2CENTRAL NERVOUS SYSTEM PERIPHERAL NERVOUS SYSTEM BRAINSPINAL CORDSOMATIC NERVOUS SYSTEMAUTONOMIC NERVOUS SYSTEMSYMPATHETIC NERVOUS SYSTEMPARASYMPATHETIC NERVOUS SYSTEM
3The Nervous SystemNervous system is a delicate and complex communication system made up of billions of connected nerve cells (neurons), transmitting information around our bodyConsists of the brain, spinal cord and nerves throughout our bodiesThere are 2 main subdivisions of the Nervous System- The Central Nervous System (CNS) and the Peripheral Nervous System (PNS)CNS= Brain and Spinal CordPNS= all other nerves in our bodies
5CNS- The BrainKnown as the “Master Organ” because it overseas everything we think, feel and do.Located in the skull and has a wrinkled appearanceCan be subdivided into 3 regions: hindbrain (back), midbrain (middle) and forebrain (front)
6CNS- Spinal Cord The body’s information highway! Complex cable of nerve fibres stretching from the base of the brain to the lower backConnects the brain to other parts of the body through its connection with the PNSReceives sensory information from the PNS and transmits it to the brainTransmits messages (responses) from the brain to the rest of the body (via PNS)
7Neurons (Nerves)Neurons are nerve cells and the basic units involved in all behavioursThey receive and send electrical signals between the CNS and our bodies and also signal between themselves.Sensory (afferent) neurons- carry information from the senses to Interneurons in the CNS for interpretationInterneurons- found only within the CNS and provide the link between sensory and motor neuronsMotor (efferent) neurons- transmit movement messages from Interneurons in the CNS outwards to the muscles and body for action.
8Activity:Copy in your books a diagram of a Neuron and complete the mix n Match worksheet labelling the parts of a neuron.Now build your very own Neuron out of Pipe- Cleaners!
9Peripheral Nervous System (PNS) Peripheral meaning “border”All of the nerves outside the brain and spinal cordCarries messages to and from various muscles, glands and senses throughout the bodyFurther divided into 2 subsections: the Somatic and Autonomic nervous system
10PERIPHERAL NERVOUS SYSTEM SOMATIC NERVOUS SYSTEMAUTONOMIC NERVOUS SYSTEM
11PNS- Somatic Nervous System A branch of the PNS that controls our voluntary movementAlso called the Skeletal Nervous System because it connects the skeletal muscles with the CNS allowing voluntary movementCarries Sensory Information TO the CNSCarries Motor Information FROM the CNSMessages can only travel in one direction, so the PNS has two different pathways for carrying messages to and from the CNS
12PNS- Autonomic Nervous System Carries messages between the CNS and the heart, lungs and other internal organs and glandsThe ANS regulates and controls the functioning of internal organs “automatically”EG- heart rate, breathing, digestion, salivation ectANS functions independently of the CNSHas 2 subdivisions: Sympathetic Nervous System and Parasympathetic Nervous System
13PERIPHERAL NERVOUS SYSTEM AUTONOMIC NERVOUS SYSTEMSYMPATHETIC NERVOUS SYSTEMPARASYMPATHETIC NERVOUS SYSTEM
14Autonomic Nervous System: Sympathetic Nervous System Arouses the body when you are experiencing an extreme emotion or feel threatenedActivates the “fight or flight” responseEg- Bungy Jumping, hearing footsteps in a dark alleyFight: Stay and “fight” the threatening situationFlight: Take “flight” and run away from the situation
15Autonomic Nervous System: Parasympathetic Nervous System Usually the dominant system maintaining a sense of homeostasis (balance) in normal functioning.Calms or restores the body to the normal state of functioning opposite to that of the Sympathetic NSSlow in returning the body back to normal because it takes longer to remove the hormones initially released by the Sympathetic NS for quick action.
16CENTRAL NERVOUS SYSTEM PERIPHERAL NERVOUS SYSTEM BRAINSPINAL CORDSOMATIC NERVOUS SYSTEMAUTONOMIC NERVOUS SYSTEMSYMPATHETIC NERVOUS SYSTEMPARASYMPATHETIC NERVOUS SYSTEM