Why are reflexes important? What is a reflex? An inborn, involuntary, and automatic response to a specific stimulus Why are reflexes important? They protect the body – maintain homeostasis
What are some examples of reflexes? blinking pupil constricts in light knee-jerk gag swallowing Vomiting Startle withdrawl Primitive reflexes – in infants – rooting, sucking
receptor effector response Processing; Decision to respond stimulus Brain effector response
Types of Neurons sensory neurons - transmit impulses from the receptors to the spinal cord and brain interneurons - relay impulses between sensory and motor neurons or between other interneurons motor neurons - transmit impulses from the spinal cord to the effectors
Nerve - a bundle of neurons or the axons and/or dendrites of neurons covered with connective tissue
Types of Nerves sensory nerves contain the long dendrites of sensory neurons; transmit impulses away from receptors to the spinal cord and brain motor nerves contain the long axons of motor neurons; transmit impulses from the central nervous system to the effectors
mixed nerves contains both the long dendrites of sensory neurons and the long axons of motor neurons
brain spinal cord muscle interneuron motor neuron Sensory neuron stimulus Label: stimulus, sensory neuron, interneuron, motor neuron, muscle, brain, spinal cord
Reflex Arc - pathway over which impulses travel in a reflex interneuron sensory neuron motor neuron effector stimulus response
Cell body of Sensory neuron interneuron Spinal cord Cell body of Sensory neuron interneuron synapse motor neuron Sensory neuron stimulus muscle
brain spinal cord relays impulses between the brain and the rest of the nervous system; coordinates simple reflexes
Types of Neurons sensory neurons - transmit impulses from the receptors to the spinal cord and brain interneurons - relay impulses between sensory and motor neurons or between other interneurons motor neurons - transmit impulses from the spinal cord to the effectors
Human Nervous System
ganglia - groups of cell bodies (cytons) and interneurons that switch, relay, and coordinate nerve impulses
Peripheral nerves
Eyes
The Central N.S. Peripheral Nervous System Carry messages to Is divided into two types of neurons called sensory motor Which carry messages to contains contains Receive messages from The Somatic N.S. Muscles and glands sense organs Involved with conscious control of that control involuntary activities of the body are part of the Examples include skin eyes ears Skeletal muscle Autonomic N.S.
Autonomic N.S. Two divisions include Sympathetic N.S. Parasympathetic N.S. produces responses needed for produces responses needed for stress calm
white grey cerebrum cerebellum medulla Spinal cord Central Nervous System grey Spinal cord cerebrum cerebellum medulla
Organize these terms in a concept map: from general (top) to specific (bottom) Autonomic Nervous system Central Nervous System Human Nervous System Brain Sympathetic Nervous System Parasympathetic Nervous System Somatic Nervous System Peripheral Nervous System Spinal Cord
Human Nervous System
How would a gymnast use the following during a performance? Cerebrum Cerebellum Medulla Spinal Cord Somatic Nervous System