uta biol 2457 practical 2

central nervous system

(CNS) brain and spinal cord.

peripheral nervous system

(brain and spinal cord) Connects the central nervous system to the body's organs and limbs.

sensory (afferent) neurons

neurons that carry incoming information from the sensory receptors (sight, smell, sound etc.) to the brain and spinal cord

Interneurons

Central nervous system neurons that internally communicate and intervene between the sensory inputs and motor outputs

motor (efferent) neurons

Nerve cells responsible for making an action or movement happen.Multipolar Shaped Neurons

white matter

myelinated axons

grey matter

unmyelinated neuron cell bodies and short, unmyelinated axons

meninges

three protective membranes that surround the brain and spinal cord. dura mater, arachnoid mater, pia mater

dura matter

thick, outermost layer of the meninges surrounding and protecting the brain and spinal cord

arachnoid mater

weblike middle layer of the three meninges

pia matter

thin, delicate inner membrane of the meninges

cerebrospinal fluid

Fluid in the space between the meninges that acts as a shock absorber that protects the central nervous system.

dendrites

Branchlike parts of a neuron that are specialized to receive information.

cell body (soma)

the part of a neuron that coordinates information-processing tasks and keeps the cell alive

axon hillock

the cone-shaped area on the cell body from which the axon originates

axon

the neuron extension that passes messages through its branches to other neurons or to muscles or glands

Schwann cells

Type of glia in the PNS, Supporting cells of the peripheral nervous system responsible for the formation of myelin.

myelin sheath

covers the axon of some neurons and helps speed neural impulses

Nodes of Ranvier

Gaps in the myelin sheath to which voltage-gated sodium channels are confined.

axon terminals

Branches at the end of the axon that contain tiny pouches, or sacs, called synaptic vesicles.

Cerebrum

Largest part of the brain; responsible for voluntary muscular activity, vision, speech, taste, hearing, thought, and memory.

frontal lobe

A region of the cerebral cortex that has specialized areas for movement, abstract thinking, planning, memory, and judgement

parietal lobe

portion of the cerebral cortex lying at the top of the head and toward the rear; receives sensory input for touch and body position

temporal lobe

A region of the cerebral cortex responsible for hearing and language.

occipital lobe

A region of the cerebral cortex that processes visual information

functional areas

areas of the brain that are specialized in the production of certain tasks

corpus callosum

the large band of neural fibers connecting the two brain hemispheres and carrying messages between them

Diencephalon

thalamus, hypothalamus, epithalamus

thalamus

the brain's sensory switchboard, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla

Hypothalamus

a neural structure lying below the thalamus; directs eating, drinking, body temperature; helps govern the endocrine system via the pituitary gland, and is linked to emotion

pineal gland

produces melatonin

pituitary gland

The endocrine system's most influential gland. Under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands.

pituitary gland anterior

- Growth hormone

--- Drugs for growth hormone deficiency: somatrem (Protropin), somatropin (Humatrope)

--- Drugs for growth hormone excess: bromocriptine (Parlodel), octreotide (Sandostatin)

- Thyroid-stimulating hormone

--- Thyrotropin (Thytropar)

- Adrenocorticotropic hormone

--- Corticotropin (Acthar)

pituitary gland posterior

antidiuretic hormone and oxytocin

brain stem

midbrain, pons, medulla oblongata

midbrain

Region between the hindbrain and the forebrain; it is important for hearing and sight.

pons

sleep and arousal

medulla oblongata

Part of the brainstem that controls vital life-sustaining functions such as heartbeat, breathing, blood pressure, and digestion.

reticular formation

a nerve network in the brainstem that plays an important role in controlling arousal

reticular activating system

Located in the upper brain stem; responsible for maintenance of consciousness, specifically one's level of arousal.

cerebellum

A large structure of the hindbrain that controls fine motor skills.

arbor vitae

white matter of the cerebellum

tree of life

gyri

ridges of the brain

sulci

shallow grooves that separate gyri

central sulcus

Separates frontal lobe from parietal lobe

lateral sulcus

separates the parietal and temporal lobes

parieto-occipital sulcus

separates parietal and occipital lobes

Fissures

deep grooves in the brain

longitude fissure

Crease/line that divides the brain in to left and right side hemisphere.

transverse cerebral fissure

separates cerebrum from cerebellum

ventricles

the two lower chambers of the heart, and they pump blood out to the lungs and body.

