Kin 2500 Exam 6

______________- Paired clusters of gray matter deep in each cerebral hemisphere including the globus pallidus, putamen, and caudate nucleus.

Basal nuclei

Damage to the facial (VII) nerve due to conditions such as viral infection (shingles) or a bacterial infection (Lyme disease) produces ___________ (paralysis of the facial muscles), loss of taste, decreased salivation, and loss of ability to close the eyes, even during sleep. The nerve can also be damaged by trauma, tumors, and stroke

Bell's palsy

Autonomic Nervous System: Autonomic motor neurons convey information from the ________ to smooth muscle, cardiac muscle, and glands and cause the muscles to contract and the glands to secrete

CNS

Medulla Oblongata: Nuclei- ______________- Groups of neurons scattered within the medulla oblongata that regulate heart rate, force of contraction, and blood vessel diameter.

Cardiovascular center

Synapses between Neurons: ___________ synapse- Synapses involving the release of a neurotransmitter from a presynaptic neuron; occur between most neurons and all neurons and effectors.

Chemical

Cerebrospinal Fluid: ________________- A network of capillaries located in the roof of each of the four ventricles of the brain; ependymal cells around these produce cerebrospinal fluid.

Choroid plexus

Components of the limbic system: Limbic lobe- __________- which lies above the corpus callosum

Cingulate gyrus

Sensory and Motor tracts: Direct pathways- _____________- conveys nerve impulses that originate in the cerebral cortex and are destined to cause precise, voluntary movements of skeletal muscles.

Corticobulbar tract

Pons: Nuclei of four pairs of cranial nerves- _______________ nerves- (blank) nuclei in the pons provide motor impulses that control eyeball movement via the (blank) nerves.

Abducens (VI)

Components of the limbic system: ___________- is composed of several groups of neurons located close to the tail of the caudate nucleus.

Amygdala

Organization of Spinal Nerves: _______________roots- The structure composed of axons of motor (efferent) neurons that emerges from the anterior aspect of the spinal cord and extends laterally to join a posterior root, forming a spinal nerve.

Anterior (ventral)

Internal Anatomy of the Spinal Cord: __________________ horns- contain somatic motor nuclei, which are clusters of cell bodies of somatic motor neurons that provide nerve impulses for contraction of skeletal muscles.

Anterior (ventral) gray

Internal Anatomy of the Spinal Cord: _____________- is a wide groove on the anterior (ventral) side.

Anterior median fissure

The Cerebellum: Cerebellar cortex- _____________- deep to the gray matter, white matter tracts of the cerebellum which have a treelike appearance when seen in midsagittal section

Arbor vitae

___________- is a disorder that affects over 18 million people each year in the United States. People who are depressed feel sad and helpless, have a lack of interest in activities that they once enjoyed, and experience suicidal thoughts. There are several types of this.

Depression

Neural Circuits: _______________- A synaptic arrangement in which the synaptic end bulbs of one presynaptic neuron terminate on several postsynaptic neurons.

Divergence

Neural Circuits: ___________ circuit- the nerve impulse from a single presynaptic neuron causes the stimulation of increasing numbers of cells along the circuit. For example, a small number of neurons in the brain that govern a particular body movement stimulate a much larger number of neurons in the spinal cord.

Diverging

Structure of a Single Nerve: __________- a small bundle or cluster, especially of nerve or muscle fibers (cells).

Fasciculi

Structure of the Cerebrum: ___________- deepest groove, fold, or slit that may be normal or abnormal.

Fissures

Medulla Oblongata: Nuclei- ____________- A group of nerve cells in the inferior part of the medulla oblongata (right and left) in which axons of the gracile fasciculus terminate; Nuclei associated with sensations of touch, conscious proprioception, pressure, and vibration are located in the posterior part of the medulla.

Gracile nucleus

Internal Anatomy of the Spinal Cord: _____________- a narrow strip of gray matter connecting the two lateral gray masses within the spinal cord

Gray commissure

Structure of the Cerebrum: ________________- Folds of the cerebral cortex of the brain. Singular is gyrus.

Gyri (convolutions)

Components of the limbic system: Limbic lobe- _______________- is a portion of the parahippocampal gyrus that extends into the floor of the lateral ventricle.

Hippocampus

Basal Nuclei: _________________ is an inherited disorder in which the caudate nucleus and putamen degenerate, with loss of neurons that normally release GABA or acetylcholine. A key sign of this is chorea, in which rapid, jerky movements occur involuntarily and without purpose. Progressive mental deterioration also occurs.

Huntington disease (HD)

____________ of the PNS completely surround axons and cell bodies of neurons.

Neuroglia

___________ is the study of the normal functioning and disorders of the nervous system

Neurology

___________ display great diversity in size and shape ; Cell bodies range in diameter from 5 µm to 135 mm. The pattern of dendritic branching is varied and distinctive for neurons in different parts of the nervous system. A few small (blank) lack an axon, and many others have very short axons

Neurons

Functional Organization of the Cerebral Cortex: Sensory areas- ____________ area- located at the base of the postcentral gyrus superior to the lateral cerebral sulcus in the parietal cortex, receives impulses for taste and is involved in gustatory perception.

Primary gustatory

Functional Organization of the Cerebral Cortex: motor areas- ______________ area- is located in the precentral gyrus of the frontal lobe. Each region in the primary motor area controls voluntary contractions of specific muscles or groups of muscles

Primary motor

Astrocytes: ______________ astrocytes- have many branching processes and are located mainly in gray matter

Protoplasmic

Medulla Oblongata: ____________- A pointed or cone-shaped structure. One of two roughly triangular structures on the anterior aspect of the medulla oblongata composed of the largest motor tracts that run from the cerebral cortex to the spinal cord. A triangular structure in the renal medulla.

Pyramids

______________- can be caused by improperly administered intramuscular injections into the deltoid muscle. The radial nerve may also be injured when a cast is applied too tightly around the mid-humerus. Radial nerve injury is indicated by this, the inability to extend the wrist and fingers

Radial nerve injury (wrist drop)

Branches of the Spinal Nerves: _____________- Branches of a spinal nerve that are components of the autonomic nervous system

Rami communicantes

_________- Fast response to a change (stimulus) in the internal or external environment that attempts to restore homeostasis.

Reflex

Midbrain: Tectum- _______________- 2 superior elevations of the tectum; serve as reflex centers for certain visual activities.

Superior colliculi

Structure of the Cerebrum: The ______________ separates the frontal lobe from the parietal lobe.

central sulcus

The Cerebellum: ____________- A bundle of nerve axons connecting the cerebellum with the brain stem.

cerebellar peduncles

Injury to the hypoglossal (XII) nerve results in difficulty in chewing, _____________ or difficulty in speaking, and dysphagia or difficulty in swallowing. The tongue, when protruded, curls toward the affected side, and the affected side atrophies.

dysarthria

Injury to the glossopharyngeal (IX) nerve causes ______________ or difficulty in swallowing, aptyalia or reduced secretion of saliva, loss of sensation in the throat, and ageusia or loss of taste sensation. The glossopharyngeal nerve may be injured as a result of conditions such as trauma or lesions.

dysphagia

External Anatomy of the Spinal Cord: In adults, it extends from the _____________ to the superior border of the second lumbar vertebra.

medulla oblongata (the most inferior part of the brain)

Protective Structures: _______________- are three protective, connective tissue coverings that encircle the spinal cord and brain. From superficial to deep they are: 1) Dura mater 2) Arachnoid mater 3) Pia mater

meninges

Brain Development: Primary Brain Vesicles- The _____________ or midbrain gives rise to the midbrain and aqueduct of the midbrain (cerebral aqueduct).

mesencephalon

Internal Anatomy of the Spinal Cord: Tracts- ______________ tracts- Tracts consisting of axons that carry nerve impulses away from the brain down the spinal cord

motor (descending)

About 100 substances are either known or suspected ____________. Include acetylcholine (ACh), glutamate, aspartate, gamma aminobutyric acid (GABA), norepinephrine (NE), dopamine (DA), serotonin, endorphins, and nitric oxide (NO)

neurotransmitters

Basal Nuclei: People who have _______________ experience repetitive thoughts (obsessions) that cause repetitive behaviors (compulsions) that they feel obligated to perform.

obsessive-compulsive disorder (OCD)

Synapses between Neurons: the neuron receiving the message is referred to as the ___________ neuron

postsynaptic

Synapses: A _______________ cell is a cell that receives a signal; may be either a nerve cell (carries impulse away from synapse) or effector (responds to impulse at synapse)

postsynaptic

Synapses between Neurons: For synapses between neurons, the neuron sending the signal is called the _______________ neuron

presynaptic

________________- The most basic conduction pathway through the nervous system, connecting a receptor and an effector and consisting of a receptor, a sensory neuron, an integrating center in the central nervous system, a motor neuron, and an effector.

reflex arc

Thalamus: Seven major groups of nuclei- 7. The _______________ surrounds the lateral aspect of the thalamus, next to the internal capsule. This nucleus monitors, filters, and integrates activities of other thalamic nuclei.

reticular nucleus

Neuroglia of the Peripheral Nervous System: ___________________, surround the cell bodies of neurons of PNS ganglia and regulate the exchange of materials between neuronal cell bodies and interstitial fluid

satellite cells

you are probably most aware of ________ reflexes, which involve contraction of skeletal muscles.

somatic

Autonomic Nervous System: Because the _____________ division is the major regulator of the smooth muscle of the cardiovascular system, it has a wider distribution, as blood vessels are located everywhere in the body. The parasympathetic division is the major regulator of the smooth muscle of the digestive and respiratory systems, which are derived from the embryonic gut tube.

