70 likes | 195 Views
Homeostasis. Homeostasis. The process of maintaining the body’s internal environment, despite changes in the external environment This makes sure that the body’s organs and cells are operating at ideal conditions, and thus are most efficient. Factors that are regulated.
E N D
Homeostasis • The process of maintaining the body’s internal environment, despite changes in the external environment • This makes sure that the body’s organs and cells are operating at ideal conditions, and thus are most efficient
Factors that are regulated • Things regulated include: • Blood pressure • Blood pH • Body temperature • Water levels • Blood glucose levels • Heart rate • Respiratory rate
Homeostasis continued • Also called dynamic equilibrium because small changes are constantly occurring • All homeostatic control systems have: • A monitor (sensors that detect imbalance) • Coordinating center (relays information) • Receptor (works to restore balance) • These systems of control are called feedback loops
Negative Feedback Loop • Mechanisms that work to restore the system to normal levels • Negative feedback ensures that small changes do not get too large • Ex. When body temperature rises, you begin to sweat in order to lower temperature • The more common type of feedback loop
Positive Feedback Loop • When the change in a system causes the system to amplify the change • Less common • Ex. During childbirth, as the baby moves towards the cervix, more oxytocin is released, which increases contractions.
Thermoregulation • The maintaining of body temperature • Ectotherms (fish, amphibians, reptiles) depend on the air to regulate body temperature • Endotherms (mammals and birds) maintain a constant body temperature via internal systems • Normal body temperature in humans = 37°C • Hypothalamus acts as the ‘thermostat’