Lateral (1st & 2nd) Ventricles

within cerebral hemispheres; separated by septa pellucida

3rd ventricle

found in the diencephalon and communicates with lateral ventricles via intraventricular foramen

4th ventricle

between pons and cerebellum

choroid plexus

A highly vascular portion of the lining of the ventricles that secretes cerebrospinal fluid.

conus medullaris

tapered end of spinal cord

if the conus medullaris is damaged

Conus medullaris syndrome is a type of incomplete spinal cord injury that is less likely to cause paralysis than many other types of spinal cord injuries. Instead, the most common symptoms include: Severe back pain. Strange or jarring sensations in the back, such as buzzing, tingling, or numbness.

cervical spinal nerves

C1-C8

may cause pain that radiates into the shoulder and/or arm, as well as muscle weakness and numbness if damaged

thoracic spinal nerves

T1-T12

back problems

lumbar spinal nerves

L1-L5

injuries generally result in some loss of function in the hips and legs

sacral spinal nerves

S1-S5

If you have sacral nerve damage, you may experience symptoms on one or both sides of the body. Meanwhile, damage to the sacral spine may cause you to lose some function in your legs or hips. You could find it difficult to walk or drive a car

coccygeal spinal nerves

1 pair

Achy or piercing pain in the tailbone

Dorsal, Ventral, & Lateral Horns

Inner part of spinal cord that's made of GRAY matter

dorsal root

the sensory branch of each spinal nerve

dorsal root ganglion

contains cell bodies of sensory neurons

dorsal rootlets

sensory

ventral root

contains axons of motor neurons

If the ventral root of a spinal nerve was severely damaged or cut, it would cut off the pathway of motor information from the spinal cord to the spinal nerve. Therefore, whatever effectors that spinal nerve controlled would no longer work; it would be paralyzed.

ventral rootlets

motor

central canal

transports cerebrospinal fluid (CSF)

if the central canal is damaged

Paralysis or loss of fine control of movements in the arms and hands, with relatively less impairment of leg movements. Loss of or change in sensation below the site of the injury. Loss of bladder control

Olfactory Nerve (I)

sensory, smell

Optic Nerve (II)

vision, sensory nerve

Oculomotor Nerve (III)

- motor

- eye movement narrows pupil and focuses lens

Trochlear Nerve (IV)

- motor

- directs the eyeballs.

Trigeminal Nerve (V)

sensory and motor

- Largest cranial nerves, extending from the pons to the face

- Ophthalmic (V1): nose to eyes to forehead.

- Maxillary (V2): maxillae to temples.

- Mandibular (V3): mandible to frontof ears - Convey sensory impulses fromvarious areas of face (V1 and V2).

- Supply motor fibers (V3) for mastication.

opthalmic

Ophthalmic (V1): nose to eyes to forehead

maxillary

Maxillary (V2): maxillae to temples

mandibular

Mandibular (V3): mandible to front of ears

Abduscens Nerve (VI)

- motor

- extend from just below pons to lateral rectus muscle of eyeballs.

- primarily a motor nerve that directs the eyeballs

Facial Nerve (VII)

sensory and motor; provides motor innervation of facial muscles that are responsible for facial expression, parasympathetic innervation of the glands of the oral cavity and the lacrimal gland, and sensory innervation of the anterior 2/3 the tongue

Vestibulocochlear Nerve (VIII)

sensory

hearing and equilibrium

Glossopharyngeal Nerve (IX)

sensory and motor

taste and swallowing

Vagus Nerve (X)

sensory and motor

Reception of blood pressure and blood gas chemistry, controls smooth movements in digestive system, decreases cardiac muscle contractions, increases secretion of digestive juices

Accessory Nerve (XI)

- motor

- swallowing, head, neck, and shoulder movements

- trapezius and sternocleidomastoid muscles

Hypoglossal Nerve (XII)

motor: muscles of the tongue contribute to swallowing and speech

parasympathetic nervous system

- Rest-and-Digest

- Supports functions that conserve and restore energy during rest and recovery.

- When body is at relaxed.... parasympathetic input dominates over sympathetic.

- 3 decreases... heart rate, bronchial diameter, and pupil diameter

sympathetic nervous system

- "Fight-or-Flight"

- Supports functions that use energy and reduces functions that store energy.

- When body is in vigorous activity.... sympathetic input dominates parasympathetic.

- 3 increases... heart rate/stroke volume, bronchial diameter, and pupil diameter.• Also involved with fear, embarrassment, nervousness, and rage.

- "E situations"... exercise, emergency, excitement, embarrassment

dual innervation

organs that receive instructions from both sympathetic and parasympathetic divisions

dynamic antagonism

between two divisions maintains homeostasis

autonomic ganglia

Collections of nerve cell bodies, belonging to the autonomic division of the peripheral nervous system, that are found in various locations and innervate the major organs.

autonomic reflexes

smooth muscle regulation, heart and blood pressure regulation, regulation of glands, digestive system regulation

pupillary reflex

The automatic process by which the iris contracts and relaxes to control the size of the pupil, in response to the relative brightness of light entering the eye

salivary reflex

food odor detection causes salivation

sweat reflex

Regulates body temperature, in repsonse to stimuli

Gastric Reflex

initiated by presence of food in stomach

micturition reflex

spinal reflex that partly controls urination

defecation reflex

activated by stretch receptors stimulated by filling of the rectum

somatic reflexes

activation of skeletal muscles

gag reflex

A normal reflex mechanism that causes retching; activated by touching the soft palate or the back of the throat.

withdrawal reflex

a spinal reflex that pulls a body part away from a source of pain

stretch reflex

muscle contraction in response to stretching within the muscle

patellar reflex

a reflex extension of the leg resulting from a sharp tap on the patellar tendon; knee jerk