Pre-exam #3
How many coccygeal spinal nerves are there?
1 pair
In hyperpolarization
K+ tend to diffuse out of the cell
Axillary nerve innervates the:
deltoid and teres minor muscles
What occurs in electrically excitable cells?
depolarization causes voltage-gates Na+ channels to open
A change in resting membrane potential confined to a small area is called a:
local potential
Rapid removal or destruction of neurotransmitter in the synaptic cleft
may affect the ability of the postsynaptic membrane to generate action potentials
Dura mater is the
most superficial and thicket meninx
Contracting the right sternocleidomastoid muscle would
rotate the head toward the left
spinal nerves exiting the spinal cord from the level of L4 to S4 form the
sacral plexus
Axons contain:
the trigger zone
The plasma membrane of a neuron is more permeable to K+ because
there are more leak ion channels for K+ than Na+
myosin is also known as the
thick myofilament
What is composed of myosin molecules?
thick myofilaments
In order for local potentials to trigger an action potential, the membrane must reach a level called the
threshold
The cross-sectional view of the spinal cord reveals:
white matter on the outside gray matter on the inside a ventral motor root
Aerobic Respiration
yields as many as 36 ATP per glucose molecule metabolized
Hydrocephaly is a condition whereby cerebrospinal fluid accumulates around the brain. What supportive cells continue CSF production despite it backing up in the subarachnoid space?
ependymal cells
Contracting the trapezius muscle would
extend and laterally flex the neck
Synaptic Vesicles in the neuromuscular junction contain:
acetylcholine
Synaptic vesicles in the neuromuscular junction contain
acetylcholine
The active sites to which cross-bridges attach are found on the
actin myofilaments
common fibular nerve innervates the
anterior and lateral muscles of the leg
Alex is participating in a 50-meter dash. Predict the most important chemical process his muscles will rely on during this race
both anaerobic and creatine phosphate breakdown
Spinal nerves C5-T1 make up the:
brachial plexus
tibial nerve
branches to form the medial and lateral plantar nerves
the function of acetylcholinesterase is to
break down acetylcholine in the synapse
Action potentials are conducted more rapidly when transmission is
from node to node on a myelinated axon
What is part of a thin myofilament
globular (g) actin
The biceps femoris is part of the
hamstring muscles
Troponin:
has a calcium-binding site
If the ventral root of a spinal nerve were cut, the regions innervated by that spinal nerve would experience complete loss of
movement
The brachial plexus supplies nerves that function to contract the:
muscles of the arm and forearm
A sarcomere extends from
one Z disk to an adjacent Z disk
When the myosin head flexes into a bend, pulling the actin filament along with it, this is called the
power stroke
When the myosin head flexes into a bend, pulling the actin filament along with it:
power stroke
When the voltage of a plasma membrane shifts from +35mV towards 0, the neuron is:
repolarizing
Muscles exhibit the property of excitability. This means that the muscle
responds to stimulation by the nervous system
The sarcoplasmic reticulum:
stores Ca^2+
A sarcomere is the
structural and functional unit of the skeletal muscle fiber/cell
During a spinal tap, where is cerebrospinal fluid obtain from?
subarachnoid space
The sciatic nerve is composed of the
tibial nerve and the common fibular nerve
When a person hits their "funny bone", they cause temporary damage to their>
ulnar nerve
The motor root of a spinal nerve is also referred to as the:
ventral root
Multiunit smooth muscle is located in the
wall of the GI tract
When skeletal muscle is producing CO2 and water while making ATP, which chemical processes could be active at this time?
Aerobic Respiration
How many lumbar spinal nerves are there?
5 pairs
How many sacral spinal nerves are there?
5 pairs
How many cervical spinal nerves are there?
8 pairs
Events of Synaptic Transmission in order:
1) Action potential causes release of neurotransmitter 2) Neurotransmitter diffuses across the synaptic cleft 3)Neurotransmitter binds with receptor on postsynaptic cell 4)Membrane permeability to Na+ on postsynaptic cell increases 5) Na+ diffuses into the cell and causes a local potential
How many thoracic spinal nerves are there?
12 pairs
How many total pairs of spinal nerves are there?
31 pairs
Characteristics of an action potential
At the peak of depolarization, Na+ channels begin to close and K+ channels open In repolarization, K+ flow out of the cell Action potentials occur according to the all-or-none priniciple
Frank has a microbial infection attacking his brain. What cell type would you expect to proliferate and be most active during this time?
Microglia
Damage to which of these nerves would be most life-threatening
Phrenic nerves
damage to the phrenic nerve would result in
difficulty breathing
The sensory root of a spinal nerve is also referred to as a
dorsal root
The thickest of the meninges is the:
dura mater
Epidural space separates the
dura mater from periosteum
Synapses in which gap junctions allow ions to diffuse quickly from cell to cell are called:
electrical synapses
an injury to the write that results in edema in the carpal tunnel would compress the
median nerve
Pia mater is the
meninx bound tightly to brain and spinal cord
The junction between two neurons is a:
synapse
If five action potentials arrive at the same synapse in very close succession, which of the following would occur?
temporal summation occurs
An action potential occurs when:
the local potential reaches threshold level
A series of local potentials causes the membrane potential to move to -80mV. Predict the result
the neuron is hyperpolarized
Excitation-contraction coupling begins with:
the production of an action potential in the sarcolemma