Nervous System Flashcards
Function of Nervous System
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 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 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
Cerebrospinal Fluid (CSF)
Protects the brain from making contact with the skull and maintains the blood-brain barrier which controls homeostasis for the brain and prevents infection
Cerebrum
Largest part of the brain; divided into two hemispheres; outer cerebral cortex - “grey matter”, made of cell bodies and dendrites; controls conscious activities; inner cerebral medulla - “white matter”, made of myelinated axons
Frontal Lobe
Voluntary movements; reasoning and decision making, memory; ability to predict consequences of actions; planning; verbal communication
Temporal Lobe
Controls memory; comprehension and pronunciation of words; sensations of smells and sounds; emotional association of memories
Parietal Lobe
Controls sensations; visual-spatial processing; body position
Occipital Lobe
Controls visual processing; vision; memory of objects
Thalamus
Relays sensory impulses to the cerebral cortex for processing and sorting
Hypothalamus
Controls hormones released by the pituitary gland; responsible for autonomic processes (body temperature, hunger, sleep, thirst, blood volume, etc.)
Brainstem
Located between the cerebrum and spinal cord, broken into three sections
(Brainstem) Midbrain
Also known as mesencephalon; relays info the cerebrum; controls body movements and postures
(Brainstem) Pons
Also known as the bridge; almost completely made of white matter that links cerebral cortex and cerebellum; carries info from one side of the brain to the other; central control of breathing
(Brainstem) Medulla Oblongata
Located above the spinal cord; transmits impulses between the spinal cord and the brain; controls blood pressure, heart rate, swallowing, and coughing
Cerebellum
Second largest part of the 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 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; a cross-section of the spinal cord has a “butterfly” of grey matter surrounded by white matter