the nervous system Flashcards
what are molecular messages
circulate in the blood. They have local effects that vary in speed (generally slow).
- Many aspects of control require speed. The nervous systems speeds up the rate at which messages are
communicated. It records decisions over time to build a library of how to respond to different situations.
what are the 2 parts the nervous system is made up of
1- perirpheral nervous system:
2- central nervous system:
Peripheral nervous system:
attached to the spinal cord or cranial nerves attached to the
brain. They can receive or send information to and from the periphery.
central nervous system
has the brain and spinal cord. The CNS receives inputs. It analyses, interprets
and stores it in the memory. It then initiates and controls the output (action or response).
what are a bundle of axons called
nerves
what are a bundle of cell bodies called
ganglia
Forebrain (Cerebrum) contain?
Includes the cerebral hemispheres and diencephalon (thalamus and hypothalamus).
what does the midbrain do?
Vision, hearing, motor control, sleep/wake, arousal (alertness), and temperature regulation
what does the hindbrain do?
Includes the pons, medulla and cerebellum
what does the thalamus do?
Process sensory information and relays to the cerebrum.
- Also involve in memory and emotional functions of the limbic system.
what does the hypothalamus do?
Control of endocrine (regulates homeostasis) and autonomic nervous systems.
what does the cerebellum do?
Functions in regulating muscle tone, co-ordination of movement, posture and balance.
what does the cerebral cortex do?
Functions in neural integration.
frontal, parietal, temporal, occipital
what does the brain stem include?
Includes the midbrain, pons and medulla.
- Site of cardiac, vasomotor and respiratory centres.
what does the spinal cord do?
Functions in conduction with bundles of neves conducting information up and down the cord.
- Neural integration, locomotion and reflexes.
what are the 3 parts to a neuron?
1- cell body
2- dendrites
3- axon
what is mylein made out of
gial cells covers the axon to insulate the neurons electrical activity from surrounding neurons. in the PNS schwann cells make mylein
what does the CNS and PNS develop from
ectoderm - CNS
neural crest cells - PNS
what are the two different spinal roots
1- The dorsal root consists of bipolar ganglion cells where the sensory neurons receive information.
2- The ventral root consists of ventral horn cells where the motor neurons send information.
what are nerves covered in for protection?
1- cerebrospinal fluid
2- menginges
Cerebrospinal fluid
It protects the brain, provides nutrients and removes wastes and debris that is reabsorbed into the blood system via ventricles.
meninges
fibrous connective tissue membranes that envelope the brain and spinal cord. Lay between the nervous tissue and the bone and protect the CNS, provide it with nutrients and remove the waste products.
Cranial nerves
- olfactory sensory nerve for smell.
- optic sensory nerve for vision.
- trigeminal sensory nerve for touch and temp
- vagus (mixed nerve)
- vestibulocochlear sensory nerve for hearing
Spina bifida
failure of the vertebral column to unite at the midline.
