Nervous System Unit Lesson 3: Central Nervous System Flashcards
what is the CNS composed of
the brain and the spinal cord
what is the PNS composed of
the nerves that exist outside of the CNS
where is sensory information received(which leads to the initiation of motor control)
in the central nervous system
what are the brain and spinal cord protected by
meninges and bone
what are meninges
protective membrane that wraps both components of the CNS
what is the function of cerebrospinal fluid and where is it located
located in spaces between the meninges and nervous structures, it acts as a protective cushioning for the CNS
what are ventricles and where are they located
located in the brain, ventricles are hollow, interconnecting cavities
what is the function of ventricles
they produce and act as a reservoir for cerebrospinal fluid(extra fluid is drained into the cardiovascular system)
what is the spinal cord
the collection of nervous tissue that runs between the vertebra that compose the spine
where is the central canal in the spine and what is it responsible for
the central canal is located at the center of the spinal cord and it is responsible for holding cerebrospinal fluid
what is the main purpose of the spinal cord
it is to provide a means of communication between the brain and the peripheral nerves. it acts as an intermediary that passes information between the brain and the effector/sensory nerves
how can the human brain be broken down into parts
it can be broken down into the cerebrum, diencephalon, cerebellum and the brainstem
what is the cerebrum and what is its function
the cerebrum is the largest portion of the brain. its most important ability is to perform conscious thought
how can the cerebrum be divided
it can be divided into cerebral hemispheres
what is the corpus callosum
a deep longitudinal fissure that separates the two cerebral hemispheres which allows for communication between the two
what is the cerebral cortex
the wrinkled outer region of the cerebrum
what are the creases in the nervous tissue called
sulci
what are the bumps in the nervous tissue called
gyri
what is the advantage of the folds in the nervous tissue
increases surface area to greater pack in neurons
how can the 2 major sulci along the cerebrum be divided into
4 lobes– frontal lobe, parietal lobe, occipital lobe, and temporal lobe
what is the cortex responsible for
primary motor and sensory areas, association areas, and processing centres
what are association areas and what is it responsible for
areas of the cortex where memories are stored and used in recognition
what are processing centres and what is it responsible for
areas of the cortex where higher-level analytical functions are carried out such as reasoning and planning
what is white matter in the brain responsible for
movement of signals across and around the brain
what are basal nuclei
masses of grey matter responsible for integrating/regulating motor commands
what is the diencephalon
the region containing the hypothalamus and the thalamus
what is the hypothalamus and what is its function
an integrating centre that helps maintain homeostasis. it serves as a link between the endocrine and nervous system as it controls the pituitary gland
what is the function of the thalamus
to receive all sensory input except for smell
how does information arrive to the thalamus
information arrives via cranial nerves and tracts from the spinal cord
what does the thalamus do with the received information
the thalamus takes the information and sends it to the relevant part of the brain (if sent at all)
what is the pineal gland and what is it responsible for
the last part of the diencephalon which is responsible for the secretion of the hormone melatonin
what is the cerebellum
the cauliflower-shaped region of brain that lies underneath the occipital love at the posterior end of the skull
what is the function of the cerebellum
it functions to coordinate the body– it receives sensory input from joints and muscles as well as motor output from the cortex about where portions of the body should be located
describe the structure of the brainstem
it is composed of the midbrain, the pons, and the medulla oblongata
what is the function of the midbrain
works as a relay station between the cerebrum and spinal cord or cerebellum
describe the pons and its function
contains axons that travel between the cerebellum and the rest of the CNS, works with medulla oblongata to control breathing
what is the function of the medulla oblongata
it is responsible for regulating autonomous vital functions like heartbeat, breathing, blood pressure, etc
what important system does the brain stem contain
the reticular activating system (RAS) that is responsive to external stimuli
describe the RAS
it is a collection of nuclei and fibres that extend the length of the brain stem
what happens when a stimulus is received by the RAS
it might cause it to send a signal to the thalamus which may or may not relay the signal to the cerebrum
