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TRANSCRIPT
Chapters 11-14
Describe the anatomy, histology, and physiology of the central and peripheral nervous systems and name the major divisions of the nervous system.
Identify the parts of a reflex arc.
Describe signal transmission across a myoneural junction.
Identify the major functions associated with the sympathetic and parasympathetic nervous systems.
Identify the major parts of a cross section through the spinal cord.
Identify the functions of the major parts of the brain, including the meninges, medulla, pons, midbrain, hypothalamus, thalamus, cerebellum and cerebrum.
Control and communication center of the body
Sensory input Integration Motor output
Central Nervous System (CNS) • Spinal cord and brain • Integration & command center
Peripheral Nervous System (PNS)
• Paired spinal and cranial nerves • Carries messages to and from the CNS
CNS
Red is CNS
Blue is PNS
Divided into 2 divisions:
Afferent division • Sensory • Receptors (eye/ear) send info to CNS
Efferent division
• Motor response • Effectors – something happens (movement)
Somatic nervous system (SNS) • Conscious control of skeletal muscles • Voluntary
Autonomic nervous system (ANS)
• Regulates smooth muscle, cardiac muscle, and glandular secretions
• Subconscious
2 divisions: Parasympathetic:
• Dominates during rest • Maintenance activities
Sympathetic
• Preparation of energetic/stressful activity • “fight or flight”
Basic functional unit of the nervous system
Composed of a cell body, axon, and dendrites
Structural • Mutlipolar • Bipolar • Unipolar
Functional
• Sensory (afferent) • Motor (efferent) • Interneurons (associated
neurons)
~45 cm long ~14mm wide 31 segments
Provide physical stability and shock absorption
3 layers: • Dura mater • Arachnoid mater • Pia mater
Outermost covering of the spinal cord
Middle layer
Between dura mater and arachnoid mater is the subarachnoid space • Where cerebrospinal fluid (CSF)
is Shock absorber Medium for dissolved gases,
nutrients, chemical messengers, and waste products Where spinal taps take place
Innermost layer
Made of elastic and collagen fibers
Bound to underlying neural tissue
31 pairs
Rapid, automatic responses to specific stimuli
5 steps in a reflex arc: 1. Arrival of stimulus and activation of
receptor 2. Activation of a sensory neuron 3. Information processing in CNS 4. Activation of a motor neuron 5. Response by effector
Postural reflex • Maintain a normal upright posture
Tendon reflex • Monitors tension, prevents breaking of
tendon Withdrawal reflex
• Moves parts away from a stimulus Plantar reflex
• Toes curling
Cerebrum Cerebellum Diencephalon Mesencephalon Pons Medulla oblongata
Where conscious thought and intelligent functions originate
Frontal lobe • Voluntary control of skeletal muscle
Parietal lobe • Conscious perception of touch, pressure,
pain, vibration, taste, and temperature Occipital lobe
• Conscious perception of visual stimuli Temporal lobe
• Conscious perception of auditory and olfactory stimuli
Adjusts the postural muscles of the body
Fine tune muscle control
Epithalamus • Contains pineal gland which
secretes melatonin Regulates day/night cycles
Hypothalamus • Controls
autonomic/subconscious functions
• Secretes hormones • Produces emotions
Thalamus
Relates visual/auditory information to produce reflexes
Helps control respiration
Links cerebellum with the brain stem, cerebrum, and spinal cord
Connects brain and spinal cord Center for the coordination of
autonomic functions Controls visceral functions