Week 3 Homeostasis & Feedback Mechanism PDF

Nervous System Working Together with Endocrine System to Maintain Homeostasis Review Endocrine System The endocrine system is a series of glands that produce and secrete hormones that the body uses for a wide range of functions. Review Review...

Nervous System Working Together with Endocrine System to Maintain Homeostasis Review Endocrine System The endocrine system is a series of glands that produce and secrete hormones that the body uses for a wide range of functions. Review Review Nervous System The nervous system works as communication system of the body. It connects all your body parts and transmits signals from one part to another. Sends, receives and process information throughout the body and from the environment. Brain Nerves Spinal Cord Review Review Nerve Cell = Neuron Parts of the Neuron Dendrite- Receives information and passes it to the cell body Cell Body- Location of nucleus and organelles Axon- Single portion that carries information away from cell body Review 3 Types of Neurons Parts of the Neuron Sensory Neuron – receives information. Interneuron – processes information (Brain and spinal cord) Motor Neuron – cause action in muscles or glands. Make things “move”  Nervous System & Endocrine System The endocrine system is a chemical control system. It functions in conjunction with the nervous system to control the internal environment (homeostasis).  Nervous System vs. Endocrine System Nervous System Endocrine System Chemical Messenger neurotransmitters hormone Location of message synapses Target cells Effects rapid & short-lasting slower & longer lasting Controls Muscles and glands Activities of the cells  What is Homeostasis? Homeostasis is the state of steady internal, physical, and chemical conditions maintained by living organisms. Homeostasis is the state reached when each part of the body functions in equilibrium with other parts.  Feedback Mechanism A form of regulation wherein the body detects a change in internal environment & responds to the change. Negative Feedback Positive Feedback Positive feedback involves a response Involves a response that is the that reinforce the change detected, reverse of the change detected. simply it functions to amplify the Most common mechanism for change. homeostasis. The results of the process stop the Positive feedback mechanism is a process from continuing (self- process in which the end products of limiting). an action cause more of that action to Maintains conditions within a certain occur in a feedback loop. range Feedback Mechanism Negative Feedback Thermoregulation When the body gets too warm: – blood vessels dilate – sweat is produced – cools body – dilation & sweating stops Negative Feedback Osmoregulation Negative Feedback Regulating Blood Sugar (glucose) When blood sugar is high: – Insulin is released into blood – Causes cells to absorb glucose & liver to store excess glucose – Blood sugar level falls – Insulin levels drop – Which causes liver to release glucose – Which causes insulin to be released into blood, etc Positive Feedback Giving Birth Action of OXYTOCIN on uterine muscle during birth. Baby pushes on cervix Nervous signal to Hypothalamus Hypothalamus manufactures OXY OXY transported to POSTERIOR PITUITARY & released OXY stimulates uterine contraction Loop stops when baby leaves birth canal Positive Feedback Lactation Suckling by infant stimulates sensory neurons in nipple Nerve impulse reaches hypothalamus (brain) Impulse from hypothalamus trigger release of oxytocin Oxytocin stimulates mammary glands to secrete milk Triggers more suckling Positive Feedback Lactation Hormones at Right Level  Achieving Homeostasis Amount of Body Temperature Amount of water in metabolic waste in the body the cell  Achieving Homeostasis Blood calcium level Hormones in the blood THANK YOU