Nervous System Flashcards
Functions of Nervous System
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 is “nerve glue” and makes 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
allows myelin sheets to grow
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
Cerebrospinal Fluid meant to protect the brain from hitting the skull
Cerebrum
Largest part of brain, Divided into 2 hemispheres
Gray and White Matter
Controls conscious activities
Frontal Lobe
voluntary movement, reasons and decision making, memory, ability to predict consequences of actions, planning, verbal communication
Parietal Lobe
sensations, visual-spatial processing, body position
Occipital Lobe
Visual processing- vision & memory of objects
Temporal Lobe
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 that
relays sensory impulses to the cerebral cortex for processing and sorting
Hypothalamus
Controls hormones released by pituitary gland and responsible for autonomic processes (body temperature, hunger, sleep, thirst, blood volume, etc)
Brainstem
Located between the cerebrum and spinal cord
Midbrain
Relays info to cerebrum and controls body movements and postures
Pons
The Bridge! 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, A cross section of the spinal cord has a “butterfly” of gray matter surrounded by white matter
Merkel’s Disk
touch
Hair Follicle Receptor
touch
Ruffini’s Corpuscle
touch and pressure
Pacinian Corpuscle
pressure
Free Nerve Ending
pain and temperature
Papillae
bumps on the tongue that contain taste buds that contain chemoreceptors
Malleus
Hammer
Incus
Anvil
Stapes
Stirrup
Cochlea
A bony snail shaped structure containing membranes filled with fluid
Cornea
Made of thick transparent tissue, allows light into the eye
Pupil
The opening in the center of the iris, muscles regulate the amount of light entering the eye
Low light- pupil wide open
High light- pupil nearly closed
Iris
located behind the cornea, colored part of the eye, works with pupil to regulate light entering the eye
Retina
located in the back of the eye, contains thousands of photoreceptors such as rods and cones
Lens
a semi-solid disc that directs light waves towards the retina
Nearsighted vs Farsighted
In farsightedness the eyeball is too short and in nearsightedness the eyeball is too long