sympathetic

Neuralgia (pain) relayed via one or more branches of the trigeminal (V) nerve, caused by conditions such as inflammation or lesions, is called _______________. This is a sharp cutting or tearing pain that lasts for a few seconds to a minute and is caused by anything that presses on the trigeminal nerve or its branches.

trigeminal neuralgia

Injury to the vagus (X) nerve due to conditions such as trauma or lesions causes ____________ or interruptions of sensations from many organs in the thoracic and abdominal cavities, dysphagia or difficulty in swallowing, paralysis of the vocal cords, and tachycardia or increased heart rate.

vagal neuropathy

Injury to the vestibular branch of the vestibulocochlear (VIII) nerve may cause __________ , a subjective feeling that one's own body or the environment is rotating, ataxia (muscular incoordination)

vertigo

The _________ matter is aggregations of myelinated and unmyelinated axons of many neurons; located in the brain and spinal cord. Blood vessels are present

white

Equally important, however, are the ___________ reflexes, which generally are not consciously perceived. These reflexes involve responses of smooth muscle, cardiac muscle, and glands.

autonomic (visceral)

Sensory neurons, called ____________ neurons, convey information to the CNS mainly from visceral organs (smooth muscle organs in the thorax, abdomen, and pelvis)

autonomic (visceral) sensory

______________________- Visceral sensory (afferent) and visceral motor (efferent) neurons. Autonomic motor neurons, both sympathetic and parasympathetic, conduct nerve impulses from the central nervous system to smooth muscle, cardiac muscle, and glands. So named because this part of the nervous system was thought to be self-governing or spontaneous.

autonomic nervous system (ANS)

Synapses between Neurons: _____________, from presynaptic axon to postsynaptic axon.

axoaxonic

Synapses between Neurons: Most synapses between neurons are ____________, from presynaptic axon to postsynaptic dendrite

axodendritic

Nerve Fibers: Part of an axon- Axoplasm is surrounded by a plasma membrane known as the __________

axolemma

Nerve Fibers: Part of an axon- An axon is a long, thin, cylindrical projection that often joins the cell body at a cone-shaped elevation called the ____________

axon hillock

Parts of a Neuron: An axon is a long, thin, cylindrical projection that often joins the cell body at a cone-shaped elevation called the ___________.

axon hillock

Nerve Fibers: Part of an axon- The cytoplasm of an axon, called __________

axoplasm

Synapses between Neurons: others are ___________, from presynaptic axon to postsynaptic cell body (soma)

axosomatic

The _____________ barrier: Allows oxygen and glucose into brain; Protects from harmful substances and pathogens

blood-brain

The _____________ barrier: Proteins and antibiotics cannot cross this; Oxygen, carbon dioxide, anesthetic drugs, and alcohol can cross this

blood-brain

Basal Nuclei: Uncontrollable shaking (tremor) and muscle rigidity (stiffness) are hallmark signs of _______________. In this disorder, dopamine-releasing neurons that extend from the substantia nigra to the putamen and caudate nucleus degenerate.

Parkinson's disease (PD)

Organization of the Nervous System: ______________________- The part of the nervous system that lies outside the central nervous system, consisting of nerves and ganglia.

Peripheral nervous system (PNS)

Basal Nuclei: The third of the basal nuclei is the ________________, which has a large "head" connected to a smaller "tail" by a long comma-shaped "body."

caudate nucleus

Protective Structures: Meninges- __________ mater- This is the innermost meninx, a thin transparent connective tissue layer that adheres to the surface of the spinal cord and brain. It consists of thin squamous to cuboidal cells within interlacing bundles of collagen fibers and some fine elastic fibers. Within the pia mater are many blood vessels that supply oxygen and nutrients to the spinal cord.

Pia

_________- A network of nerves, veins, or lymphatic vessels.

Plexus

The Brainstem and Reticular Formation: ___________- The part of the brain stem that forms a "bridge" between the medulla oblongata and the midbrain, anterior to the cerebellum.

Pons

Structure of Typical Neuron and a Synapse Between Neurons: Arrows indicate the direction of information flow: dendrites → _________ → axon → axon terminals.

cell body

Structural Diversity in Neurons: Whereas the axon branch that extends into the CNS, called the ____________, ends in synaptic end bulbs. The dendrites monitor a sensory stimulus such as touch or stretching. The trigger zone for nerve impulses in a unipolar neuron is at the junction of the dendrites and axon. The impulses then propagate toward the synaptic end bulbs.

central process

The _____________ is the "seat of intelligence." It provides us with the ability to read, write, and speak; to make calculations and compose music; and to remember the past, plan for the future, and imagine things that have never existed before.

cerebrum

The principal plexuses are the _________ plexus, brachial plexus, lumbar plexus, and sacral plexus. A smaller coccygeal plexus is also present; Groups of nerves emerge from the plexuses

cervical

Functions of Cerebrospinal Fluid: _____________ protection- CSF provides an optimal chemical environment for efficient neuronal signaling. Even slight changes in the ionic composition of CSF within the brain can seriously disrupt production of action potentials.

chemical

Hypothalamus: Major functions- Regulation of ______________ and states of consciousness- The suprachiasmatic nucleus establishes patterns of awakening and sleep that occur on a (blank). This nucleus receives input from the eyes (retina) and sends output to other hypothalamic nuclei, the reticular formation, and the pineal gland.

circadian rhythm

Functions of Cerebrospinal Fluid: _____________- CSF is a medium for the minor exchange of nutrients and waste products between the blood and adjacent nervous tissue. The subarachnoid space through which CSF flows is continuous with the perivascular spaces (spaces around the blood vessels that penetrate the brain tissue); together, the CSF and these spaces provide a lymphatic function for the tissue of the brain. See the following section for more on the circulation of CSF.

circulation

Internal Anatomy of the Spinal Cord: The white matter, like the gray matter, is organized into regions. The anterior and posterior gray horns divide the white matter on each side into three broad areas called ____________.

columns

Internal Anatomy of the Spinal Cord: ______________- Each in turn contains distinct bundles of axons having a common origin or destination and carrying similar information. - Anterior (ventral) white - Posterior (dorsal) white - Lateral white

columns

Pons: _____________- The ventral region of the pons forms a large synaptic relay station consisting of scattered gray centers called the (blank). Entering and exiting these nuclei are numerous white matter tracts, each of which provides a connection between the cortex (outer layer) of a cerebral hemisphere and that of the opposite hemisphere of the cerebellum. This complex circuitry plays an essential role in coordinating and maximizing the efficiency of voluntary motor output throughout the body.

Pontine nuclei

Pons: _______________ group- together, the medullary respiratory center and the (blank) help control breathing.

Pontine respiratory

Organization of Spinal Nerves: ______________ roots- The structure composed of sensory axons lying between a spinal nerve and the dorsolateral aspect of the spinal cord.

Posterior (dorsal)

Internal Anatomy of the Spinal Cord: __________________ horns- contain cell bodies and axons of interneurons as well as axons of incoming sensory neurons

Posterior (dorsal) gray

Branches of the Spinal Nerves: ______________- A branch of a spinal nerve containing motor and sensory axons supplying the muscles, skin, and bones of the posterior part of the head, neck, and trunk; serves the deep muscles and skin of the posterior surface of the trunk.

Posterior (dorsal) ramus

Organization of Spinal Nerves: ____________________- A group of cell bodies of sensory neurons and their supporting cells located along the posterior root of a spinal nerve.

Posterior (dorsal) root ganglion

Sensory and Motor tracts: _______________- carry nerve impulses for several types of sensations.

Posterior columns

Internal Anatomy of the Spinal Cord: _____________- is a narrow groove on the posterior (dorsal) side.

Posterior median sulcus

Functional Organization of the Cerebral Cortex: Association areas- _____________________ - is an extensive area in the anterior portion of the frontal lobe that is well-developed in primates, especially humans. The prefrontal cortex is concerned with the makeup of a person's personality, intellect, complex learning abilities, recall of information, initiative, judgment, foresight, reasoning, conscience, intuition, mood, planning for the future, and development of abstract ideas.

Prefrontal cortex (frontal association area)

Hypothalamus: _______________- anterior to the supraoptic region is usually considered part of the hypothalamus because it participates with the hypothalamus in regulating certain autonomic activities. The preoptic region contains the medial and lateral preoptic nuclei

Preoptic region

Synapses: _______________ refers to a nerve cell that carries a nerve impulse toward a synapse

Presynaptic neuron

Functional Organization of the Cerebral Cortex: Sensory areas- ___________ area- located in the superior part of the temporal lobe near the lateral cerebral sulcus, receives information from auditory receptors and is involved in auditory perception.

Primary auditory

Functional Organization of the Cerebral Cortex: Sensory areas- _______________ area- located on the medial aspect of the temporal lobe, receives impulses for smell and is involved in olfactory perception.

Primary olfactory

Functional Organization of the Cerebral Cortex: Sensory areas- _______________ area- located at the posterior tip of the occipital lobe mainly on the medial surface (next to the longitudinal fissure), receives visual information and is involved in visual perception.

Primary visual

Branches of the Spinal Nerves: ___________________- branch of a spinal nerve, follows a specific course to different peripheral regions. The two largest branches, the anterior (ventral) (blank) and posterior (dorsal) (blank), are somatic branches that run in the musculoskeletal wall of the body.

