Chapter 49: Nervous Systems Flashcards
Ganglia
Segmental,y arranged clusters of neurons
What kind of nervous systems to cnidarians have?
Nerve net
What kind of nervous system do Annelida have?
Ganglia
CNS in vertebrates
Brain and spinal cord
PNS in vertebrates
Nerves and ganglia
During embryonic development, where does the central nervous system develop from?
Hollow dorsal nerve cord: gives rise to central canal of spinal cord and ventricles of brain, fill with cerebrospinal fluid
Gray matter
Neuron cell bodies, dendrites, unmyelinated axons, glia
White matter
Bundled axons with myelin sheaths: lies outside of spinal cord to link CNS with NS; primarily on inside of brain for neuron signaling and learning
Glia
Supporting cells in the nervous system
Astrocytes
Facilitate info transfer at synapses, increase blood flow to neurons
Oligodendrocytes
Myelinate axons in CNS
Schwann cells
Myelinate axons in PNS
Microglia
Immune cells that protect against pathogens
Motor system
Consists of neurons that carry signals to skeletal muscles, voluntary or involuntary
Autonomic nervous system
Involuntary: sympathetic, parasympathetic, and enteric
Enteric division of autonomic nervous system
Active in digestive tract, pancreas, gall bladder, to regulate secretion and peristalsis
What brain areas control arousal and sleep?
Brainstem and cerebrum
Arousal and sleep are controlled by what?
Reticular formation: diffuse network of neurons in the core of the brainstem
What does the reticular formation do?
Determines which incoming information reaches the cerebrum
Which centers cause sleep?
Pons and medulla
Where is the center for arousal?
Midbrain
What secretion peaks at night and controls the sleep cycles?
Melatonin
What is the SCN?
Suprachiasmatic nucleus: neurons in the hypothalamus that coordinate circadian rhythms
What is the pacemaker that synchronizes the biological clock?
Supcrachiasmatic nucleus
What are some brain structures that control emotion?
Amygdala, hippocampus, parts of thalamus
What is the limbic system?
Structures that border the brainstem, controls emotion and motivation and olfaction, behavior, memory
What role does the amygdala play in emotional memory storage?
Most important: located near base of cerebrum
What are the three main areas of the brain?
Fore, mid, hind
The mid and hind brain give rise to what?
Brainstem: joins with spinal cord
The rest of the hindbrain gives rise to what?
Cerebellum, lies behind brainstem
The forebrain develops into what?
Diencephalon, including neuroendocrine tissues of brain, telencephalon that becomes the cerebrum
What is the cerebral cortex used for?
Perception, voluntary movement, learning
Corpus callosum
Enables communication between right and left hemispheres
Basal nuclei
Centers for planning and learning movement sequences: deep within white matter
Cerebrum controls?
Skeletal muscle contraction, center for learning, emotion, memory, perception
Cerebellum controls?
Movement, balance, learning, remembering motor skills
Diencephalon controls?
Thalamus, hypothalamus, epithalamus
Thalamus
Main input center for sensory info
Hypothalamus
Body’s thermostats and biological clock, regulates hunger and thirst, role in sexual mating behavior, controls fight or flight
Epithalamus
Includes pineal gland for melatonin
What makes up the brain stem?
Midbrain, pons, medulla oblongata
What does the midbrain do?
Receives and integrates sensory info and sends it to specific regions of the brain
Major function of pons and medulla?
Transfer info between PNS and midbrain and forebrain
