What is a reflex An inborn involuntary and

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

stimulus receptor Processing; Decision to respond effector response Brain

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 muscle Sensory neuron spinal cord interneuron motor 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

Spinal cord interneuron Cell body of Sensory neuron synapse motor neuro 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 Peripheral Nervous System Is divided into two types of neurons called Central N. S. Carry messages to sensory motor Receive messages from sense organs contains Examples include skin eyes ears contains The Somatic N. S. Involved with conscious control of Skeletal muscle Which carry messages to Muscles and glands that control involuntary activities of the body are part of the Autonomic N. S.

Autonomic N. S. Two divisions include Sympathetic N. S. Parasympathetic N. S. produces responses needed for stress produces responses needed for calm

white 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