Nervous System Flashcards
Function of Nervous System
The function of the nervous system is to detect impulses from the senses; control center of the body
Major Organs of Nervous System
Brain
Spinal Cord
Senses
Nerves
Difference between Neurons and Neuroglia
Neurons make up 10% of the nervous system
Neuroglia “nerve-glue”, make up 90% of the nervous system
Dendrite
Receive the nerve impulses from the senses or another neuron
Soma
Body of the neuron that holds the nucleus
Schwann Cells
The main glial cells of the peripheral nervous system which wrap around axons of motor and sensory neurons to form the myelin sheath.
Node of Ranvier
impulses jump from node to node, which increase speed of impulse
Myelin
insulates the axon. Produced by the Schwann cells
Axon
Passageway for nerve impulses after cell body; end in axon terminal.
Axon Terminal
The button-like endings of axons through which axons make contact with other nerve cells.
CSF
The cerebrospinal fluid protects the brain by preventing the it from contacting the skull. It also maintains the blood-brain barrier, which controls homeostasis for the brain and prevents infection.
Cerebrum
Largest part of brain. Divided into 2 hemispheres. Outer cerebral cortex= “gray matter,” made of cell bodies & dendrites. Controls conscious activities. Inner cerebral medulla= “white matter,” made of myelinated axons
Frontal Lobe
Voluntary movements (walking), Reasoning & decision-making, Memory, Ability to predict consequences of actions, Planning, Verbal communication
Parietal Lobe
The parietal lobe controls: Sensations, Visual-spatial processing, Body position
Occipital Lobe
The occipital lobe controls: Visual processing- vision & memory of objects
Temporal Lobe
The temporal lobe controls: Memory, Comprehension & pronunciation of words, Sensations of smell and sound, Emotional association of memories
Thalamus
2 bulb-shaped halves in the center of the brain. Relays sensory impulses to the cerebral cortex for processing and sorting
Hypothalamus
Controls hormones released by pituitary gland (often called the “master endocrine gland”)
Responsible for autonomic processes (body temperature, hunger, sleep, thirst, blood volume, etc)
Brainstem
Located between the cerebrum and spinal cord.
Midbrain
Also known as mesencephalon. Relays info to cerebrum. Controls body movements and postures
Pons
Almost completely made of white matter that links cerebral cortex and cerebellum
Carries info from one side of brain to the other (why its called the bridge)
Central control of breathing
Medulla Oblongata
Located above the spinal cord
Transmits impulses between spinal cord and the brain
Controls blood pressure, heart rate, swallowing, and coughing
Cerebellum
Second largest part of brain, Near back of skull, Responsible for coordinating the movements directed by the cerebrum so that they are graceful and efficient, All involuntary movements, Aids in “muscle memory”
Spinal Cord
Extends from the medulla oblongata. 31 pairs of spinal nerves branch out from the spinal cord, connecting to all parts of the body. Relays impulses from the PNS to the brain.
