unit 5 : organization of the nervous sytem

Question 1

what does the brain do?

Answer 1

sensation/perception, movement, maintain the internal environment, tells time, preservation of the species, adaptation

Question 2

divisions of the nervous sytem

Answer 2

central and peripheral nervous systems

Question 3

central nervous system

Answer 3

brain + spinal cord

Question 4

peripheral nervous system

Answer 4

autonomic nervous system (sympathetic and parasympathetic nervous system) + somatic nervous system

Question 5

enteric nervous system

Answer 5

one of the main divisions of the autonomic nervous system and consists of a mesh-like system of nerves that governs that function of the GI tract
- it can act independently of the sympathetic and parasympathetic nervous systems, although it may be influenced by them

Question 6

the nervous system develops from

Answer 6

the neural crest cells of the ectoderm, the surface layer of embryonic tissue

Question 7

neural crest cells will differentiate into separate groups of neurons

Answer 7

these groups include sensory neurons of cranial nerve ganglia, dorsal root ganglia, autonomic ganglion cells of the sympathetic and parasympathetic nervous system. in addition, these cells become endocrine cells

Question 8

brain ventricular system

Answer 8

a series of connecting hollow spaces called ventricles that are filled with cerebrospinal fluid.
- consists of two lateral ventricles, the third ventricle, and the fourth ventricle

Question 9

forebrain

Answer 9

telencephalon
- cerebral hemispheres
- amygdala
- hippocampus
- basal ganglia
- septum
diencephalon
- thalamus
- hypothalamus

Question 10

hindbrain

Answer 10

cerebellum, pons, medulla

Question 11

brain stem

Answer 11

diencephalon
- thalamus
- hypothalamus
midbrain
hindbrain
- cerebellum
- pons
- medulla

Question 12

dermatome

Answer 12

an area of skin that is mainly supplied by a single spinal nerve, each nerve relays sensation from a particular region of skin to the brain

Question 13

vertebrae

Answer 13

cervical, thoracic, lumbar, sacral, and coccygeal segments

Question 14

gray matter

Answer 14

made up largely of cell bodies, whereas the white matter is made up of fiber tracts that ascend and descend to and from the brain.

Question 15

the gray matter contains

Answer 15

the cells of the spinal cord

Question 16

the white matter contains the

Answer 16

axon/fiber pathways

Question 17

medulla oblongata

Answer 17

responsible for autonomic functions ranging from vomiting to sneezing.
- contains the cardiac, respiratory, vomiting, and vasomotor centers and theregore deals with the autonomic functions of breathing, heart rate, and blood pressure

Question 18

pons

Answer 18

notable for containing nuclei of the reticular formation, which plays a crucial role in maintaining behavioral arousal and consciousness, and also is important for having several areas that control the changes in physiological variables that occur when we move from arousal to sleep and sleep to arousal
- major crossing of fibers from one side of the brain to the other

Question 19

cerebellum

Answer 19

important for the control of complex, coordinated behaviors
- has two hemispheres and a structure called the vermis
- the middle parts, including the vermis are important for smoothing out of movements.
- the lateral parts are important for coordinating skilled movements that involve sequences of behavior in real time - like learning to make a bank shot in basketball
- also involved in teh acquisition of motor skills

Question 20

the acquisition of complex motor skills requires

Answer 20

numerous reciprocal connections between the cerebellum and motor contex

Question 21

tegmentum

Answer 21

ventral and below the cerebral aqueduct

Question 22

periaqueductal gray

Answer 22

lies adjacent to the cerebral aqueduct and is important for pain perception. it is a source of neurons that make opiate-like neurotransmitters called endorphins and contains receptors that bind endorphins and other opiate like substances.

Question 23

sources of efferent cranial nerves and terminal nuclei of afferent cranial nerves

Answer 23

Cranial nerves are the nerves that emerge directly from the brain, in contrast to spinal nerves. 10 of the cranial nerves originate in the brainstem. Cranial nerves relay information between the brain and parts of the body, primarily to and from regions of the head and neck. The motor nuclei are located ventrally (as in the spinal cord) while the sensory nuclei are located dorsally (also as in the spinal cord)

Question 24

thalamus

Answer 24

top of the brainstem and is one of the largest collections of nuclei in the brain
- processes the information and then passess it on to the appropriate primary sensory cortex for further processing

Question 25

hypothalamus

Answer 25

another large collection of nuclei
- has areas concerned with the control of: hunger, thirst, heart rate, sexual behavior, body temp, arousal, aggression, and respiration
- it also controls the ANS and the endocrine system via control of the pituitary

Question 26

frontal lobe

Answer 26

sits in front of the central fissure or central sulcus. the more anterior parts are called orbitofrontal cortex and are concerned with the planning, execution, and control of movements

Question 27

parietal lobe

Answer 27

located behind the central fissure and contains the postcentral gyrus, which is responsible for your ability to feel things touching the surface of your body

Question 28

topographic organization

Answer 28

adjacent body locations are represented by adjacent regions on the cortex. this is seen in both primary motor cortex

Question 29

somatosensory mouseunculus

Answer 29

Most likely, every mammalian species has cortex organized this way. This is an example of the mouseunculus and location of whisker barrels in the mouse cortex. Mice receive enormous amounts of information through their snout whiskers, so the cortex devoted to the whiskers is sizeable, and distorts the mouse sensory mouseunculus.

Question 30

layers of cerebral cortex

Answer 30

The layers of the cerebral cortex, (a) and (b), and a cortical pyramidal cell (c). Part (a) is stained (Nissl stain) to show cell bodies. Part (b) shows shapes and positions of typical cells, using the Golgi stain. Parts (a) and (b) are enlarged about 60 times. Part (c) shows a pyramidal cell enlarged about 200 times. All of the cell is seen, except that the axon continues off the bottom of the figure.

Question 31

basal ganglia

Answer 31

The basal ganglia: amygdala, striatum (caudate plus putamen), and globus pallidus. Notice that, in this view, the right globus pallidus is largely hidden behind the right thalamus, and the left globus pallidus is totally hidden behind the left putamen.

Question 32

reticular activating system

Answer 32

a region in the middle of the brain characterized by a mixture of cells and fiber pathways. stimulation of the RAS produce a waking EEG, whereas damage to it produces a slow-wave sleeplike EEG

Question 33

limbic system structures

Answer 33

amygdala, hippocampus, cingulate cortex, fornix, septum, and mammillary body

Question 34

meninges

Answer 34

three membranes that envelop the brain and spinal cord
- dura mater
- arachnoid mater
- pia mater
cerebrospinal fluid is located in the subarachnoid space between the arachnoid matter and the pia mater. the primary function of the meninges is to protect the central nervous system

Question 35

brain ventricular system

Answer 35

a series of connecting hollow spaces called ventricles that are filled with cerebrospinal fluid.
- consists of two lateral ventricles, the third ventricles, and the fourth ventricle
- continous with the central canal of the spinal cord

Question 36

circumventricular organs

Answer 36

structures in the brain characterized by their extensive and highly permeable microvasculature, unlike those in the rest of the brain where there exists a blood brain barrier (BBB). The term “circumventricular organs” was originally proposed in 1958 by Austrian anatomist Helmut Hofer, in recognition of the distribution of the structures around the ventricular system of the brain. The circumventricular organs are midline structures around the third and fourth ventricles that are in contact with blood and cerebrospinal fluid, and allow for the linkage between the CNS and peripheral circulation.