date) to the instructor, who will assess the suitability of the measures, taking into account the learning objectives.

Teaching tools

The visual and textual materials used during lectures are made available to students in electronic format on the website https://iol.unibo.it/ . This material, accessible via username and password, is reserved for UNIBO students.

Office hours

See the website of Chiara Berteotti