Rami (singular = ramus)

Components of a reflex arc: _______________- The part of the body that responds to the motor nerve impulse, such as a muscle or gland, is the (blank). The patellar reflex is a somatic reflex because its effector is a skeletal muscle, the quadriceps femoris muscle, which contracts and thereby relieves the stretching that initiated the reflex. In sum, the patellar reflex causes extension of the knee by contraction of the quadriceps femoris muscle in response to tapping the patellar ligament.

effector

Components of a reflex arc: ______________- The nerve impulses conduct from the sensory receptor along the axon of a sensory neuron to its axon terminals, which are located in the CNS gray matter. From here, relay neurons send nerve impulses to the area of the brain that allows conscious awareness that the reflex has occurred.

Sensory neuron

Neurons or nerve cells possess ________________, the ability to respond to a stimulus and convert it into a nerve impulse.

electrical excitability

Hypothalamus: Major functions- Regulation of _____________ and behavioral patterns- Together with the limbic system, the hypothalamus participates in expressions of rage, aggression, pain, and pleasure, and the behavioral patterns related to sexual arousal.

emotional

The ________________ of the PNS is called the "brain of the gut" and consists of over 100 million neurons in the GI tract

enteric nervous system (ENS)

The _________________ has both sensory and motor components and can operate independently but they can communicate and are regulated by other branches of the ANS.

enteric nervous system (ENS)

________________- The part of the nervous system that is embedded in the submucosa and muscularis of the gastrointestinal (GI) tract; governs motility and secretions of the GI tract.

enteric nervous system (ENS)

______________ cells are cuboidal to columnar cells arranged in a single layer that possess microvilli and cilia; they line the ventricles of the brain and central canal of the spinal cord. Functionally, they produce, possibly monitor, and assist in the circulation of cerebrospinal fluid. They also form the blood-cerebrospinal fluid barrier

ependymal

Components of a reflex arc: _______________- The distal end of a sensory neuron (dendrite) or an associated sensory structure serves as a sensory receptor. Sensory receptors respond to a specific type of stimulus (a change in the internal or external environment) by generating one or more nerve impulses. In the patellar reflex, sensory receptors known as muscle spindles detect slight stretching of the quadriceps femoris muscle (anterior thigh) when the patellar (knee cap) ligament is tapped with a reflex hammer.

Sensory receptor

The brain and spinal cord are continuous with one another through the ________________ of the occipital bone.

foramen magnum

Functional Organization: Sensory function- _____________ detect internal stimuli, such as an increase in blood pressure, and external stimuli, such as a raindrop landing on your arm. Neurons called sensory (afferent neurons) carry this sensory information into the brain and spinal cord through cranial and spinal nerves.

Sensory receptors

Components of the limbic system: _____________- are located within the septal area formed by the regions under the corpus callosum and the paraterminal gyrus (a cerebral gyrus).

Septal nuclei

Cerebrospinal Fluid: _______________- the lateral ventricles are separated by a thin membrane, the (blank)

Septum pellucidum

Basal Nuclei: Two of the basal nuclei are side-by-side, just lateral to the thalamus. They are the ____________, which is closer to the thalamus

globus pallidus

_____________- an acute, painful inflammation of the nerve ganglia, with a skin eruption often forming a girdle around the middle of the body. It is caused by the same virus as chickenpox.

Shingles

Neural Circuits: ___________ circuit- a presynaptic neuron stimulates a single postsynaptic neuron. The second neuron then stimulates another, and so on. However, most neural circuits are more complex.

Simple series

Functional Organization of the Cerebral Cortex: Association areas- _________________ area- is just posterior to and receives input from the primary somatosensory area, as well as from the thalamus and other parts of the brain. This area permits you to determine the exact shape and texture of an object without looking at it, to determine the orientation of one object with respect to another as they are felt, and to sense the relationship of one body part to another.

Somatosensory association

The Cerebellum: _________________- the transverse fissure is occupied by the (blank), which supports the posterior part of the cerebrum and separates it from the cerebellum; it is a tent like fold of the dura mater that is attached to the temporal and occipital bones

Tentorium cerebelli

___________- A large, oval structure located bilaterally on either side of the third ventricle, consisting of two masses of gray matter organized into nuclei; main relay center for sensory impulses ascending to the cerebral cortex.

Thalamus

Cerebrospinal Fluid: _____________- A slitlike cavity between the right and left halves of the thalamus and between the lateral ventricles of the brain.

Third ventricle

Internal Anatomy of the Spinal Cord: ____________- A bundle of nerve axons in the central nervous system that extend long distances up or down the spinal cord

Tracts

The Cerebellum: ______________- the deep cleft that separates the cerebrum from the cerebellum

Transverse fissure

Pons: Nuclei of four pairs of cranial nerves- _____________nerves- Nuclei in the pons receive sensory impulses for somatic sensations from the head and face and provide motor impulses that govern chewing via the (blank) nerves

Trigeminal (V)

Midbrain: Nuclei of two pairs of cranial nerves- ______________ nerves- Trochlear nuclei in the midbrain provide motor impulses that control movements of the eyeball via the trochlear nerves

Trochlear (IV)

Hypothalamus: _______________- the widest part of the hypothalamus, includes the dorsomedial, ventromedial, and arcuate nuclei, plus the stalk like infundibulum , which connects the pituitary gland to the hypothalamus. The median eminence is a slightly raised region that encircles the infundibulum.

Tuberal region

_______________- which is indicated by an inability to abduct or adduct the fingers, atrophy of the interosseus muscles of the hand, hyperextension of the metacarpophalangeal joints, and flexion of the interphalangeal joints, a condition called this

Ulnar nerve palsy (clawhand)

Medulla Oblongata: Cranial Nerves- _______________ nerves- Nuclei in the medulla receive sensory impulses from and provide motor impulses to the pharynx and larynx and many thoracic and abdominal viscera via the (blank)nerves.

Vagus (X)

The Cerebellum: _______________- The central constricted area of the cerebellum that separates the two cerebellar hemispheres

Vermis

Medulla Oblongata: ___________ matter- The medulla also contains several nuclei, masses of (blank) where neurons form synapses with one another. Several of these nuclei control vital body functions. (example: cardiovascular center)

gray

Protective Structures: ________________- The vertebral foramina of all the vertebrae, stacked one on top of the other, form the vertebral canal. The surrounding vertebrae provide a sturdy shelter for the enclosed spinal cord. The vertebral ligaments provide additional protection.

Vertebral column

Medulla Oblongata: Cranial Nerves- __________________nerves- Several cochlear nuclei in the medulla receive sensory input from and provide motor output to the cochlea of the internal ear via the cochlear branches of the (blank) nerves. These nerves convey impulses related to hearing.

Vestibulocochlear (VIII)

Pons: Nuclei of four pairs of cranial nerves- _______________ nerves- Vestibular nuclei in the pons receive sensory impulses from and provide motor impulses to the vestibular apparatus via the vestibular branches of the (blank) nerves. These nerves convey impulses related to balance and equilibrium.

Vestibulocochlear (VIII)

Functional Organization of the Cerebral Cortex: Association areas- ______________ area- located in the occipital lobe, receives sensory impulses from the primary visual area and the thalamus. It relates present and past visual experiences and is essential for recognizing and evaluating what is seen.

Visual association

Functional Organization of the Cerebral Cortex: Association areas- __________________ area- a broad region in the left temporal and parietal lobes, interprets the meaning of speech by recognizing spoken words. It is active as you translate words into thoughts.

Wernicke's (posterior language)

Medulla Oblongata: ___________ matter- Within the medulla's (blank) are all the sensory (ascending) and motor (descending) tracts extending between the spinal cord and other parts of the brain. Some of the white matter forms bulges on the anterior aspect of the medulla. (example: Pyramids)

White

The ________ matter of the nervous system contains neuronal cell bodies, dendrites, unmyelinated axons, axon terminals, and neuroglia. . It appears grayish, rather than white, because the Nissl bodies impart a gray color and there is little or no myelin in these areas. Blood vessels are present

gray

Protective Coverings of the Brain: Cranial Meninges- __________ mater- The outermost of the three meninges (coverings) of the brain and spinal cord; has two layers.

dura

________________- Areas in the central nervous system and ganglia containing neuronal cell bodies, dendrites, unmyelinated axons, axon terminals, and neuroglia; Nissl bodies impart a gray color and there is little or no myelin in this.

gray matter

Functional Organization of the Cerebral Cortex: Physiological differences also exist; although the two hemispheres share performance of many functions, each hemisphere also specializes in performing certain unique functions. This functional asymmetry is termed ____________________

hemispheric lateralization

Hypothalamus: Major functions- Production of ______________- The hypothalamus produces several (blank) and has two important connections with the pituitary gland, an endocrine gland located inferior to the hypothalamus.

hormones

Internal Anatomy of the Spinal Cord: The gray matter on each side of the spinal cord is subdivided into regions called ________

horns

Functional Organization: Integrative function- The nervous system processes sensory information by analyzing and storing some of it and by making decisions for appropriate responses—an activity known as _____________.

integration

Somatic Nervous System: Somatic sensory neurons convey information to the CNS from sensory receptors- These somatic sensory pathways are involved in the input of information to the CNS for ______________ (processing)

integration

The Diencephalon: Thalamus- ___________________- A large tract of projection fibers lateral to the thalamus that is the major connection between the cerebral cortex and the brain stem and spinal cord; contains axons of sensory neurons carrying auditory, visual, and somatic sensory signals to the cerebral cortex plus axons of motor neurons descending from the cerebral cortex to the thalamus, subthalamus, brain stem, and spinal cord.

