Anatomy and Physiology II

What kind of information of the dorsal nerve roots of the spinal cord carry? The ventral nerve roots?

Dorsal: sensory/afferent fibers Ventral: motor/efferent fibers

some of the more important neurotransmitters include the following:

acetylcholine, norepinephrine, gamma-aminobutyric acid (GABA), dopamine, enkephalins, serotonin

nociceptors are not found in which organ

brain

The central nervous system consists of

brain and spinal cord and their associated structures

norepinephrine, dopamine, and epinephrine belong to a group of neurotransmitters known as

catecholamines

the reflective tapetum lucidum is formed on the

choroid

which stucture contains the muscles that adjust the shape of the lens of the eye

ciliary body

the somatic nervous system carries out

conscious activities, such as walking, eating and so on

The nervous system is the body's

control center

which causes the greatest degree of light refraction in the eye

cornea

the _____connects the two halves of the brain

corpus callosum

What is the parasympathetic nervous system known as?

cranial-sacral system

What is the resting membrane potential?

difference in electrical charge across neuronal membrane

the function of mucus in the nasal cavities is to

dissolve odor molecules for detection by the receptor cells

the autonomic nervous system perfroms functions that

don't require conscious thought, such as breathing, blood pressure, and heart rate

What kind of information do the dorsal horns and ventral horns of the spinal cord carry?

dorsal horns: forward sensory(afferent) nerve impulses to brain or other parts of spinal cord ventral horns: forward motor(efferent) nerve impulses to the spinal nerves

what is the test for a proprioception deficit

flip over a foot while the animal is standing and see if the animal corrects the position

Why are the general senses referred to as general?

general senses are distributed generally throughout the body

What is the difference between grey matter and white matter besides color?

grey matter is found in the outer layer of the brain, the cerebral cortex; where the most neuron cell bodies and where most of the nerve impulse are start, white matter are the fibers beneath the cortex and corpus callosum (fibers that connect the two halves of the cerebral cortex)

What kinds of stimuli can neurons detect?

hot, cold, touch, pressure, stretch or other physical changes from the inside or outside the body

central temperature receptors that monitor the body's internal termperature are located within which structure of the brain

hypothalamus

reflexes

involuntary motor movements initiated by specific sensory input

what is true of gray matter

it makes up the oter tissue layer in the brain

what is the correct pathway by which sound is transmitted between the ossicles of the middle ear

malleus, incus, stapes

Why can we administer ivermectin to mammals if ivermectin works as an inhibitor to parasites?

mammals have a blood-brain barrier that prevents ivermectin from reaching target receptors on cells within the brain; however, insects and parasites do not have such a barrier, so the ivermectin can readily reach target receptors throughout the nervous system

what supplies a rich network of blood vessels that supply nutrients and oxygen to the superficial tissues of the brain and spinal cord

meninges

Efferent nerves are also called _________ and they carry information _________ the CNS.

motor nerves;away from

the area of the brain through which sensory signals pass to the cerebrum is called the

thalamus

ipsilateral reflex refers to

reflex where the stimulus and response are both on the same side of the body

Where are special senses located?

All located in the head

How is core temperature measured in a clinical setting?

By using a rectal thermometer

What ion must enter the terminal bouton for neurotransmitters to dump into the synaptic cleft?

Calcium ions

What are the three parts of a neuron?

Central cell body (soma), dendrites, and axons

What are the four parts of the brain? What is the function of each part?

Cerebrum: receives and interprets sensory information, initiates conscious (voluntary) nerve impulses to skeletal muscles, and integrates neuron activity that is not normally associated with communication, expression of emotional responses, learning, memory and recall, and other behaviors associated with conscious activity Cerebellum: allows the body to have coordinated movement, balance, posture, and complex reflexes Diencephalon:serves as a nervous system passageway between the primitive brain stem and the cerebrum Brain stem: maintain basic support functions of the body, operates at the subconscious level. heavily involved in autonomic control functions related to the heart, respiration, blood vessel diameter, swallowing, and vomiting.

