The nervous system
How many pairs of cranial nerves do dogs have?
12
An action potential can be described as?
A large change in electrical charge from negative to positive inside the cell.
Which neurotransmitter is released at the post-ganglionic synapse of parasympathetic nerves?
Acetylcholine
Which neurotransmitter is released at the postganglionic synapse of parasympathetic nerves?
Acetylcholine
A stimulated neuron will respond by sending a wave of electrical activity down the length of the axon. This response is called a(n):
Action potential
Sensory nerves are considered:
Afferent, they carry impulses towards the CNS
Spinal nerves are what type of nerve?
All spinal nerves have MIXED nerve functions they're motor and sensory nerves, afferent & efferent
Functions that an animal does not have to consciously control, such as peristalsis in the intestine, are influenced by the?
Autonomic nervous system, we don't think about it
Define vagus nerve:
CN X, provides parasympathetic innervation to most thoracic and abdominal viscera. The viscera of the body; controls smooth muscle, cardiac muscle, and glands.
The part of the CNS that controls coordinated movement, balance, and posture is the?
Cerebellum
The centers of higher learning and intelligence are found in the?
Cerebrum
What structure acts as a light receptor?
Cone
What are the effects of parasympathetic nervous system stimulation on the heart?
Decreased rate and decreased force of contractions
Which of the following statements is true regarding the sensation of touch?
Different kinds of specific touch and pressure receptors produce sensations of light contact, deep pressure, vibration, or hair movement.
Many neurotransmitters are broken down by?
Enzymes
The neurotransmitter that is most responsible for the "flight or fight" reaction is:
Epinephrine/Adrenaline
Efferent nerves carry nerve impulses
From the body to the central nervous system carry nerve impulses away from the central nervous system. They carry the impulses to muscles and organs. Motor nerves, which are made up of a chain of motor neurons, are efferent nerves. They originate in the spinal cord and innervate muscles
OUTSIDE OF THE BRAIN & SPINAL CORD, nerve cell bodies are usually found in clumps or aggregations called:
Ganglia
Increasing a neuron's permeability to Na+ will cause?
Hyperexciteability
Efferent neurons are part of what system?
Motor nerves that are part of the somatic nervous system, they transmit impulses from the CNS out to the peripheral organs to cause an effect or action
In the stretch reflex, this structure is stretched and sends impulses via the somatic sensory neuron to the spinal cord:
Muscle spindle
elect the term that best defines insulating lipid layer covering some neurons in the brain and spinal cord and most peripheral nerves?
Myelin, fat that makes electrical currents in cells faster
The plasma membrane of the neuron in the resting state (electrically polarized) is very permeable to K+ but is almost impermeable to:
NA+/ sodium
Cells that support neurons structurally and functionally are called?
Neuroglia
Which of the following can activate the sympathetic portion of the autonomic nervous system?
Painful stimuli
What ion is responsible for repolarization of a neuron during an action potential?
Potassium Ion, Repolarization is caused by the closing of sodium ion channels and the opening of potassium ion channels.
Somatic reflex arcs involve:
Skeletal muscle
Input from what system causes vasoconstriction during exercise and therefore an increase in blood pressure?
Sympathetic nervous system
What system is anatomically composed of the brain and spinal cord?
The CNS
Select the term that best defines the space within the vertebral canal and outside of the dura mater:
The EPIDURAL, its the space above the Duramater in our spinal cord system, where they'll inject the epidural for pregnant women in pain during labor
Which of these is not one of the three major subdivisions of the brain?
The Occipital lobe
A reflex arc commonly used to assess the depth of anesthesia is?
The Pupillary light reflex arc
The electrical difference in charges across a neuron cell membrane is:
The RESTING MEMBRANE POTENTIAL, the sodium-potassium pump maintains the resting potential of a neuron.
Select the term that best defines part of the autonomic nervous system with "fight or flight" function, increase RR and HR, decrease digestion:
The Sympathetic Nervous System
When a sodium ion is rushing into a nerve cell, the cell is unable to produce another action potential regardless of how strong a stimulus is applied. This time is called the?
The absolute refractory period
Homeostasis or homeokinesis is the chief role of what part of the nervous system?
The autonomic nervous system, we do it without thinking about it.
Nociceptors are not found in this organ:
The brain
The most primitive part of the CNS is the?
The brain stem, higher learning is in the cerebrum and for the cerebellum/coordination/balance
Select the term that best defines "horses tail", terminal (caudal) portion of the spinal cord:
The cauda equina
What structure, whose Latin name means "little brain," is located at the caudal part of the brain and contains over half of the brain's nerves?
The cerebellum
An example of an action controlled by the somatic nervous system is
The head turning, somatic/conscious
What portion of the ear is essential for hearing and equilibrium?
The inner ear
Which of the following is true?
The parasympathetic preganglionic neuron travels directly from the CNS to its target organ, where it synapses with a short postganglionic neuron.
What division of the nervous system contains the cranial nerves and paired spinal nerves?
The peripheral nervous sytem outside the brain, cranial and spinal nerves.
Select the term that best defines major peripheral nerve of the hind limb coursing caudal to the femur
The sciatic nerve
During the relative refractory period, the cell may depolarize if?
