BIOL1993 Lecture Notes - Lecture 9: Medulla Oblongata, Lymphatic Vessel, Autonomic Nervous System
Lecture 9 – Research and data base
Lecture 10 – The circulatory system
Cardiovascular system
• Heart
• Blood vessels
Lymphatic system
• Spleen, thymus, tonsils
• Lymphatic vessels
Functions of cardiovascular system
• Supply of material to body tissues
o Nutrients
o Oxygen
o Hormones
• Removal of metabolic waste products
o Ammonia, urea
o Toxins
o Carbon dioxide
Heart anatomy
• Chambers
o Atria
o Ventricles
• Valves
o Atrioventricular valves
o Semilunar valves
Explain how the heart functions
• Cardiac cycle: events associated with blood flow through the heart in one heartbeat
o Systole: contraction period
o Diastole: relaxation period
• Heart is 2 pumps
o Right side to pulmonary circuit
o Left side to systemic circuit
Coordinated contraction of atria
and ventricles controlled by
electrical impulses
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Regulation of cardiac output
• Adjusts the amount of oxygen and nutrients delivered to tissues
• Intrinsic: mechanisms within the heart
• Extrinsic: mechanisms external to the heart
o Autonomic nervous system control
o Cadioregulatory centres in medulla oblongata (autonomic)
Sympathetic activity e.g. in danger
Blood vessels: arteries and arterioles
• Carry blood away from the heart
• Largest and most elastic arteries near the heart
• Arterioles: smallest arteries, regulate blood flow into capillaries
Blood vessels: veins and venules
• Carry blood to the heart
• Large lumens and thin walls
• Blood under low pressure
• Blood flow facilitated by massaging effect of skeletal muscle
• Backflow prevented by valves
Blood vessels: capillaries
• Form network between arterial and venous circulations
• One cell thick
• Thin walls facilitate diffusion
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find more resources at oneclass.com
Document Summary
Lymphatic system: spleen, thymus, tonsils, lymphatic vessels. Functions of cardiovascular system: supply of material to body tissues, nutrients, oxygen, hormones, removal of metabolic waste products, ammonia, urea, toxins, carbon dioxide. Heart anatomy: chambers, atria, ventricles, valves, atrioventricular valves, semilunar valves. Explain how the heart functions: cardiac cycle: events associated with blood flow through the heart in one heartbeat, systole: contraction period, diastole: relaxation period. Coordinated contraction of atria and ventricles controlled by electrical impulses: heart is 2 pumps, right side to pulmonary circuit, left side to systemic circuit. Regulation of cardiac output: adjusts the amount of oxygen and nutrients delivered to tissues. Intrinsic: mechanisms within the heart: extrinsic: mechanisms external to the heart, autonomic nervous system control, cadioregulatory centres in medulla oblongata (autonomic) Blood vessels: arteries and arterioles: carry blood away from the heart, largest and most elastic arteries near the heart, arterioles: smallest arteries, regulate blood flow into capillaries.