internal capsule

Functional Organization: Integrative function- Many of the neurons that participate in integration are ________________, with axons that extend for only a short distance and contact nearby neurons in the brain or spinal cord to set up the complex "circuit boards" of the central nervous system. The vast majority of neurons in the body are these. These neurons make up the majority of the central nervous system.

interneurons

Autonomic Nervous System: Because its motor responses are not normally under conscious control, the action of the ANS is _____________.

involuntary

Fractures in the orbit, brain lesions, damage along the visual pathway, diseases of the nervous system (such as multiple sclerosis), pituitary gland tumors, or cerebral aneurysms (enlargements of blood vessels due to weakening of their walls) may result in visual field defects and loss of visual acuity. Blindness due to a defect in or loss of one or both eyes is called ______________.

anopia

Loss of the sense of smell, called ___________, may result from infections of the nasal mucosa, head injuries in which the cribriform plate of the ethmoid bone is fractured, lesions along the olfactory pathway or in the brain, from meningitis, smoking, or cocaine use.

anosmia

Internal Anatomy of the Spinal Cord: Two grooves penetrate the white matter of the spinal cord and divide it into right and left sides= the ______________ and the posterior median sulcus

anterior median fissure

Thalamus: Seven major groups of nuclei- 1. The ______________ connects to the hypothalamus and limbic system. It functions in emotions, regulation of alertness, and memory.

anterior nucleus

Injury to language areas of the cerebral cortex results in ____________, an inability to use or comprehend words.

aphasia

Protective Coverings of the Brain: Cranial Meninges- __________ mater- The middle of the three meninges (coverings) of the brain and spinal cord.

arachnoid

Nerve Fibers: Part of an axon- The axon and its collaterals end by dividing into many fine processes called axon terminal ________________

arborizations (telodendria)

The processes of ___________ make contact with blood capillaries, neurons, and the pia mater (a thin membrane around the brain and spinal cord)

astrocytes

________________- Provide strength; Maintain the unique permeability characteristics of the endothelial cells; in the embryo, they secrete chemicals that appear to regulate the growth, migration, and interconnections among neurons in the brain

astrocytes

________________- Maintain the appropriate chemical environment for the generation of nerve impulses; Play a role in learning and memory by influencing the formation of neural synapses

atrocytes

Structure of the Cerebrum: The ________________ separates the frontal lobe from the temporal lobe.

lateral cerebral sulcus

Thalamus: Seven major groups of nuclei- 3. Nuclei in the__________ connect to the superior colliculi, limbic system, and cortex in all lobes of the cerebrum. The lateral dorsal nucleus functions in the expression of emotions. The lateral posterior nucleus and pulvinar nucleus help integrate sensory information.

lateral group

The arachnoid mater and pia mater are often referred to collectively as the ____________.

leptomeninges

Hypothalamus: Major functions- Regulation of ____________ and drinking- The hypothalamus regulates food intake through the arcuate and paraventricular nuclei. It also contains a thirst center. When certain cells in the hypothalamus are stimulated by rising osmotic pressure of the extracellular fluid, they cause the sensation of thirst. The intake of water by drinking restores the osmotic pressure to normal, removing the stimulation and relieving the thirst.

eating

______________- A part of the forebrain, sometimes termed the visceral brain, concerned with various aspects of emotion and behavior; includes the limbic lobe, dentate gyrus, amygdala, septal nuclei, mammillary bodies, anterior thalamic nucleus, olfactory bulbs, and bundles of myelinated axons.

limbic system

Parts of a Neuron: Aging neurons also contain ___________, a pigment that occurs as clumps of yellowish brown granules in the cytoplasm. It is a product of neuronal lysosomes that accumulates in a neuron, but does not seem to cause harm to the neuron as it ages

lipofuscin

The Cerebellum: Anterior and posterior _______- govern subconscious aspects of skeletal muscle movements

lobes

External Anatomy of the Spinal Cord: ________________ enlargement- inferior enlargement of the spinal cord that extends from the ninth to the twelfth thoracic vertebra. Nerves to and from the lower limbs arise from this

lumbar

The _______________ differs from other body systems because many of its cells are extremely long. Thus it is difficult to divide the nervous system into discrete organs with their own unique cell populations as we do for the other body systems.

nervous system

The human ___________ can be compared to a supercomputer with nervous tissue being one part of its structure and function; is a highly organized network of two types of cells; it contains billions of neurons and even more neuroglia.

nervous system

The structures that make up the _______________ include the brain, cranial nerves and their branches, the spinal cord, spinal nerves and their branches, ganglia, enteric plexuses, and sensory receptors

nervous system

______________- Body system composed of a network of billions of neurons and neuroglia divided into two main subdivisions, the central (blank) system and the peripheral (blank) system.

nervous system

A ___________ is a functional group of neurons that processes a specific kind of information.

neural circuit

The CNS contains billions of neurons organized into complex networks called _____________, each with its own function

neural circuits

The brain and spinal cord develop from the ectodermal ______________. The anterior part of the (blank) expands, along with the associated neural crest tissue.

neural tube

Histology of Nervous Tissue: ________- Smaller cells that greatly outnumber neurons; Support, nourish, and protect neurons. Continue to divide throughout an individual's lifetime

neuroglia

A ______________ is found only around axons in the PNS.

neurolemma

The outer nucleated cytoplasmic layer of the Schwann cell, which encloses myelinated or unmyelinated axons, is the _______________

neurolemma (sheath of Schwann)

A ___________ is a physician who specializes in the diagnosis and treatment of disorders of the nervous system.

neurologist

The branch of medical science that deals with the normal functioning and disorders of the nervous system is ____________.

neurology

Histology of Nervous Tissue: ________- a nerve cell, consisting of a cell body; Comprise the circuitry connecting all regions of the body to the nervous system. They are highly specialized cells, and lost the ability to undergo mitotic division.

neurons

Certain shellfish and other organisms contain ___________, substances that produce their poisonous effects by acting on the nervous system. One particularly lethal neurotoxin is tetrodotoxin (TTX), present in the viscera of Japanese pufferfish. TTX effectively blocks nerve impulses.

neurotoxins

Synapses: Acetylcholine (ACh) is a __________________- A nerve impulse cannot jump the gap to excite the next cell, so it must rely on these. At a neuromuscular junction synaptic vesicles release the (blank) acetylcholine (ACh). The ACh is picked up by ACh receptors, proteins embedded in the cell membranes of muscle fibers, triggering an action potential which causes the muscle fibers to contract

neurotransmitter

Injury to the vestibular branch of the vestibulocochlear (VIII) nerve may cause ____________ (involuntary rapid movement of the eyeball). Injury to the cochlear branch may cause tinnitus (ringing in the ears) or deafness. The vestibulocochlear nerve may be injured as a result of conditions such as trauma, lesions, or middle ear

nystagmus

Cranial Nerve I: Olfactory (I) nerve- Olfactory nerves join the brain in paired masses of gray matter called the ____________, two extensions of the brain that rest on the cribriform plate.

olfactory bulbs

Autonomic Nervous System: The _________ neurons slow it down - Rest-and-digest

parasympathetic

Autonomic Nervous System: _______________division- One of the two subdivisions of the autonomic nervous system, having cell bodies of preganglionic neurons in nuclei in the brainstem and in the lateral gray horn of the sacral portion of the spinal cord; primarily concerned with activities that conserve and restore body energy.

parasympathetic

Structure of the Cerebrum: The ______________ separates the parietal lobe from the occipital lobe.

parieto-occipital sulcus

Structure of a Single Nerve: ___________-connective tissue wrapping around fascicles in a nerve; a thicker sheath of connective tissue, the (blank), holds many nerve fibers together into bundles called fasciculi

perineurium

Structural Diversity in Neurons: However, the axon branch that extends into the periphery, called the _______________, has dendritic branches at its distal tip

peripheral process

Protective Coverings of the Brain: Cranial Meninges- __________ mater- The innermost of the three meninges (coverings) of the brain and spinal cord.

pia

Despite this ____________, mammalian neurons have very limited powers of regeneration, the capability to replicate or repair themselves

plasticity

The nervous system exhibits _______________ (the capability to change based on experience), but it has very limited powers of regeneration (the capability to replicate or repair damaged neurons).

plasticity

Throughout your life, your nervous system exhibits ___________, the capability to constantly change, grow, and remap itself over the course of your lifetime.

plasticity

Axons from the anterior rami of spinal nerves, except for thoracic nerves T2-T12, form networks on both left and right sides of the body, Each network is called a ____________

plexus

Constrictions in this expanded tube soon appear, creating three regions called _______________: prosencephalon, mesencephalon, and rhombencephalon

primary brain vesicles

Functional Organization of the Cerebral Cortex: Sensory areas- ____________________ area- A region of the cerebral cortex posterior to the central sulcus in the postcentral gyrus of the parietal lobe of the cerebrum that localizes exactly the points of the body where somatic sensations originate.

primary somatosensory

Damage to the oculomotor (III) nerve causes ___________ (drooping) of the upper eyelid, dilation of the pupil, movement of the eyeball downward and outward on the damaged side, loss of accommodation for near vision, and diplopia (double vision).

ptosis

Basal Nuclei: Two of the basal nuclei are side-by-side, just lateral to the thalamus. The __________, which is closer to the cerebral cortex

putamen

Organization of Spinal Nerves: The spinal nerves arise from the spinal cord as a series of small ___________. The two types are anterior (ventral) (blank) and posterior (dorsal) (blank).

