Intro to nervous Quiz 2 Flashcards
what is the central nervous system?
brain and spinal cord
functions in the integration of information - the brain is also the site of centers for intellect, emotions, behaviour and memory
what is the parasympathetic nervous system?
the peripheral nervous system connects the central nervous system to sensory receptors, muscles and glands
PNS is subdivided into:
somatic nervous system (SNS)
autonomic nervous system (ANS)
further subdivided into sympathetic division and parasympathetic division
c. enteric nervous system (ENS) – the brain of the gut
what are the two subdivisions of the efferent neurons of the peripherlal nervous system?
i) somatic motor division - controls skeletal muscles
ii) autonomic division - controls contraction and secretion in the various internal organs.
what are the 3 divisions of afferent neurons in the peripheral nervous system?
i) somatic sensory division
ii) autonomic sensory division
iii) enteric sensory division
what does white matter consist of?
concentration of myelinated axons; the myelin imparts a white color
what does grey matter consist of?
clusters of nerve cell bodies, dendrites, axon terminals, unmyelinated axons, and/or neuroglia; greyish color due to lack of myelin and presence of Nissl Bodies (ribosomes)
what is the orientation of grey matter and white matter in the spinal cord?
inner grey matter shaped like a butterfly & outer white matter
what is the orientation of grey matter and white matter in the brain?
opposite orientation; thin outer layer of grey matter & inner white region with nuclei of grey matter found in concentrations
what are nuclei?
masses of cell bodies and dendrites deep within the brain
what is the brain?
-registers sensations, analyses them, makes a decision, and initiates an action.
-also sites of the centres for intellect, emotions, behavior and memory
what is the cerebrum?
largest portion of the brain
what is the cerebral cortex?
outer gray matter (cell bodies, dendrites, unmyelinated axons, neuroglia)
well developed in humans where it expands and wraps around the midbrain
divided into left and right hemispheres
highly folded to accommodate an increased number of interneurons
what are the 4 lobes of the cerebrum?
frontal lobes: personality, intelligence, judgment, language Posterior part of the frontal lobe contains the motor cortex
parietal lobes: language and somatosensory
temporal lobes: hearing, language, and smell
occipital lobes: interpretation of visual stimuli
what are the functional areas of the cerebral cortex?
sensory areas - interpret sensory input
motor areas- determine the motor output
association areas- emotions, reason
what is the inner white matter?
-groups of myelinated axons called tracts
-convey information from one part of the brain to another
-include corpus callosum- “which communicates between the right and left hemispheres
what are the basal ganglia?
-involved in the control of large, automatic muscle movements and muscle tone
-cells of basal ganglia lose function with Parkinson’s
leads to shaking loss of facial expression and arm swing
what is the limbic system?
-emotional brain - pain, pleasure anger
-includes the amygdala. important in emotional response to stimuli like fear.
-note: hippocampus campus is important for the creation of new memories. these memories may be destroyed by alzeihmers
what is in the diencephalon?
thalamus and hypothalamus (pituitary gland)
what is the thalamus?
-major relay station for sensory impulses to sensory areas of the cerebral cortex from the spinal cord and brainstem
-contribute to motor function from the cerebellum and basal ganglia to motor areas of the cerebral cortex
-also relays impulses between different areas of the cerebrum
what is the function of the Pituitary Gland and Hypothalamus?
Both are involved in hormone secretion and storage
-pituitary gland releases hormones and is subdivided into the anterior pituitary and posterior pituitary each releasing different hormones
-hypothalamus is the communication center between the endocrine system and the nervous system; regulates the release of hormones from the pituitary gland
-Both work together to regulate hunger, thirst, sexual response, pleasure, body temperature (thermostat), and the relaxation state of the body versus the flight-or-fight response
what is the cerebellum?
-involved in unconscious regulation of balance and some locomotory movements such as hand-eye coordination
-involved posture and balance
what is the brainstem?
-midbrain, pons, and medulla oblongata
-three regions are involved in relaying nerves to and from the spinal cord to the brain
-Location of the nuclei of cranial nerves
what is the medulla oblangata?
-thickened stalk at the base of the brain which controls subconscious activities such as respiration, blood pressure, heart rate
-Damage to this area of the brain during a stoke leads to death
-Location of the reticular activating center that wakes up your cerebrum each morning
what are the functions of the spinal cord?
- integrates simple responses to certain stimuli (reflexes)
- relays information to and from the brain
what is the spinal cord composed of?
-Composed of outer white matter and inner gray matter (opposite to the brain);
-white matter contains myelinated axon tracts that ascend with sensory information or descend with motor information
-Gray matter possess many interneurons which synapse with sensory and motor neurons as well as other interneurons
what are reflexes?
fast, automatic, pre-programmed responses to internal or external stimuli
They control some skeletal muscle actions, breathing rate, heart rate, and secretions from sweat glands
May be learned or inborn
what are spinal reflexes?
the most basic form of response to stimuli and does not require brain input
what are the basic components of a reflex arc?
Requires: sensory organ or affector sensory neuron interneuron motor neuron effector such as muscle or gland