Nervous System Vocabulary

Flashcards covering key vocabulary terms related to the nervous system, based on provided lecture notes.

Neuron

Consists of several dendrites, single branched axon, and cell body (soma) – cannot divide

Sensory (Afferent) Neuron

Receive initial stimulus from environment

Association (Interneuron)

Receive input from sensory neuron and send to motor neuron –– Make up 99% of the body's neurons

Motor (Efferent) Neuron

From brain, stimulate target cells (effectors) to elicit response

Dendrites

Receive information to transfer to cell body

Axon Hillock

Site of action potential generation

Axon

Transfer impulses away from cell body

Glial Cells

Capable of dividing; include oligodendrocytes, Schwann cells, microglia, ependymal cells, satellite cells, and astrocytes

Oligodendrocytes

Produce myelin in CNS

Schwann cells

Produce myelin in PNS

Microglia

CNS phagocytes

Ependymal cells

Circulate CSF with cilia

Satellite cells

Support cells in PNS

Astrocytes

Physically support CNS neurons; maintain nutrient and mineral balance

Central Nervous System (CNS)

Contains the brain, spinal cord, and interneurons; has a blood-brain barrier

Peripheral Nervous System (PNS)

Utilizes preganglionic/postganglionic axons, various neurotransmitters, and differing receptors to act on the effector organs (targets)

Somatic Nervous System

Innervates skeletal muscle; involved in voluntary or involuntary movements; uses ACh at neuromuscular junctions

Forebrain

Largest part of the brain, including olfactory bulb, thalamus, hypothalamus, basal ganglia, hippocampus, and cerebrum

Limbic system

Includes hippocampus, amygdala, and hypothalamus (behavioral and emotional responses)

Diencephalon

Subdivision of the forebrain including the thalamus, hypothalamus, and pineal gland

Cerebrum

Contains cerebral cortex; divided by frontal, parietal, temporal, and occipital lobes

Frontal lobe

Conscious thought (attention)

Parietal lobe

Sensory; somatosensation, proprioception

Temporal lobe

Sound processing/interpretation

Occipital lobe

Visual input

Sympathetic Branch of Autonomic Nervous System

Fight or flight; increased blood pressure & heart rate, ejaculation, generation of energy; Inhibition of digestion, urination, and salivary secretion

Midbrain

Relay center for visual/auditory impulses; motor control

Hindbrain

Posterior part of the brain, including cerebellum, brainstem, pons, and medulla oblongata

Cerebellum

Balance and coordination

Brainstem

Connects cerebrum to spinal cord; includes midbrain, medulla oblongata, and pons

Pons

Relay center (cortex ↔ cerebellum)

Medulla oblongata

Controls breathing & heart rates, GI activity

Parasympathetic Branch of Autonomic Nervous System

Rest and digest; lowered heart rate; increased digestion, relaxation, and sexual arousal

Na+/K+ Pump

Maintains resting potential of -70 mV using ATP; 3 Na+ out for every 2 K+ in

Sensory Receptors

Respond strongly to their own stimuli and weakly to others; types include mechanoreceptors, thermoreceptors, nociceptors, electromagnetic receptors, and chemoreceptors

Mechanoreceptors

For touch

Thermoreceptors

For temperature

Nociceptors

For pain

Electromagnetic Receptors

For light

Chemoreceptors

For taste, smell, blood chemistry

Acetylcholine (ACh)

Binds to ACh receptors on post-synaptic membrane for nerve transmission; secretion at neuromuscular junctions = contraction or relaxation of muscles (PNS). Recycled back to presynaptic vesicle via acetylcholinesterase

Glutamate

Most common CNS neurotransmitter in vertebrates; excitatory

GABA

Found in brain; inhibitory

Glycine

Found in CNS outside brain; inhibitory

Epinephrine (E) and Norepinephrine (NE)

Act in sympathetic nervous system. E = bronchodilation and vasodilation to lungs and skeletal muscles; vasoconstriction to the digestive system and kidneys