rootlets

Basal Nuclei: In _____________, excess dopamine activity in the brain causes a person to experience delusions, distortions of reality, paranoia, and hallucinations.

schizophrenia

Injury to the sciatic nerve results in _____________pain that may extend from the buttock down the posterior and lateral aspect of the leg and the lateral aspect of the foot. The nerve may be injured because of a herniated (slipped) disc, dislocated hip, osteoarthritis of the lumbosacral spine, pathological shortening of the lateral rotator muscles of the thigh, pressure from the uterus during pregnancy, inflammation, irritation, or an improperly administered gluteal intramuscular injection.

sciatica

Brain Development: Both the prosencephalon and rhombencephalon subdivide further, forming ___________________. The prosencephalon, or forebrain, gives rise to the telencephalon and diencephalon, and the rhombencephalon, or hindbrain, develops into the metencephalon and myelencephalon.

secondary brain vesicles

The Somatic Nervous System also consists of motor neurons, called ___________________, that convey information from the CNS to skeletal muscles only. These (blank) pathways are involved in the output of information from the CNS that results in a muscular contraction. Because these motor responses can be consciously controlled, the actions of these parts of the SNS are voluntary.

somatic motor neurons

________________- The portion of the peripheral nervous system consisting of somatic sensory (afferent) neurons and somatic motor (efferent) neurons, that convey information to the CNS from sensory receptors in the skin, skeletal muscles, and joints, and from the receptors for the special senses (vision, hearing, equilibrium, taste, and smell)

somatic nervous system (SNS)

When integration takes place in the spinal cord gray matter, the reflex is a _______ reflex. An example is the familiar patellar reflex (knee jerk).

spinal

Organization of the Nervous System: Central nervous system- _________- A mass of nerve tissue located in the vertebral canal from which 31 pairs of spinal nerves originate; it is enclosed and protected by the bones of the vertebral column in the vertebral canal and contains about 100 million neurons.

spinal cord

The ____________ is located within the vertebral canal of the vertebral column.

spinal cord

The length of the adult ___________ is 42-45 cm (16-18 in.). Its maximum diameter is about 1.5 cm (0.6 in.) in the lower cervical region and smaller in the thoracic region.

spinal cord

______________- Contains neural circuits that control some of your quickest reactions to environmental changes; Is the site for integration of neuronal stimulation

spinal cord

______________- Relays sensory nerve impulses; Is continuous with the brain and together they constitute the central nervous system (CNS)

spinal cord

Each _______________ contains sensory neurons that serve a specific, predictable segment of the body.

spinal nerve

Organization of the Nervous System: Peripheral nervous system- _______________- One of the 31 pairs of nerves that originate on the spinal cord from posterior and anterior roots; they emerge from the spinal cord, each serving a specific region on the right or left side of the body.

spinal nerves

Sensory and Motor tracts: Lateral and anterior _________________ tracts- convey nerve impulses for sensing pain, warmth, coolness, itching, tickling, and deep pressure, and a crude, poorly localized sense of touch.

spinothalamic

Midbrain: Nuclei of two pairs of cranial nerves- These two nuclei also are reflex centers for the __________ reflex, sudden movements of the head and body that occur when you are surprised by a loud noise such as a gunshot- the Superior colliculi and the inferior colliculi

startle

If the accessory (XI) nerve is damaged due to conditions such as trauma, lesions, or stroke, the result is paralysis of the _________________ and trapezius muscles so that the person is unable to raise the shoulders and has difficulty in turning the head.

sternocleidomastoid

Damage to the oculomotor (III) nerve causes ______________ (a condition in which both eyes do not fix on the same object since one or both eyes may turn inward or outward)

strabismus

Cerebrovascular accident (CVA) and Transient ischemic attack (TIA): Destruction of brain tissue (infarction) resulting from obstruction or rupture of blood vessels that supply the brain. Also called a ___________ or brain attack.

stroke

The arachnoid mater and pia mater are often referred to collectively as the leptomeninges. Between these two meninges is a space, the ______________, which contains the shock-absorbing cerebrospinal fluid

subarachnoid space

Protective Structures: Meninges- Between the dura mater and the arachnoid mater is a thin ______________, which contains interstitial fluid.

subdural space

Autonomic Nervous System: The _________ neurons increase heart rate - Fight-or-flight and exercise

sympathetic

Autonomic Nervous System: The motor part of the ANS consists of two branches: the _____________ division and the parasympathetic division

sympathetic

Autonomic Nervous System: _______________division- One of the two subdivisions of the autonomic nervous system, having cell bodies of preganglionic neurons in the lateral gray columns of the thoracic segment and the first two or three lumbar segments of the spinal cord; primarily concerned with processes involving the expenditure of energy.

sympathetic

The site of communication between two neurons is called the ___________

synapse

Medulla Oblongata: Cranial Nerves- _______________ nerves- These fibers are actually part of the vagus (X) nerves. Nuclei in the medulla are the origin for nerve impulses that control swallowing via the vagus nerves (cranial portion of the accessory nerves).

Accessory (XI)

Branches of the Spinal Nerves: _______________- serves the muscles and structures of the upper and lower limbs and the muscles and skin of the lateral and anterior regions of the trunk. Smaller visceral branches, such as the meningeal branch and the communicating rami, form the autonomic pathways to smooth muscle and glandular tissue.

Anterior (ventral) ramus

Internal Anatomy of the Spinal Cord: _____________- anterior to the gray commissure; connects the white matter of the right and left sides of the spinal cord

Anterior (ventral) white commissure

Protective Structures: Meninges- __________ mater- This layer, the middle of the meningeal membranes, is a thin, avascular covering comprised of cells and thin, loose arrays of collagen. It is called this because of its spider's web arrangement of delicate collagen fibers and some elastic fibers. It is deep to the dura mater and is continuous through the foramen magnum with the (blank) of the brain.

Arachnoid

____________ are the largest and most numerous of the neuroglia. They are star-shaped cells that have many armlike processes.

Astrocytes

_________- Damage to the cerebellum can result in a loss of ability to coordinate muscular movements

Ataxia

Functional Organization of the Cerebral Cortex: Association areas- ______________ area- located inferior and posterior to the primary auditory area in the temporal cortex, allows you to recognize a particular sound as speech, music, or noise.

Auditory association

Parts of a Neuron: ____________- The usually single, long process of a nerve cell that propagates a nerve impulse toward the axon terminals. The single axon of a neuron carries nerve impulses toward another neuron, a muscle fiber, or a gland cell.

Axon

Protective Coverings of the Brain: _____________ barrier- A barrier consisting of specialized brain capillaries and astrocytes that prevents the passage of materials from the blood to the cerebrospinal fluid and brain.

Blood-brain

Organization of the Nervous System: Central nervous system- _________- The part of the central nervous system contained within the cranial cavity; it is enclosed and protected by the skull in the cranial cavity and contains about 85 billion neurons.

Brain

Major Parts of the Brain: ____________- The portion of the brain immediately superior to the spinal cord, made up of the medulla oblongata, pons, and midbrain; is continuous with the spinal cord.

Brain stem

Functional Organization of the Cerebral Cortex: ______________- Electrical signals that can be recorded from the skin of the head due to electrical activity of brain neurons.

Brain waves

Functional Organization of the Cerebral Cortex: motor areas- ____________ area- is located in the frontal lobe close to the lateral cerebral sulcus. Motor area of the brain in the frontal lobe that translates thoughts into speech. Also called the motor speech area.

Broca's speech

Parts of a Neuron: ______________- contains a nucleus surrounded by cytoplasm. Its cytoplasm includes typical cellular organelles such as lysosomes, mitochondria, and a Golgi complex

Cell body

Neuroglia, glia, or glial cells constitute about half the volume of the _____________. Neuroglia are smaller than neurons

Central Nervous System

Internal Anatomy of the Spinal Cord: _____________- In the center of the gray commissure is a small space called this; a microscopic tube running the length of the spinal cord and contains cerebrospinal fluid.

Central canal

Organization of the Nervous System: ______________________- That portion of the nervous system that consists of the brain and spinal cord.

Central nervous system (CNS)

Organization of the Nervous System: ______________________- processes many different kinds of incoming sensory information. It is also the source of thoughts, emotions, and memories. Most nerve impulses that stimulate muscles to contract and glands to secrete originate in the (blank).

Central nervous system (CNS)

The Cerebellum: ______________- the superficial layer of the cerebellum; consists of gray matter in a series of slender, parallel ridges called folia.

Cerebellar cortex

The Cerebellum: __________________- lateral "wings: or lobes of the cerebellum

Cerebellar hemispheres

The Cerebellum: Cerebellar cortex- ___________- even deeper, within the white matter, are these regions of gray matter that give rise to axons carrying impulses from the cerebellum to other brain centers and to the spinal cord.

Cerebellar nuclei

Major Parts of the Brain: _______________- posterior to the brainstem; The part of the brain lying posterior to the medulla oblongata and pons; governs balance and coordinates skilled movements.

Cerebellum

Structure of the Cerebrum: ____________- The surface of the cerebral hemispheres, consisting of gray matter; arranged in six layers of neuronal cell bodies in most areas.

Cerebral cortex

Structure of the Cerebrum: ________________- Right and left halves of the cerebrum separated by the longitudinal fissure and connected internally by the corpus callosum.