What neuron process receives information and which sends out information?

Dendrites: receive stimuli from other neurons and conduct the stimulus to the cell body Axons: conduct nerve impulses away from the cell body

Explain depolarization

Depolarization is when the neuron receives external stimulus, sodium channel opens on neuron cell membrane, sodium ions flow into cells by passive diffusion

What is the difference between an excitatory and inhibitory neurotransmitter?

Excitatory neurotransmitters: usually cause an influx of sodium so that the postsynaptic membrane moves toward threshold Inhibitory neurotransmitters: move the charge within the postsynaptic cell further away from threshold (makes it more negative)

What structures are located in the external ear, middle ear, and inner ear?

External ear: Pinna, external auditory canal, and tympanic membrane Middle ear: Ossicles, eustachian tube Inner Ear: Cochlea, organ of Corti

How are smell receptors stimulated?

Hair-like processes project up from olfactory cells into the mucous layer that covers the nasal epithelium, nerve impulses are generated, travel to the brain, and are interpreted as particular smells

What is the refractory period and what are the two types of refractory period

It is a time period during which a neuron is insensitive to additional stimuli; absolute refractory period and relative refractory period

Why is saltatory conduction important to large animals?

It makes processes such as vision and fine motor control possible in larger animals

In what order are the middle ear ossicles? What structures do the two end bones rest upon?

Malleus->Incus->Stapes; the tensor tympani and the stapedius

What are the general types of stimuli and give examples of each.

Mechanical: touch, hearing, balance Thermal:hot and cold Electromagnetic: vision Chemical: taste and smell

What are the basic functional units of the nervous system and what is their support group?

Neurons; Neuroglia (glial cells)

What are neurotransmitters and how do they continue a nerve impulse?

Neurotransmitters: a chemical released by the presynaptic neuron; when the nerve impulse reaches the terminal bouton, and crosses the synaptic cleft between two neuron cells with the assistance of neurotransmitters

What is proprioception? How can this be achieved?

Sense of body position and movement, knowing where body parts are at any given time, operates at any given time

What is the olfactory sense?

Sense of smell

What is the difference between the autonomic nervous system and the somatic nervous system?

Somatic: actions under voluntary control Autonomic: controls and coordinates involuntary functions

What is the sodium-potassium pump and how does this explain why even a small imbalance of electrolytes can have detrimental effects to the body?

Specialized molecule that helps a cell maintain its resting state; imbalance will affect depolarization and repolarization

What is the "all-or-nothing principal" and how does it relate to stimuli?

Stimulus must be sufficient/strong enough to make the neuron respond and cause complete depolarization, it either completely completes the cycle or doesn't do it at all

Where are superficial and central temperature receptors located?

Superficial: in the skin Central: hypothalamus

What is the difference between the CNS and the PNS?

The CNS is composed of the brain and the spinal cord, which is found withing the central axis of the body; whereas the PNS is made up of those components of the nervous system that extend away fromt he central axis outward, toward the periphery of the body

How are vibrations carried from the tympanic membrane to the cochlea?

The ossicles link the tympanic membrane with the cochlea of the inner ear, act as a system of levers that transmit sound wave vibrations from the tympanic membrane to the cochlea

What is gustatory sense?

The sense of taste

How are neurotransmitters recycled? Which molecules break down acetylcholine and norepinephrine?

They are broken down by certain enzymes; acetylcholinesterase breaks down acetylilchone amd morepinephrine is broken down by the enzyme monoamine oxidase (MAO) and catechol-O-methyl transferase (COMT).

How do animals react to pain?

They can hide pain very well, some are very sensitive and become stressed easily whereas others are very stoic and show no issues until the problem is severe.

What is the difference between touch and pressure?

Touch: tactile sense, sensation of something being in contact with the surface of the body Pressure: the sense of something pressing on the body surface

What are the four steps of the pain process?

