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Human Anatomy and Physiology II. Introduction. Topics. Autonomic nervous system Endocrinology Cardiovascular physiology Immunology Respiratory physiology Renal physiology Digestion Reproductive physiology. Homeostasis. Homeostasis. Claude Bernard’s concept All organs interact
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Human Anatomy and Physiology II Introduction
Topics • Autonomic nervous system • Endocrinology • Cardiovascular physiology • Immunology • Respiratory physiology • Renal physiology • Digestion • Reproductive physiology
Homeostasis Claude Bernard’s concept All organs interact All cells of organs bathed in internal fluid Cells exist if fluid remains constant in quantity and quality (osmosis) Fluctuations occur within narrow limits
Feedback mechanisms Disturbance Negative feedback - Control system Sensor Error signal Inverted amplifier Set point adjustment
Negative feedback • Beneficiale.g. perspiration • Disturbance (increase in body temp.) • Sensor (nervous system) • Inverted amplifier (decrease in temp.) • Doesn’t prevent displacement • Restores stability close to operating parameters (set point adjustment)
Feedback mechanisms Disturbance Positive feedback + Signal Control system Sensor Amplifier Output
Positive feedback • Rare • Mostly destructivee.g. congestive heart failure • Disturbance (inability of heart to pump blood) • Sensor (nervous system) • Amplifier (increase in heart muscle contraction, further impeding pumping ability)
Control systems Stimulus Response Receptor (cell) Integration (CNS) Effector (muscle, gland) Afferent Efferent