Cerebral hemispheres

Midbrain: ______________- One of a pair of nerve axon bundles located on the anterior surface of the midbrain, conducting nerve impulses between the pons and the cerebral hemispheres; contain axons of sensory neurons that extend from the medulla to the thalamus

Cerebral peduncles

___________ is a clear, colorless liquid that protects the brain and spinal cord against chemical and physical injuries

Cerebrospinal Fluid

Protective Coverings of the Brain: __________________- A clear fluid produced by ependymal cells that cover choroid plexuses in the ventricles of the brain; the fluid circulates in the ventricles, the central canal, and the subarachnoid space around the brain and spinal cord; protects the brain and spinal cord against chemical and physical injuries.

Cerebrospinal fluid (CSF)

Major Parts of the Brain: ____________- supported on the diencephalon and brainstem; The two hemispheres of the forebrain (derived from the telencephalon), making up the largest part of the brain.

Cerebrum

External Anatomy of the Spinal Cord: ________________ enlargement- superior enlargement of the spinal cord that extends from the fourth cervical vertebra to the first thoracic vertebra. Nerves to and from the upper limbs arise from the (blank).

Cervical

The Diencephalon: ________________- they lie in the wall of the third ventricle, can monitor chemical changes in the blood because they lack a blood-brain barrier. They include part of the hypothalamus, the pineal gland, the pituitary gland, and a few other nearby structures. Functionally, these regions coordinate homeostatic activities of the endocrine and nervous systems, such as the regulation of blood pressure, fluid balance, hunger, and thirst.

Circumventricular organs

Functional Organization of the Cerebral Cortex: Association areas- _______________ area- is bordered by somatosensory, visual, and auditory association areas. It receives nerve impulses from these areas and from the primary gustatory area, primary olfactory area, the thalamus, and parts of the brainstem. This area integrates sensory information from the association areas and impulses from other areas, allowing the formation of thoughts based on a variety of sensory inputs. It then transmits signals to other parts of the brain for the appropriate response to the sensory signals it has interpreted.

Common integrative

External Anatomy of the Spinal Cord: _________________- the tapered portion of the spinal cord inferior to the lumbar enlargement. It ends at the level of the intervertebral disc between the first and second lumbar vertebrae

Conus medullaris

Neural Circuits: _______________- A synaptic arrangement in which the synaptic end bulbs of several presynaptic neurons terminate on one postsynaptic neuron. The medial movement of the two eyeballs so that both are directed toward a near object being viewed in order to produce a single image.

Convergence

Neural Circuits: ___________ circuit- the postsynaptic neuron receives nerve impulses from several different sources. For example, a single motor neuron that synapses with skeletal muscle fibers at neuromuscular junctions receives input from several pathways that originate in different brain regions.

Converging

Structure of the Cerebrum: ________________- The great commissure of the brain between the cerebral hemispheres.

Corpus callosum

Protective Coverings of the Brain: _____________- are continuous with the spinal meninges; have the outer dura mater, the middle arachnoid mater

Cranial meninges

Organization of the Nervous System: Peripheral nervous system- _______________- One of 12 pairs of nerves that emerge from the base of the brain; pass through foramina in the skull; and supply sensory and motor neurons to the head, neck, part of the trunk, and viscera of the thorax and abdomen. Each is designated by a Roman numeral and a name.

Cranial nerves

Protective Coverings of the Brain: _______________- the top portion of the skull, which protects the brain; includes frontal, parietal, occipital, temporal, sphenoid, and ethmoid bones.

Cranium

Medulla Oblongata: Nuclei- ______________- A group of neurons in the inferior part of the medulla oblongata in which axons of the cuneate fasciculus terminate; Nuclei associated with sensations of touch, conscious proprioception, pressure, and vibration are located in the posterior part of the medulla

Cuneate nucleus

Medulla Oblongata: _______________ of pyramids- A crossing-over to the opposite (contralateral) side; an example is the crossing of 90% of the axons in the large motor tracts to opposite sides in the medullary pyramids.

Decussation

Parts of a Neuron: ____________- A neuronal process that carries electrical signals, usually graded potentials, toward the cell body; are the receiving or input portions of a neuron, usually are short, tapering and highly branched.

Dendrites

Components of the limbic system: _____________- lies between the hippocampus and parahippocampal gyrus

Dentate gyrus

______________ are the areas of the skin that provides sensory input to the CNS via one pair of spinal nerves.

Dermatomes

Major Parts of the Brain: ______________- superior to the brainstem; consists of the thalamus, hypothalamus, and epithalamus.

Diencephalon

Protective Structures: Meninges- __________ mater- The most superficial of the three spinal meninges is a thick strong layer composed of dense irregular connective tissue; forms a sac from the level of the foramen magnum in the occipital bone, where it is continuous with the meningeal (blank) mater of the brain, to the second sacral vertebra. It is also continuous with the epineurium, the outer covering of spinal and cranial nerves.

Dura

______________- An organ of the body, either a muscle or a gland, that is innervated by somatic or autonomic motor neurons.

Effector

Synapses between Neurons: ___________ synapse- Synapse in which the plasma membranes of the presynaptic and postsynaptic neurons are tightly bound by gap junctions that contain connexons; ion flow through the gap junctions generates a nerve impulse.

Electrical

Structure of a Single Nerve: ___________- connective tissue wrapping around individual nerve axons (cells); each nerve fiber sits in a loose connective tissue covering, the (blank), which consists of a mesh of collagen fibers, fibroblasts, and macrophages surrounded by endoneurial fluid derived from capillaries.

Endoneurium

Structure of a Single Nerve: ______________- the superficial connective tissue covering around an entire nerve; completing the structure of the nerve is an outer connective tissue sheath, the (blank) which bundles all the fasciculi together to form a single nerve. It is continuous with the dura mater and consists of fibroblasts and thick collagen strands that primarily parallel the long axis of the nerve.

Epineurium

The Diencephalon: ____________- Part of the diencephalon superior and posterior to the thalamus, comprising the pineal gland and associated structures.

Epithalamus

___________________- The presentation of this injury is characterized by an upper limb in which the shoulder is adducted, the arm is medially rotated, the elbow is extended, the forearm is pronated, and the wrist is flexed

Erb-Duchenne palsy (waiter's tip position)

Pons: Nuclei of four pairs of cranial nerves- ________________ nerves- Nuclei in the pons receive sensory impulses for taste and provide motor impulses to regulate secretion of saliva and tears and contraction of muscles of facial expression via the (blank) nerves.

Facial (VII)

Protective Coverings of the Brain: Cranial Meninges: Dura mater- ______________- A small triangular process of the dura mater attached to the occipital bone in the posterior cranial fossa and projecting inward between the two cerebellar hemispheres.

Falx cerebelli

Protective Coverings of the Brain: Cranial Meninges: Dura mater- ____________- a fold of the dura mater extending deep into the longitudinal fissure between the two cerebral hemispheres.

Falx cerebri

Astrocytes: ______________ astrocytes- have many long unbranched processes and are located mainly in white matter

Fibrous

External Anatomy of the Spinal Cord: _______________- non-nervous fibrous tissue of the spinal cord that extends inferiorly from the conus medullaris to the coccyx; an extension of the pia mater that extends inferiorly and fuses with the arachnoid mater and dura mater to anchor the spinal cord to the coccyx.

Filum terminale

The Cerebellum: ________________- on the inferior surface; contributes to equilibrium and balance

Flocculonodular lobe

The Cerebellum: Cerebellar cortex- __________- gray matter arranged in a series of slender, parallel ridges

Folia

Components of the limbic system: __________, stria terminalis, stria medullaris, medial forebrain bundle, and mammillothalamic tract- are linked by bundles of interconnecting myelinated axons.

Fornix

Cerebrospinal Fluid: ____________- A cavity filled with cerebrospinal fluid within the brain lying between the cerebellum and the medulla oblongata and pons.

Fourth ventricle

Functional Organization of the Cerebral Cortex: Association areas- ______________ area- in the frontal cortex is sometimes included in the premotor area. It controls voluntary scanning movements of the eyes—like those you just used in reading this sentence.

Frontal eye field

Functional Organization of the Cerebral Cortex: Association areas- __________________ area- is a motor association area that is immediately anterior to the primary motor area. Neurons in this area communicate with the primary motor cortex, the sensory association areas in the parietal lobe, the basal nuclei, and the thalamus. The premotor area deals with learned motor activities of a complex and sequential nature. It generates nerve impulses that cause specific groups of muscles to contract in a specific sequence, as when you write your name.

Frontal premotor

Parts of a Neuron: __________- Usually, a group of neuronal cell bodies lying outside the central nervous system (CNS).

Ganglion

Neuroglia: _________- Do not generate or propagate nerve impulses. Have the ability to multiply and divide in the mature nervous system

Glia

Medulla Oblongata: Cranial Nerves- ________________ nerves- Nuclei in the medulla relay sensory and motor impulses related to taste, swallowing, and salivation via the (blank) nerves

Glossopharyngeal (IX)

_________________- The abnormal accumulation of CSF may be due to an obstruction to CSF flow or an abnormal rate of CSF production and/or reabsorption. In a baby whose fontanels have not yet closed, the head bulges due to the increased pressure. If the condition persists, the fluid buildup compresses and damages the delicate nervous tissue.

Hydrocephalus

Medulla Oblongata: Cranial Nerves- ____________ nerves- (blank) nuclei in the medulla are the origin for nerve impulses that control tongue movements during speech and swallowing via the (blank) nerves.

Hypoglossal (XII)

The Cerebellum: Cerebellar peduncles- ____________- carry sensory information from the vestibular apparatus of the inner ear and from proprioceptors throughout the body into the cerebellum; their axons extend from the inferior olivary nucleus of the medulla and from the spinocerebellar tracts of the spinal cord into the cerebellum.

