exam 2 week 4 & 5, pre-lecture quizzes Flashcards
True or False: Afferent signals move from the CNS to the periphery of the body and efferent signals move from the periphery of the body to the CNS.
False
Efferent signals move from the CNS to the periphery, while afferent signals move from the periphery to the CNS.
True or False: Spinal nerves are mixed nerves (both motor and sensory components).
True
Mixed nerves contain both afferent (sensory) and efferent (motor) fibers.
True or False: The motor fibers of spinal nerves have cell bodies in the dorsal root ganglion, while the sensory fibers have cell bodies in the ventral horn.
False
Sensory fibers have cell bodies in the dorsal root ganglion, and motor fibers have cell bodies in the ventral horn.
What are the divisions of the peripheral nervous system?
Somatic and autonomic nervous system
The somatic nervous system controls voluntary movements, while the autonomic nervous system regulates involuntary functions.
True or False: Cranial Nerves are only motor nerves
False
CNs can be motor and/or sensory nerves
What CN (name + roman numeral) innervates the muscles that move your tongue?
CN XII – hypoglossal nerve
When you taste chocolate in the front of your mouth, what CN is responsible for that?
CN VII – facial nerve
Which CN helps you chew your food?
CN V – trigeminal
If you choke on food and cough, what CN helps you cough?
CN X – vagus
Which CN helps you move your head to the right?
CN XI – accessory nerve
Which ANS system will get activated when you are startled by a friend at night?
Sympathetic nervous system
What is the role of the sodium-potassium pump in maintaining the resting membrane potential?
Pumps 2 K+ ions into the cells for every 3 Na+ it pumps out
This active transport mechanism helps to create a negative charge inside the cell.
What is the function of leaky potassium channels?
Facilitate diffusion of K+ out of the cell
These channels contribute to the resting membrane potential by allowing potassium ions to leave the cell.
What is the name of the faster conduction of signals in myelinated axons?
Saltatory conduction
This occurs because the action potential only depolarizes at the Nodes of Ranvier.
How does saltatory conduction differ from continuous conduction?
Action potential occurs only at Nodes of Ranvier instead of along the entire axon
This results in faster signal transmission in myelinated axons.
What parts of the body comprise the CNS?
Brain and spinal cord
The CNS is responsible for processing and transmitting information.
What parts comprise the PNS?
Nerves and ganglia
The PNS connects the CNS to the rest of the body.
afferant signals
sensory signals
move information from PNS to CNS
efferent signals
motor signals
move information from CNS to PNS
True or false: The neuromuscular junction is the place where the motor neuron dendrites synapse with muscle fibers.
False. The neuromuscular junction is the place where the motor neuron AXONS synapse with muscle fibers.
True or false: fasciculi are groups of muscle fibers bound together by epimysium.
False. Fasciculi are groups of muscle fibers bound together by ENDOmysium.
This distinction is important for understanding the organization of muscle tissue.
What are the contractile units of a muscle cell?
Sarcomeres
Sarcomeres are the fundamental units responsible for muscle contraction.
Which muscle type can be controlled voluntarily?
Striated/skeletal muscle
What neurotransmitter is in sacs in the terminal boutons of motor neurons?
Acetylcholine (ACh)
ACh plays a crucial role in transmitting signals at the neuromuscular junction.
