PHYL 141 LAB Exam Practical #3

Autonomic (visceral) reflexes

Mediated through the autonomic nervous system (ANS) (it is involuntary)

Somatic Reflexes

Stimulate skeletal muscles by the somatic division (it is voluntary)

What are the 5 basic components of the reflex arc

Receptor

Sensory neuron

Integration center

Motor Neuron

Effector

What does this picture show?

The 5 components of the Reflex Arc

What are the 2 different types of reflexes?

Simple and Complex

Simple

Monosynaptic (no more than one interneuron), fast acting

Complex

Polysynaptic (more than one interneuron) slower acting

What kind of reflex is the patellar knee jerk reflex considered as?

It is considered a Monosynaptic reflex

Somatic Reflexes (for posture, balance, and locomotion)

Stretch (deep tendon)

Crossed-extensor (withdrawal reflex ex. automatic response to pull away from painful stimuli)

Superficial (reflex resulting from pain and temp change)

Corneal (light reflected off cornea of eye, Nerve V)

Gag (contraction of back of throat, Nerve IX & Nerve X)

Reciprocal Inhibition (reflexive antagonism)

Interneurons help to control or inhibit the action of antagonist muscles to allow agonist muscles to work more efficiently

Autonomic Reflexes (automatic)

Pupillary — light input is the stimulus (contralateral response: opposite stimulation site to response site) & (Ipsilateral response: same stimulation and response site)

Ciliospinal (sensation input)

Salivary (only reflex which glands are the effectors)

What are the 2 main divisions of the Nervous system?

The CNS (central nervous system) and he PNS (Peripheral Nervous system)

What is Nervous tissue made up of?

Neurons (transmits signals) and neuroglia (not capable of generating and transmitting nerve impulses)

Neuroglia (glial cells)

Neuroglia are supporter cells and serves as protectors of the nervous system

What are the 4 types of Neuroglia cells in the CNS

Astrocytes

Microglial cells

Oligodendrocytes

Ependymal Cells

For the PNS, what glial cells would be there?

Schwann cells (forms myelin) and satellite cells

What cell is most abundant in the CNS neuroglia?

Astrocytes

What do Ependymal Cells do?

Ependymal cells line cerebrospinal fluid-filled cavities they also have cilia

Neurons have 2 types of processes

1) Dendrites- receptive regions with neurotransmitter receptors

2) Axons- form impulse generating and conducting region

Myelin sheaths around CNS are generated by

Oligodendrocytes

What are the classifications of Neurons by structure ?

Unipolar, Pseudounipolar, Bipolar, multipolar

Identify this neuron according to structure

Multipolar

Identify this neuron according to structure

Bipolar

Identify this neuron according to structure

Unipolar

Identify this neuron according to structure

Multipolar

Identify this neuron according to structure

unipolar

Afferent (sensory) neurons:

Neurons carrying impulses from sensory receptors in viscera to the CNS (towards the brain)

Efferent (motor) neurons

neurons carrying impulses from the CNS to the viscera and/or body muscles and glands (away from brain)

Central Nervous System (CNS)

brain and spinal CORD

Peripheral Nervous System (PNS)

cranial enerves, spinal nerves, ganglia, and sensory receptors

Sensory

contains nerve fibers that conduct impulses from sensory receptors TOWARDS CNS

Motor

contains nerve fibers that conduct impulses AWAY FROM CNS

Meninges of the brain

3 connective tissue that protects the brain and spinal cord

Can you list the 3 connective tissues that protect the brain and spinal cord

Dura mater (outermost), Arachnoid Mater, and Pia Mater

Cerebrospinal fluid

watery cushion that protects the brain against trauma

Can you name all the cranial nerves from I - XII

I. Olfactory (OH)

II. Optic (OH)

III. Oculomotor (OH)

IV. Trochlear (TO)

V. Trigeminal (TOUCH)

VI. Abducens (AND)

VII. Facial (FEEL)

VIII. Vestibulocochlear (VERY)

IX. Glossopharyngeal (GOOD)

X. Vagus (VELVET)

XI. Accessory (AH)

XII. Hypoglossal (Heaven)

What is Wernicke’s area in the brain known for

speech processing

Vagus Nerve function

Controls involuntary functions of the body (carries somatic moor impulses)

ex. heart rate, digestion, BP

Vestibulocochlear Nerve Function

Balance and hearing, semicircular canals and cochlear branch

What are the 3 major neuron populations in the eye?

photoreceptors, bipolar cells, and ganglion cells

Rods

Specialized photoreceptors for dim light

Cones

color photoreceptors

the Fovea centralis only contains what?

Only contains cones

The Retina periphery contains more what?

Rods

Ganglion cells receive what?

Ganglion cells receieve signals

Normal eye

emmetropic eye

Astigmatism

Irregularities in the curvatures of lens/cornea, presented in younger populations

Presbyopia

Difficulties focusing for near or close vision (blurry vision) due to aging and loss of lens elasticity

Myopic Eye

Nearsighted-ness concave lens

Hyperopic eye

farsighted, convex lens

Name your special senses

vision, hearing, equilibrium, smell and taste

What are some general sensory receptors?

Exteroceptors, Interoceptors, Proprioceptors

Exteroceptors

React to stimuli in the external environment

(ex: cutaneous receptors in skin, receptors in eye)

Interoceptors (visceroceptors)

Responds to stimuli arising in the body

ex. stretch receptors-internal organs, chemoreceptors

Proprioceptors

Respond to internal stimuli from skeletal muscles, joints, and ligaments/ tissues covering bones and muscles (similar to interoceptros)

What are the 4 qualities of cutaneous sensation

tactile, heat, cold, and pain

What receptors are most abundant?

Pain receptors

Adaptation

When a stimulus remains constant without our reaction, the CNS recognizes it and the receptor discharge slows

(ex: clothing on our skin)

WHat are the 3 major areas of the ear

Externa, Middle, Internal Ear

The external and middle ear are responsible for what sense?

hearing

The Internal Ear is responsible for what sense?

sense of balance/ equilibrium

What does the vestibular apparatus contain (equilibrium Apparatus)

contains utricle, saccule, semicircular ducts filled with endolymph

Semicircular canals

Monitor head rotational acceleration (dynamic equilibrium)

The receptors for olfaction (smell) and taste are?

chemoreceptors

What is the organ of smell called?

Olfactory epithelium (found in rook of nasal cavity)

What 3 cell types does the olfactory epithelium have?

1) Olfactory Sensory neurons (bipolar neurons)

2) Supporting cells

3) olfactory stem cells

Taste buds

Receptors for taste that are widely but not uniformly distributed in the oral cavity

Most taste buds are in ?

Papillae (mostly found on dorsal surface of the tongue)

Where can taste buds also be?

soft palate, epiglottis, pharynx, inner cheeks

Each taste bud has two types of modified epithelium?

Gustatory epithelial cells, basal epithelial cells

sensory (afferent) neurons associated with olfaction in the taste buds are?

1) Facial Nerve (VII)

2) Glossopharyngeal (IX)

3) Vagus (X)

Taste can be categorized in 5 basic qualities, which are ?

Bitter, sweet, salty, sour, and umami (savory)