Transduction: conversion of a painful stimulus into a nerve impulse Transmission: conduction of nerve impulse to CNS Modulation: change nerve impulse, amplify or suppress Perception: conscious awareness of painful stimuli

What is the resting state of a neuron? Is it really resting?

When a neuron is not being stimulated; No because it is still working to maintain its resting state

Touch and pressure often operate at a nearly unconscious level. When do they operate at a conscious level?

When the contact is abrupt or severe.

Where are the structures for the auditory sense located? (which bone)

Within the temporal bones of the skull

recptors

nerve endings that detect changes in the environment

What are spinal nerves?

nerves of the peripheral nervous system that originate from the spinal cord;divided into dorsal nerve roots (sensory/afferent fibers) and ventral nerve roots (motor/efferent fibers)

calls that support neurons structurally and functionally are called

neuroglia

the basic structural and functional unit of the nervous system is the

neuron, or nerve cell

the third eyelid found in some species is referred to by which name

nictitating membrane

Can a neurotransmitter bind to any receptor on a postsynaptic membrane?

no, just like a lock requires a specific key, the postsynaptic membrane receptors are very specific about which neurotransmitters they will bind.

Which cells attribute to the myelin sheath?

oligodendrocytes in the brain and spinal cord, Schwann cells in the nerves outside the brain and spinal cord

Where are chemical taste receptors located?

on the tongue in the oral cavity, also found in the lining of the mouth and pharynx

What are nociceptors?

pain receptors

What types of organs are associated with visceral sensations?

pertaining soft internal organs: like the GI tract and portions of the urinary system

a reflex arc commonly used to assess the depth of anesthesia is the ______reflex

pupillary light

rotation of the head is detected primarily by the

semicircular canals

auditory sense

sense of hearing

olfactory sense

sense of smell

gustatory sense

sense of taste

Afferent nerves are also called________ and they carry information __________ the CNS

sensory nerves;toward

2 important types of neurons are

sensory neurons and motor neurons

What are the nodes of Ranvier?

small gaps in the myelin sheath

Explain repolarization

sodium channels shut, potassium channels open, potassium diffuses out of the cell, as this stage ends the Na and K ions revert to their original side, resting stage is restored

What is the external auditory canal?

soft membrane-lined tube

What are cranial nerves?

special set of 12 nerve pairs in the PNS that originate directly from the brain.

which receptors are involved with the proprioception sense

stretch receptors in the muscles, tendons and ligaments

What type of stimulus is associated with visceral sensations?

stretch receptors, hunger and thirst

What is the duty of the meninges?

supply nutrients and oxygen to the superficial tissues of the brain and spinal cord; provide some cushioning and distribution of nutrient for the CNS

motor neurons carry instructions from

the brain to the muscles, causing them to move.

depolarization is

the change in membrane potential that occurs when a nerve is stimulated

the peripheral nervous system is comprised of

the nerves traveling from the brain or spinal cord to the target organs and back

repolarization is

the reestablishment of normal resting membrane potential

What is a terminal bouton?

the slightly enlarged bulb on each end of telodendron, contains mitochondria and neurotransmitters

What is the eustachian tube?

the tube that connects the middle ear cavity with the pharynx

what is a visceral sense

thirst

The sympathetic nervous system is also known as the ___________ because its nerves emerge from the thoracic and lumbar vertebral regions.

thoracolumbar system

What does saltare mean?

to leap

the tactile sense is the sense of

touch

sensory neurons carry signals of

touch, taste, etc. to the brain

the primary purpose of a neuron is to

transmit an electrical signal that acts either to signal other neurons or to cause a change in a target organ, such as a muscle or gland

The tympanic membrane ________ when struck by sound wave vibrations.

vibrates

Conduction of the action potential can also be described as a _______ of depolarization or nerve ________,

wave;impulse

Where can nociceptors be found?

widely distributed sensory receptors inside and on the surface of the body, found almost everywhere, range from simple, free nerve endings that respond to intense stimuli of all types, to more specialized structures that detect mechanical forces, temperature, etc