Inferior

Midbrain: Tectum- ______________- 2 inferior elevations of the tectum; part of the auditory pathway, relaying impulses from the receptors for hearing in the ear to the thalamus.

Inferior colliculi

Components of a reflex arc: ___________________- One or more regions of gray matter in the CNS act as an integrating center. In the simplest type of reflex, such as the patellar reflex in our example, the integrating center is a single synapse between a sensory neuron and a motor neuron in the spinal cord. A reflex pathway in the CNS that involves one synapse is called a monosynaptic reflex arc.

Integrating center

Functional Organization: _____________- Neurons whose axons extend only for a short distance and contact nearby neurons in the brain, spinal cord, or a ganglion; comprise the vast majority of neurons in the body.

Interneurons

The Diencephalon: Thalamus- ___________________- Bridge of gray matter that joins the right and left halves of the thalamus in about 70 percent of human brains.

Interthalamic adhesion (intermediate mass)

Thalamus: Seven major groups of nuclei- 5. _____________ lie within the internal medullary lamina and make connections with the reticular formation, cerebellum, basal nuclei, and wide areas of the cerebral cortex. They function in pain perception, integration of sensory and motor information, and arousal (activation of the cerebral cortex from the brainstem reticular formation).

Intralaminar nuclei

Internal Anatomy of the Spinal Cord: __________________ horns- Between the anterior and posterior gray horns are these which are present only in the thoracic, upper lumbar, and sacral segments of the spinal cord. The lateral horns contain the cell bodies of autonomic motor nuclei that regulate activity of smooth muscle, cardiac muscle, and glands

Lateral gray

Cerebrospinal Fluid: _______________- A cavity within a cerebral hemisphere that communicates with the lateral ventricle in the other cerebral hemisphere and with the third ventricle by way of the interventricular foramen.

Lateral ventricle

Components of the limbic system: ____________- is a rim of cerebral cortex on the medial surface of each hemisphere.

Limbic lobe

___________ are drugs that block pain and other somatic sensations. (Novocaine), Like TTX, these drugs act by blocking nerve impulses, so pain signals do not reach the CNS.

Local anesthetics

_______________________- results in paralysis of the serratus anterior muscle. The medial border of the scapula protrudes, giving it the appearance of a wing. When the arm is raised, the vertebral border and inferior angle of the scapula pull away from the thoracic wall and protrude outward, causing the medial border of the scapula to protrude

Long thoracic nerve injury (winged scapula)

Components of the limbic system: _________________ of the hypothalamus- are two round masses close to the midline near the cerebral peduncles

Mammillary bodies

Functions of Cerebrospinal Fluid: _____________ protection- The primary function of the CSF is to serve as a shock-absorbing medium. It protects the delicate tissues of the brain and spinal cord from jolts that would otherwise cause them to hit the bony walls of the cranial cavity and vertebral canal. This important fluid also buoys the brain so that it "floats" in the cranial cavity and reduces its weight within the skull.

Mechanical

Medulla Oblongata: Nuclei- ________________- A white matter tract that originates in the gracile and cuneate nuclei of the medulla oblongata and extends to the thalamus on the same side; sensory axons in this tract conduct nerve impulses for the sensations of proprioception, fine touch, vibration, hearing, and equilibrium.

Medial lemniscus

_______________- which is indicated by numbness, tingling, and pain in the palm and fingers. There is also inability to pronate the forearm and flex the proximal interphalangeal joints of all digits and the distal interphalangeal joints of the second and third digits

Median nerve palsy

The Brainstem and Reticular Formation: _____________- Nuclei associated with sensations of touch, conscious proprioception, pressure, and vibration are located in the posterior part of this

Medulla Oblongata

_________________- Nuclei associated with five pairs of cranial nerves

Medulla Oblongata

The Brainstem and Reticular Formation: _____________- the most inferior part of the brain stem; is a continuation of the superior part of the spinal cord. It beings at the foramen magnum and extends to the inferior border of the pons.

Medulla oblongata (or medulla)

Medulla Oblongata: Nuclei- _______________- adjusts the basic rhythm of breathing

Medullary respiratory area

Functional Organization of the Cerebral Cortex: ______________ is the process by which information acquired through learning is stored and retrieved.

Memory

Branches of the Spinal Nerves: __________________- reenters the vertebral canal through the intervertebral foramen and supplies the vertebrae, vertebral ligaments, blood vessels of the spinal cord, and meninges.

Meningeal branch

______________ are connective tissue coverings that surround the spinal cord and brain.

Meninges

_______________ are small cells with slender processes that give off numerous spinelike projections. Unlike other neuroglial cells, which develop from the neural tube, microglial cells originate in red bone marrow and migrate into the CNS as it develops.

Microglia

______________ cells function as phagocytes. Like tissue macrophages, they remove cellular debris formed during normal development of the nervous system and phagocytize microbes and damaged nervous tissue.

Microglial

The Brainstem and Reticular Formation: ____________- The part of the brain between the pons and the diencephalon. Also called the mesencephalon

Midbrain

The Cerebellum: Cerebellar peduncles- ___________- are the largest peduncles; their axons carry impulses for voluntary movements (those that originate in motor areas of the cerebral cortex) to nuclei in the pons. From the nuclei they pass into the cerebellum

Middle

Enteric Nervous System: ___________ neurons of the ENS govern contraction of GI tract smooth muscle to propel food through the GI tract. These neurons also control secretions of the GI tract organs such as acid from the stomach, and endocrine cells, which secrete hormones. Like the two main subdivisions of the ENS is involuntary.

Motor

Functional Organization: ____________ Neurons-Neurons that conduct impulses from the brain toward the spinal cord or out of the brain and spinal cord into cranial or spinal nerves to effectors that may be either muscles or glands. Also called efferent neurons.

Motor

Components of a reflex arc: _______________- Impulses triggered by the integrating center pass out of the spinal cord (or brain stem, in the case of a cranial reflex) along a (blank) to the part of the body that will respond. In the patellar reflex, the axon of the (blank) extends to the quadriceps femoris muscle. While the quadriceps femoris muscle is contracting, the antagonist hamstring muscles are relaxed.

Motor neuron

___________________- Neurons that conduct impulses from the brain toward the spinal cord or out of the brain and spinal cord into cranial or spinal nerves to effectors that may be either muscles or glands.

Motor neuron

Sensory and Motor tracts: Indirect pathways- Rubrospinal tract, Tectospinal tract, Vestibulospinal tract, Lateral and medial reticulospinal tract- These tracts convey nerve impulses from the brain stem and other parts of the brain that govern _____________ movements and help coordinate body movements with visual stimuli. Indirect pathways also maintain skeletal muscle tone, sustain contraction of postural muscles, and play a major role in equilibrium by regulating muscle tone in response to movements of the head.

automatic

Cranial Nerve I: Olfactory (I) nerve- _______________- Bundles of axons that extend from the olfactory bulb posteriorly to olfactory regions of the cerebral cortex.

Olfactory tracts

_______________ - resemble astrocytes, but are smaller and contain fewer processes. Processes are responsible for forming the myelin sheath, a lipid and protein covering around some axons that insulates the axon and increases the speed of nerve impulse conduction

Oligodendrocyte

Two types of neuroglia produce myelin sheaths: __________________

Oligodendrocytes (in the CNS)

Medulla Oblongata: Nuclei- ____________- just lateral to each pyramid is an oval-shaped swelling called this.

Olive

Location of Cranial Nerves I and II: Optic (II) nerve- ____________- A crossing point of the two branches of the optic (II) nerve, anterior to the pituitary gland.

Optic chiasm

Location of Cranial Nerves I and II: Optic (II) nerve- _____________- Bundles of axons that carry nerve impulses from the retina of the eye between the optic chiasm and the thalamus.

Optic tracts

Components of the limbic system: Limbic lobe- ________________- which is in the temporal lobe below

Parahippocampal gyrus

Neural Circuits: _____________ circuit- In this circuit, a single presynaptic cell stimulates a group of neurons, each of which synapses with a common postsynaptic cell. These circuits may be involved in precise activities such as mathematical calculations.

Parallel after-discharge

___________ tissue is a vascular tissue comprised of two types of cells: neurons and neuroglia

nervous

Cranial Nerve I: ___________ nerve- is entirely sensory; it contains axons that conduct nerve impulses for olfaction, the sense of smell

Olfactory (I)

Hypothalamus: Major functions- Control of the ________________- regulates contraction of smooth and cardiac muscle and the secretions of many glands. Axons extend from the hypothalamus to sympathetic and parasympathetic nuclei in the brainstem and spinal cord. Through the (blank), the hypothalamus is a major regulator of visceral activities, including heart rate, movement of food through the gastrointestinal tract, and contraction of the urinary bladder.

ANS

Components of the limbic system: _____________- are flattened bodies of the olfactory pathway that rest on the cribriform plate.

Olfactory bulbs

Organization of the Nervous System: ____________- A cordlike bundle of neuronal axons and/or dendrites and associated connective tissue and blood vessels coursing together outside the central nervous system; each (blank) follows a defined path and serves a specific region of the body.

Nerve

Parts of a Neuron: _______________- General term for any process (axon or dendrite) projecting from the cell body of a neuron.

Nerve fibers

___________ are bundles of axons and their associated neuroglial cells wrapped in layers of connective tissue.

Nerves

______________- the birth of new neurons from undifferentiated stem cells, is normally very limited in adult humans. Repair of damaged axons does not occur in most regions of the CNS.