The stimulus is larger than normal
What structure is not part of a nerve cell?
The stoma
What nerve (one of the longest in the body) supplies parasympathetic fibers to the heart and lungs and to nearly all of the abdominal viscera?
The vagus X/10
Afferent neurons are part of what system?
They're SENSORY neurons, part of the ANS
Which cranial nerve carries impulses from the ear to the brain?
Viii/8 The acoustic
The autonomic nervous system is directly responsible for innervation of
Visceral nerves
The vagus nerve is cranial nerve?
X- 10
Select the term that best defines Sensations from the gastrointestinal tract are provided by this nerve(hint: think parasympathetic)
X/10 cranial nerve the "vagus" nerve
Which cranial nerve innervates the throat area and the heart?
X/10 the vagus nerve
Which cranial nerve provides parasympathetic innervation to the cranial three quarters of the body?
X/10th nerv the "vagus" nerve
Of the 12 cranial nerves, which is a motor nerve to muscles in the shoulder and neck?
Xi/11 The Accessory nerve
An action potential can be described as?
a large change in electrical charge from negative to positive inside the cell
What is the result of a normal palpebral reflex?
a light tap on the medial canthus of the eye produces a blink of its eyelid.
The presence of a myelin sheath on an axon tends to?
accelerate all impulses
Select the term that best defines a neuron sending impulses toward the CNS
afferent
The "all-or-nothing" principle means?
an entire neuron depolarizes to its maximum strength.
The efferent processes of a nerve cell are the
axons
The efferent processes of a nerve cell are the?
axons, they move impulses away toward the synapse
Soma is another term for?
body
The central nervous system encompasses what subdivisions?
brain & spinal cord
The cranial nerves originate from the?
brainstem
An influx of _____ into the synaptic knob results in the fusing of vesicles containing neurotransmitters with the knob's cellular membrane.
calcium
The blood-brain barrier is found in the?
capillaries
Cerebrospinal fluid is found in the?
central canal of spinal cord
Branch like structures that conduct impulses toward the nerve cell body are called
dendrite
Nerve cells receive stimuli or impulses through?
dendrites
Which of the following is NOT a response of increased stimulation to the parasympathetic division of the autonomic nervous system?
dilation of the bronchioles
What is the name of cranial nerve VII?
facial nerve
Core temperature receptors are located in the
hypothalamus
What structure is not found in the brainstem?
hypothalamus
Which of the cranial nerves listed below has a sensory function only?
i/1 the optic cranial nerve
Cranial nerves are unique in that some are responsible for performing multiple functions. Which cranial nerve has multiple functions?
iii- Occulo, V -Trigemenal, Vii- facial, iX- Glossopharyngeal, X- Vagus
This tissue transmits information around the body and controls body functions:
nervous tissue
The type of cell responsible for the transmission of impulses through the nervous system is the
neurons, associative/connecting neurons are responible for carrying impulses from neuron to neuron
Select the term that best defines part of the autonomic nervous system with "rest and digest" function, decrease RR and HR, increase digestion?
parasympathetic
The cranio-sacral division of the autonomic nervous system is also known as the:
parasympathetic nervous system
Define parasympathetic
part of the autonomic nervous system with "rest and digest" function, decrease RR and HR, increase digestion
Define parasympathetic:
part of the autonomic nervous system with "rest and digest" function, decrease RR and HR, increase digestion
During repolarization:
potassium ions move into the cell
Select the term that best defines the sense of position and movement of the body
propioception
Select the term that best defines the sense of position and movement of the body.
propioception
The sympathetic nervous system causes?
pupil dilation
Which clinical sign is characteristic of the parasympathetic nervous system stimulation?
reduced heart rate
The most distal part of the digestive tract and most of the urogenital system are supplied with fibers from what portion of the parasympathetic nervous system?
sacral
Select the term that best defines major peripheral nerve of the hind limb coursing caudal to the femur:
sciatic nerve
Which of the following cranial nerves is assessed when testing a dog's palpebral reflex?
sensory/motor, CN V/5 Trigemenal & CN Vii/7 Facial
Nerve cells conduct electricity with rapid changes in membrane permeability to these two ions:_________ and _________. :
sodium and potassium
What happens within the neuron that allows local anesthetics to be effective?
sodium channels become blocked
Select the term that best defines the ridges and grooves of the cerebral cortex:
sulci/gyri
Input from what system causes vasoconstriction during exercise and therefore an increase in blood pressure?
sympathetic nervous system
The fight-or-flight response to an emergency situation is a specific function of the?
sympathetic nervous system
The autonomic nervous system is divided into two main divisions: the _____ and the _____:
sympathetic, and parasympathetic
The point at which the axon of one neuron meets the dendrite of another and over which nerve impulses can pass is called a:
synapse
The space between a neuron and a target cell is called the?
synapse
The space between the nerve end and the sarcolemma of the muscle is called the
synaptic cleft
The electrical difference in charges across a neuron cell membrane is?
the resting membrane potential
During the relative refractory period, the cell may depolarize if?
the stimulus is larger than normal