Exam #3

there are fewer motor neurons than skeletal muscle fibers

Due to the pattern of innervation of skeletal muscles, one would expect that

most superficial and thickest meninix

Dura mater

is insensitive to further stimulation

During the asbolute refractory period, the cell

the production of an action potential in the sacrolemma

Excitation coupling begins with

temporal summation

If five action potentials arrive at the same synapse in very close succession, which of the following would occur?

myosin heads bind to exposed active sites on actin

In excitation coupling,

K+ tend to diffuse out of the cell

In hyperpolarization,

threshold

In order for local potentials to trigger an action potential, the membrane must reach a level called the ______

muscles of the arm and forearm

The brachial plexus supplies nerves that function to contract which of the following?

destroyed by cholinesterane

after contraction has occured, the Ca2+ are

median nerve

an injury to the wrist that results in edema in the carpal tunnel would compress the

the deltoid and teres minor muscles

axillary nerves innervates

the trigger zone

axon contains

hamstring muscles

biceps femoris is part of the

nodes of ranvier

gaps or interruptions in the mylein sheath are called

responds to stimulation by the nervous system

muscles exhibit the property of excitbility. this. means that the muscle

thick myofilament

myosin is known as the

lumbar

spinal nerve exiting the spinal cord from the level of L4 to S4 from the ______ plexus

exposure of the active sites on G actin

substance A is to be found to be a competitor with ACH. Which step of muscle contraction physiology would be directyl effected by this substance?

form the medial and lateral plantar nerves

tibial nerve branches to

from node to node on a mylenated fibers

Action potentials are conducted more rapidly when transmission is

yeilds as many as 36 ATP per glucose metabolized produces ATP molecules faster than anerobic respiration

Aerobic respiration

occurs when the local potential reaches threshold level.

An action potential

the ability of a muscle to maintain a contraction against an outside force

A proper definiton of muscle tone is

the nuueron is hyperpolarized

A series of local potentials causes the membrane potential to move to -80 mV. Predict the result

Have straitions

Cardiac muscle cells are like skeletal muscle cells in that they both

difficulty breathing

Damage to the phrenic nerve would result in

Anaroeib

Most important chemical process you need to rely on while running a 50 m dash

is a condition in which cross-bridges cannot release

Phsyiological contracture

the meninix bound tightly to brain and spinal cord

Pia mater

ACH

Synaptic vessicles in the neuromusclar junction contain

an excitory postsynaptic potential will result

When a neurotransmitter binds to its receptor and increases the permeability of the postsynaptic membrane to sodium ions,

As NA+ enter, the inside of the plasma membrane becomes more negative

Which of the following events is NOT a characteristic of action potential?

Depolarization causes voltage-gated Na+ channels to open

Which of the following situations occurs in electrically excitable cells?

Aerobic

Which skeletal muscle is producing CO2 and water while making ATP, which chemical process could be active at this time?

local

a change in resting membrane potential confined to a small area is called a/an ______ potential

innervates the anterior and lateral muscles of the leg

common fibular nerve

rotate the head toward the left

contracting the right sternocledomastoid would

extend and laterally flex the neck

contracting the trapezius muscle would

phrenic nerve

damage to which of these nerves would be most life threatening?

movement

if the ventral root of a spinal nerve were cut, the regions innervated by that spinal nerve would experience a complete loss of

contractility

the capacity of a muscle cell to shorten forcefully is known as

outside, gray matter on the inside, a ventral motor root

the cross-sectional view of the spinal cord reveals white matter on the

ventral

the motor root of a spinal nerve is also referred to as the ______ root

stores ca2+

the sarcoplasmic reticulum

tibial and common fibular nerves

the sciatic nerve is composed of

dorsal

the sensory root of a spinal nerve is also referred as _____root

dura matter

the thickest of the meninges is the

8

there are __________ cervicle spinal nerve

the movement of myosin head while attached to actin myofilament

what is a cross bridge?

repolarizing

when the voltage of a plasma membrane shifts form +35mv towards 0 mv, the neuron is ____

skeletal and cardiac

which type of muscles contain strations?