Neurogenesis

________________- the birth of new neurons from undifferentiated stem cells—occurs regularly in some animals

Neurogenesis

____________- Cells of the nervous system that perform various supportive functions. In the central nervous system include the astrocytes, oligodendrocytes, microglia, and ependymal cells; in the peripheral nervous system include Schwann cells and satellite cells.

Neuroglia (glial cells)

Synapses: __________________- A synapse between the axon terminals of a motor neuron and the sarcolemma of a muscle fiber (cell).

Neuromuscular junction

Parts of a Neuron: Neuronal cell bodies also contain prominent clusters of rough endoplasmic reticulum, termed ____________. The (blank) are responsible for high levels of protein synthesis; proteins play important roles in maintenance and repair, transmission of nerve impulses, and reception of stimuli.

Nissl bodies

Midbrain: Nuclei of two pairs of cranial nerves- ______________ nerves- (blank) nuclei in the midbrain provide motor impulses that control movements of the eyeball, while accessory oculomotor nuclei provide motor control to the smooth muscles that regulate constriction of the pupil and changes in shape of the lens via the (blank) nerves.

Oculomotor (III)

Midbrain: _______________- left and right; look reddish due to their rich blood supply and an iron-coating pigment in the neuronal cell bodies. Axons from the cerebellum and cerebral cortex form synapses in the(blank), which function with the cerebellum to coordinate muscular movements.

Red nuclei

Neural Circuits: _____________ circuit- Some circuits are constructed so that stimulation of the presynaptic cell causes the postsynaptic cell to transmit a series of nerve impulses. One such circuit is called this. In this pattern, the incoming impulse stimulates the first neuron, which stimulates the second, which stimulates the third, and so on. Branches from later neurons synapse with earlier ones. This arrangement sends impulses back through the circuit again and again. Among the body responses thought to be the result of output signals from reverberating circuits are breathing, coordinated muscular activities, waking up, sleeping, and short-term memory.

Reverberating

Neuroglia of the Peripheral Nervous System: ___________________, also called neurolemmocytes, encircle PNS axons, form the myelin sheath around axons, and participate in axon regeneration, which is more easily accomplished in the PNS

Schwann cells

Two types of neuroglia produce myelin sheaths: _________________

Schwann cells (in the PNS)

Enteric Nervous System: ___________ neurons of the ENS monitor chemical changes within the GI tract as well as the stretching of its walls.

Sensory

Internal Anatomy of the Spinal Cord: Tracts- ______________ tracts- consist of axons that conduct nerve impulses from the spinal cord toward the brain

Sensory (ascending)

Organization of Spinal Nerves: ________________- As the sensory posterior root and motor anterior root project laterally from the spinal cord, they converge to form a mixed nerve called this

Spinal nerve trunk

_____________ and the nerves that branch from them are part of the peripheral nervous system (PNS). They connect the CNS to sensory receptors, muscles, and glands in all parts of the body.

Spinal nerves

_____________ are nerves associated with the spinal cord and, like all nerves of the peripheral nervous system (PNS), are parallel bundles of axons and their associated neuroglial cells wrapped in several layers of connective tissue. There are 31 pairs.

Spinal nerves

Midbrain: _______________- left and right part of the midbrain that contains several nuclei which are large, darkly pigmented nuclei. Neurons that release dopamine extend from the this to the basal nuclei and help control subconscious muscle activities.

Substantia nigra

Structure of the Cerebrum: __________- shallower groove or depression between parts, especially between the convolutions of the brain.

Sulci

The Cerebellum: Cerebellar peduncles- _____________- contain axons that extend from the cerebellum to the red nuclei of the midbrain and to several nuclei of the thalamus.

Superior

Hypothalamus: _______________- lies superior to the optic chiasm (point of crossing of optic nerves) and contains the paraventricular nucleus, supraoptic nucleus, anterior hypothalamic nucleus, and suprachiasmatic nucleus. Axons from the paraventricular and (blank) nuclei form the hypothalamohypophyseal tract, which extends through the infundibulum to the posterior lobe of the pituitary.

Supraoptic region

__________- The functional junction between two neurons or between a neuron and an effector, such as a muscle or gland; may be electrical or chemical.

Synapse

Midbrain: ____________- posterior part of the midbrain, contains four rounded elevations

Tectum

Protective Coverings of the Brain: Cranial Meninges: Dura mater- ________________- A transverse shelf of dura mater that forms a partition between the occipital lobe of the cerebral hemispheres and the cerebellum and that covers the cerebellum.

Tentorium cerebelli

Sensory and Motor tracts: Direct pathways- Lateral and anterior ______________ tract- conveys nerve impulses that originate in the cerebral cortex and are destined to cause precise, voluntary movements of skeletal muscles.

corticospinal

By contrast, if integration occurs in the brain stem rather than the spinal cord, the reflex is a ________ reflex. An example is the tracking movements of your eyes as you read this sentence.

cranial

Protective Coverings of the Brain: Note that the ________ dura mater has two layers, compared to the single layer of the spinal dura mater.

cranial

Protective Structures: Meninges- Extending along the entire length of the spinal cord, the ______________ protect the spinal cord against sudden displacement that could result in shock.

denticulate ligaments

Protective Structures: Meninges- Triangular-shaped membranous extensions of the pia mater suspend the spinal cord in the middle of its dural sheath. These extensions, called _____________ are thickenings of the pia mater. They project laterally and fuse with the arachnoid mater and inner surface of the dura mater between the anterior and posterior nerve roots of spinal nerves on either side

denticulate ligaments

Knowing which spinal cord segments supply each ________________ makes it possible to locate damaged regions of the spinal cord. The nerve supply in adjacent (blanks) overlaps somewhat.

dermatome

Brain Development: Primary Brain Vesicles- The ______________ forms the thalamus, hypothalamus, epithalamus, and the third ventricle.

diencephalon

Hypothalamus: adjacent to the midbrain, is the most posterior part of the hypothalamus. It includes the (blank) and posterior hypothalamic nuclei. The ______________ are two small, rounded projections that serve as relay stations for reflexes related to the sense of smell

mammillary bodies

Thalamus: Seven major groups of nuclei- 2. The ___________ connect to the cerebral cortex, limbic system, and basal nuclei. They function in emotions, learning, memory, awareness, and cognition (thinking and knowing).

medial nuclei

Brain Development: Primary Brain Vesicles- The ________________ becomes the pons, cerebellum, and upper part of the fourth ventricle.

metencephalon

Thalamus: Seven major groups of nuclei- 6. The _______________ forms a thin band adjacent to the third ventricle and has a presumed function in memory and olfaction.

midline nucleus

Functional Organization: Motor function- Once sensory information is integrated, the nervous system may elicit an appropriate motor response, such as muscular contraction or glandular secretion. The neurons that serve this function are called ____________________. They carry information from the brain toward the spinal cord or out of the brain and spinal cord to effectors (muscles and glands) through cranial and spinal nerves. Stimulation of the effectors by (blank) causes muscles to contract and glands to secrete.

motor neurons (efferent neurons)

Brain Development: Primary Brain Vesicles- The _______________ forms the medulla oblongata and lower part of the fourth ventricle

myelencephalon

____________- Multilayered lipid and protein covering, formed by Schwann cells and oligodendrocytes, around axons of many peripheral and central nervous system neurons.

myelin sheath

Axons that are surrounded by a multilayered lipid and protein covering, called the myelin sheath, are _____________. The sheath electrically insulates the axon of a neuron and increases the speed of nerve impulse conduction.

myelinated (Axons without such a covering are unmyelinated)

A _________ impulse travels rapidly and at a constant strength; travel these great distances at speeds ranging from 0.5 to130 meters per second (1 to 280 mi/hr)

nerve impulse

Histology of Nervous Tissue: ____________________- A wave of depolarization and repolarization that self-propagates along the plasma membrane of a neuron; also called a nerve action potential; it is an electrical signal that propagates along the surface of the membrane of a neuron.

nerve impulse (action potential)

Histology of Nervous Tissue: ____________________- It begins and travels due to the movement of ions (such as sodium and potassium) between interstitial fluid and the inside of a neuron through specific ion channels in the neuron's plasma membrane. Once begun, a (blank) travels rapidly and at a constant strength.

nerve impulse (action potential)

Brain Development: Primary Brain Vesicles- The ______________ develops into the cerebrum and lateral ventricles

telencephalon

Hypothalamus: Major functions- Control of body ______________- If the (blank) of blood flowing through the hypothalamus is above normal, the hypothalamus directs the autonomic nervous system to stimulate activities that promote heat loss. When blood (blank) is below normal, the hypothalamus generates impulses that promote heat production and retention.

temperature

Components of the limbic system: Two nuclei of the __________, the anterior nucleus and the medial nucleus, participate in limbic circuits.

thalamus

Thalamus: Seven major groups of nuclei- 4. Five nuclei are part of the _____________. The ventral anterior nucleus contributes to motor functions, and possibly movement planning. The ventral lateral nucleus connects to the cerebellum and motor parts of the cerebral cortex. Its neurons are active during movements on the opposite side of the body. The ventral posterior nucleus relays impulses for somatic sensations such as touch, pressure, proprioception, vibration, heat, cold, and pain from the face and body to the cerebral cortex. The lateral geniculate nucleus relays visual impulses for sight from the retina to the primary visual area of the cerebral cortex. The medial geniculate nucleus relays auditory impulses for hearing from the ear to the primary auditory area of the cerebral cortex.

ventral group