Human Nervous System Flashcards
What is a neurone?
A nerve cell that is specialised for transmitting signals throughout the nervous system; contains a cell body, axon and dendrites.
What are the three major types of neurone?
Sensory (afferent) neuron
motor (efferent) neuron
associative neuron (interneuron)
What are the three types of nerve tissue and their location?
sensory: connects brain and spinal cord with sensory organs.
Motor: connects brain and spinal cord with muscles and glands.
Associative: within brain and spinal cord.
What are Sensory neuron’s?
They transmit impulses from a sensory receptor to the brain or spinal cord.
What are motor neuron?
The transmit impulses from the brain or spinal cord to muscles or glands.
What are associative Neuron (interneurons)?
That make connection between all types of neurone; found in the brain and spinal cord.
What are Dendrites?
Cytoplasmic extension (usually short) of a neurone; they receive impulses and conduct them inward toward the cell body.
What is the cell body (of a neurone)
Contain the nucleus of the nerve cell.
What are axons?
Long ectoplasmic extension that conducts impulses away from the neurone cell body onward the terminal branches where the impulse will be transmitted.
What is the termini branch of an axon?
It is the transmitting (to another nerve or muscle tissue) at the end of the nerve cell.
What are synapse?
the space between a neurone and another neurone or muscle cell. In drawing impulse is moving left to right. Terminal branches of one nerve cell pass a message to dendrites of another nerve cell.
What are acetylcholine?
A neurotransmitter released across a synapse in order to transmit a nerve impulse.
Describe the center of the spinal cord?
A butterfly-shaped mass of fray matter (contains cell bodies of neurone and synapses) surrounded by white matter (contains axons of neurons).
What is the central nervous system?
The brain the spinal cord; coordinates activity in all parts of the body.
What are the three main areas of the brain?
the cerebrum
the cerebellum
the medulla
What are the five basic sense organs?
Eyes ears nose mouth skin
What is the Cerebrum?
Largest part of the brain; occupies upper part of the skill and is responsible for thought, memory sensation and voluntary movement.
What is the cerebellum?
The region of the brain responsible for balance and coordination of muscles.
What is the Medulla Oblongata?
The most posterior portion of the brain; controls involuntary functions such as breathing; heart rate and certain reflexes.
What is the function of the spinal cord?
It is a pathway for impulses to and from the brain; centre of reflex actions.
What is the autonomic nervous system?
The division of the nervous system that regulates involuntary internal functions such as heartbeat, body temperature, kidney action etc.
What is the sympathetic Nervous system?
The part of the autonomic nervous system that activates the “fight or flight” response.
What is the parasympathetic nervous system.
The part of the autonomic nervous system that slows down the “fight or flight” response in order for the body to rest.
What are ganglia?
A mass of cytons (cell bodies) and synapses lactated on the sides of the backbone; part of the autonomic nervous system.
What is the hypothalamus?
An area of the brain just blow the cerebral hemispheres and under the thalamus it is the centre of the autonomic nervous system.
What is the tympanic membrane?
The eardrum sound waves beat against it, causing vibrations in the small bones of the ear.
What are the semi-circular canals?
Fluid filled canals in the ear that detect movement.
What are the cochlea?
Snail-shaped cavity forming a division within the internal ear.
What are the two types of sensory cells in the eye?
Rods: involved with black and white vision.
Cones: involved with colour vision.
What are the Retina?
Photosensitive layer of the eye; contains several layers of neurone, rods and cones.
What is the cornea?
The Transparent outer layer of the eye.
