When we talk about autoregulation, it's not the blood pressure we are talking about but it's rather the blood flow over a changing pressure which is being regulated. In terms of hemodynamics, the flow across a blood vessel is determined by the pressure gradient across...
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CVS Physiology Lecture # 19 Study Notes: Autonomic Control of Nodal Action Potential
The autonomic control of nodal action potentials refers to the regulation of the electrical activity in the specialized cardiac cells known as nodal cells, particularly in the sinoatrial (SA) node and the atrioventricular (AV) node, by the autonomic nervous system. This intricate control mechanism, facilitated by the sympathetic and parasympathetic divisions of the autonomic nervous system, plays a critical role in modulating heart rate and cardiac function.
Study Notes Lecture # 7: Development of Inferior Vena Cava
The inferior vena cava (IVC) is a major vein in the human body that carries deoxygenated blood from the lower body to the right atrium of the heart. During embryonic development, the IVC forms as a result of the fusion of several paired veins, including the common iliac veins and the lumbar veins.
Study Notes Lecture # 8: Histology of Blood Vessels
The histology of blood vessels involves the microscopic study of the structure and composition of different types of blood vessels, including arteries, veins, and capillaries. Arteries are characterized by their thick, muscular walls comprising three layers: the tunica intima, tunica media, and tunica externa. The tunica intima is composed of endothelial cells supported by a thin layer of connective tissue.
Lecture # 3 Study Notes: Ventricles and Aorticopulmonary Septum
The ventricles and aorticopulmonary septum are essential components of the human heart, working in concert to facilitate the circulatory system’s efficient functioning. Understanding their structure and function provides insights into the complex mechanics of the cardiac system.
Lecture # 4 Study Notes: Pharyngeal Arch Arteries
The pharyngeal arch arteries are a series of embryonic vascular structures that contribute to the development of the major arteries in the head and neck. During early development, six pairs of these arteries form in a sequential manner within the pharyngeal arches.
Lecture # 2 Study Notes: Atrial Development & Congenital Defects
Atrial development is a crucial process during embryogenesis, involving the formation of the two upper chambers of the heart, the right atrium, and the left atrium. These chambers play a fundamental role in receiving deoxygenated blood from the body and oxygenated blood from the lungs, respectively. Congenital defects related to atrial development are abnormalities that occur during the embryonic stages, leading to structural malformations in the atrial septum.
Lecture # 1 Study Notes: Heart Tubes
Heart tubes, critical in the early stages of embryonic development, are the primitive structures that later give rise to the complex organ, the heart. Emerging during the third week of gestation, these rudimentary tubes undergo a series of intricate morphological changes, leading to the formation of the four-chambered heart. The transformation from a simple linear structure to a sophisticated, functional pump involves a complex interplay of genetic, molecular, and mechanical cues.
Lecture # 6 Study Notes: Fetal Circulation and Shunts
Fetal circulation refers to the unique circulatory system present in a developing fetus. This system is distinct from the postnatal circulatory system and is crucial for the proper development of the fetus during gestation. Fetal circulation is characterized by specific shunts and structures that enable the redirection of blood flow to bypass certain non-functioning organs and facilitate the exchange of gases and nutrients between the fetus and the mother.
Lecture # 3 Study Notes: Conduction System of the Heart
The conduction system of the heart controls the electrical impulses that regulate the heartbeat. It consists of specialized cardiac tissues, including the sinoatrial (SA) node, atrioventricular (AV) node, bundle of His, and Purkinje fibers.