Circulatory System Course

Lesson 1 • Blood Composition and Properties

Covers cellular and plasma components of blood and their roles. Connects blood composition to transport and defence functions.

Lesson 2 • Overview of Circulatory System Components

Introduces the heart, blood vessels, and blood as the three pillars of circulation. Sets the structural framework for all subsequent chapters.

Lesson 3 • Basic Haemodynamic Concepts

Introduces pressure, flow, and resistance as governing principles of blood movement. Provides the quantitative foundation for understanding circulation.

Lesson 1 • Myocardial Layers and Wall Thickness

Compares endocardium, myocardium, and epicardium in terms of composition and thickness. Relates wall thickness to workload demands of each chamber.

Lesson 2 • Cardiac Valves and Their Function

Describes atrioventricular and semilunar valves, their leaflets, and supporting structures. Links valve mechanics to unidirectional blood flow.

Lesson 3 • Internal Chambers and Septa

Details the four chambers, interatrial septum, and interventricular septum. Explains how septal structures prevent blood mixing between circuits.

Lesson 4 • External Heart Anatomy

Examines the pericardium, epicardium, and surface landmarks of the heart. Establishes spatial orientation for internal anatomy study.

Lesson 1 • Heart Sounds and Murmurs

Identifies the origin of S1 and S2 sounds and conditions producing extra sounds. Connects abnormal sounds to structural or functional valve pathology.

Lesson 2 • Electrical Conduction System

Traces impulse generation from the sinoatrial node through the ventricular conduction network. Establishes the electrical basis for coordinated contraction.

Lesson 3 • Phases of the Cardiac Cycle

Sequences systole and diastole into discrete phases with corresponding pressure changes. Connects each phase to valve opening and closing events.

Lesson 1 • Vascular Tone and Regulation

Covers neural, hormonal, and local mechanisms controlling vessel diameter. Connects vasoconstriction and vasodilation to blood pressure and flow distribution.

Lesson 2 • Arterial Wall Structure and Classification

Compares elastic, muscular, and arteriolar arteries by tunica composition and diameter. Links structural differences to pressure-dampening and resistance functions.

Lesson 3 • Venous Structure and Return Mechanisms

Examines thin-walled venous anatomy, valves, and capacitance function. Identifies mechanisms that drive venous return against gravity.

Lesson 1 • Baroreceptor Reflex Pathway

Traces the arterial baroreceptor reflex arc from stretch receptors to effector responses. Explains rapid pressure correction within seconds of a disturbance.

Lesson 2 • Integrated Responses to Hypotension

Synthesises neural, hormonal, and renal responses activated during acute blood pressure drops. Demonstrates how multiple systems converge to restore perfusion.

Lesson 3 • Renal Pressure-Natriuresis Mechanism

Explains how the kidney adjusts urine output in response to arterial pressure changes. Establishes renal regulation as the dominant long-term pressure controller.

Lesson 1 • Transcapillary Fluid Dynamics

Applies Starling forces to predict net filtration and reabsorption across capillary walls. Identifies conditions that shift the balance toward oedema.

Lesson 2 • Lymphatic Vessel Structure and Function

Covers lymphatic capillary anatomy, collecting vessels, and lymph node positioning. Explains how lymph is propelled centrally and returned to venous circulation.

Lesson 3 • Oedema: Causes and Clinical Significance

Categorises oedema by mechanism—hydrostatic, oncotic, lymphatic, and inflammatory. Connects each type to recognisable clinical presentations.

Lesson 1 • Cardiovascular Response to Exercise

Quantifies changes in cardiac output, heart rate, and vascular resistance during physical activity. Distinguishes acute responses from chronic training adaptations.

Lesson 2 • Cerebral Circulation and Autoregulation

Describes the cerebral arterial supply, blood-brain barrier, and pressure autoregulation range. Explains why cerebral perfusion is tightly protected.

Lesson 3 • Fetal and Neonatal Circulation

Traces fetal shunts—foramen ovale, ductus arteriosus, and ductus venosus—and their closure at birth. Explains the circulatory transition from placental to pulmonary gas exchange.

Lesson 4 • Pulmonary Circulation Characteristics

Contrasts pulmonary with systemic circulation in pressure, resistance, and flow distribution. Explains hypoxic pulmonary vasoconstriction as a unique regulatory feature.

Lesson 1 • Atherosclerosis and Ischaemic Disease

Traces atherosclerotic plaque development from endothelial injury to luminal obstruction. Links plaque rupture to acute coronary syndromes and myocardial infarction.

Lesson 2 • Clinical Cardiovascular Assessment

Covers non-invasive assessment tools including pulse examination, blood pressure measurement, and electrocardiography. Connects each tool to specific haemodynamic or electrical information.

Lesson 3 • Shock: Types and Haemodynamic Profiles

Classifies hypovolaemic, cardiogenic, distributive, and obstructive shock by haemodynamic signatures. Applies circulatory physiology to explain each type's treatment rationale.

Lesson 4 • Hypertension: Mechanisms and Consequences

Distinguishes primary from secondary hypertension by underlying mechanisms. Connects sustained elevated pressure to target organ damage in heart, kidney, and brain.