WorksheetsChapter 10 Section 4 Quiz
Total questions: 13
Worksheet time: 7mins
In response to action potentials arriving along the transverse tubules, the sarcoplasmic reticulum releases
acetylcholine
sodium ions
potassium ions
calcium ions
hydrogen ions
The narrow space between the synaptic terminal and the muscle fiber is the
synaptic knob
motor end plate
motor unit
synaptic cleft
M line
After death, muscle fibers run out of ATP and calcium begins to leak from the sarcoplasmic reticulum into the sarcoplasm. This results in a condition known as
tetany
treppe
depolarization
rigor mortis
oxygen debt
In a sarcomere, cross-bridge attachment occurs specifically in the
zone of overlap
A band
I band
M line
H band
The following is a list of the events that occur during a muscle contraction. What is the correct sequence of these events?
1. Myosin cross-bridges bind to the actin.
2. The free myosin head splits ATP.
3. Calcium ion is released from the sarcoplasmic reticulum.
4. The myosin head pivots toward the center of the sarcomere.
5. Calcium ion binds to troponin.
6. The myosin head binds an ATP molecule and detaches from the actin.
1, 3, 5, 4, 6, 2
5, 1, 4, 6, 2, 3
3, 5, 1, 2, 4, 6
3, 5, 1, 4, 6, 2
1, 4, 6, 2, 3, 5
When acetylcholine binds to receptors at the motor end plate, the sarcolemma becomes
more permeable to sodium ions.
less permeable to sodium ions.
more permeable to calcium ions.
less permeable to potassium ions.
less permeable to potassium and sodium ions.
At what point during excitation contraction coupling does exocytosis play a role?
during calcium ion reuptake into the sarcoplasmic reticulum
when sodium channels open up on the motor end plate
during acetylcholine release from the synaptic terminal
when the action potential surges through the T-tubules
when ATP splits into ADP and P on the free myosin head
Synaptic vesicles contain neurotransmitters that are released by ________ when the action potential arrives.
endocytosis
apoptosis
exocytosis
hydrolysis
sodium
Communication between axons and muscle fibers occurs at specialized synapses called
nervous units
synaptic terminals
motor end plates
motor units
neuromuscular junctions
Cross bridge detachment is caused by ________ binding to the myosin head.
ATP
calcium
magnesium
acetylcholine
acetylcholinesterase
The role of acetylcholinesterase is to
bind to ligand gated sodium channels.
activate acetylcholine.
release acetylcholine into the synaptic cleft.
transport acetylcholine across the synaptic cleft.
break down acetylcholine into acetate and choline components.
Put the following events of excitation-contraction coupling in the order in which they occur.
1. Excitation
2. Sarcomere shortening
3. Generation of muscle tension
4. Neural control
5. Contraction cycle begins
6. Release of calcium ions
4,1,5,2,6,3
4,1,6,5,2,3
1,2,5,6,3,4
6,1,4,2,5,3
1,4,6,2,5,3
Put the following events of the contraction cycle in the order in which they occur.
1. Cross-bridge detachment
2. Cross-bridge formation
3. Active site exposure
4. Myosin reactivation
5. Calcium ions bind troponin
6. Myosin head pivoting
5,3,6,2,1,4
5,3,2,6,4,1
5,3,2,6,1,4
5,3,6,2,4,1
3,5,2,6,1,4
