Exam 1 Flashcards
T or F: neurons do not physically touch one another
True
Your doctor taps on your patellar tendon. List out the steps, in detail, of the nervous pathway of the reflects he is testing. Include any sensory organs involved in the action of the reflex.
- Tapping patellar tendon causes it to stretch
- Stretch detected by muscle spindles
- Afferent neuron sent through DRG
- Passes through spinal cord
- Synapses on motor neuron
- Contracts quadriceps, kicking of foot
A postsynaptic neuron would be found:
After the synapse
This is a collection of cell bodies found in the PNS
GANGLIA
T or F: reflexes occur slower than a conscious decision to move from the brain
False
A neuron going to the bicep of the forearm is part of the:
- PNS
- SOMATIC
A patient’s spinal cord was severed in a car accident. Would the patient be expected to regrow axons in their spinal cord?
No, the spinal cord is a part of the CNS. Only PNS axons are capable of regeneration.
T or F: action potentials travel in one direction within the same neuron
 True
What neurotransmitter helps regulate emotional responses in muscle tone?
Dopamine
T or F: a sensory neuron is signaling the body of extreme pain. This means that the strength of the action potential is greater than usual. Explain your reasoning.
This is false. There is no variation in the strength of an action potential.
This part of the autonomic system increases digestion
PARASYMPATHETIC
In a reflex, the _______ neuron conducts nerve impulses along a path way towards the CNS
Sensory (afferent)
This part of a neuron conducts nerve impulses AWAY from the body
AXON
An afferret neuron carries information:
From the PNS to CNS
The ventral root of a nerve contains what type of neurons?
MOTOR (efferent)
At rest, a neuron plasma membrane is:
-70 mV
Which of the following statements is true concerning the neuromuscular junction?
The NMJ terminates on a muscle fiber
Which of the following statements is false about reflexes?
Pulling a hand away from a hot flame is not a reflex it is entirely voluntary
What is false about the flexor withdrawal reflex?
- It does not involve interneurons
- The effect of the reflex is to create a co-contraction of two muscles
What is the location and function of astrocytes?
- CNS
- Regulate chemical environment inside CNS, form a physical Blood brain barrier by wrapping around blood capillaries
Which of the following is true concerning the sodium-potassium pump?
It must remain in constant operation to maintain the resting state
What prevents continuous stimulation of a nerve synapse and how is it accomplished?
Continuous stimulation of a nerve synapse is prevented by the short existence of neurotransmitters. This is accomplished by enzymes deactivating the neurotransmitters and some enzymes absorbing the neurotransmitters.
Describe the synthesis and storage of neurotransmitters
Neurotransmitters are synthesized in the neuron cell body. They are stored in secretory vesicles at the end of axon terminals.
This part of a reflex is inside the CNS, made up of one or more synapses
Integration center
What is false about the stretch reflex?
The effect of the motor signal is to relax the muscle
Multiple sclerosis, an autoimmune disease, which attacks the myelin sheath of the nerve axon. Patients with this disease may experience difficulty using the muscles of their arms and legs. Explain why this would occur.
Multiple sclerosis affects the formation of myelin sheath. Myelin sheath main function is to increase nerve conduction speed and protect the nerve. If there is damage done to it, the conduction speed would be slow and the nerve would be vulnerable. Making it difficult for the muscles to be utilized.
This is the most superficial layer of the brain meninges
Dura Mater
The ______ fissure separates the cerebrum from the cerebellum
Transverse
What is the purpose of the blood-brain barrier? Describe its maintenance from a cellular level.
The blood-brain barrier is a diffusion barrier for the brain and spinal cord to keep certain particles out of CNS tissue. The barrier is a relatively impermeable membrane due to the formation of astrocytes. This barrier also keeps the brain and spinal cord separate from general circulation to ensure the stability of the environment. The environment for the nerves of the brain and spinal cord is important so that they do not undergo chemical variants that could cause uncontrollable, rapid firing.
All the following are functions of the hypothalamus except:
- Maintain homeostasis
- Controls the pituitary gland
- Links the nervous and endocrine systems
- Relays sensory impulses to the cerebrum
Relays sensory impulses to the cerebrum
What is the largest portion of the brain?
Cerebrum
This region of the brain controls decision making skills
Frontal Lobe
A patient is having difficulty producing speech sounds, but other motor movements are normal. Which area of the brain is most likely damaged?
Broca’s Area
Describe how memories are stored and retrieved in the brain. Include a specific brain region.
Memories are stored throughout the cerebral hemispheres. The hippocampus is especially important to storage and retrieval of memories. Along with the amygdala, a portion of the limbic system, it is how emotionally charged events are vivid in our memory.
Which statement is false concerning the brainstem?
- The medulla portion of the brainstem continuous with the spinal cord.
- The medulla contains reflex centers to regulate vasoconstriction.
- The midbrain contains the superior and inferior colliculi.
- The midbrain helps to regulate breathing.
The midbrain helps to regulate breathing
Which of the following is false concerning the cerebellum?
- The gray matter is external while the white mater is internal.
- The cerebellar peduncles are located posteriorly.
- The anterior lobe receives information from the body trunk.
- The vermis coordinates arm movements.
The cerebellar peduncles are located posteriorly
Which of the following is most likely a symptom of ALS?
- Impaired ability to swallow
- Decreased sensation in the hands
- Shrinkage of cerebral cortex
- Increased size of brain ventricles
- All the above
Impaired ability to swallow
Which of the following is true concerning a CVA?
- An ischemic stroke is also known as a “brain bleed”.
- A TIA is a form of hemorrhagic stroke.
- Stroke survivors never regain any lost function.
- A hemorrhagic stroke is due to a broken blood vessel.
A hemorrhagic stroke is due to a broken blood vessel
A patient is unable to extend his fourth and fifth digits when asked to open his hand. What is most likely the cause?
Ulnar Nerve Damage
