BI 207 Exam 3/ Chapter 9 Muscles
Motor neuron action potential, neurotransmitter release, muscle cell action potential, the release of calcium ions from SR, ATP-drive power stroke, sliding of myofilaments.
Which of the following is the correct sequence of events for muscle contractions?
Myofibrils
The contractile units of skeletal muscle muscles are...?
Actin and myosin sliding past each other and partially overlapping
The sliding filament model of contraction involves...?
True
True or False: The refractory period refers to when the muscle is temporarily unable to respond to stimuli?
True
True or false: The correct order for a muscle twitch is latent period, contraction, and relaxation.
False
True or false: smooth muscle contains t-tubules?
Acetylcholinesterase
What is the name of the enzyme that prevents ACh in the synaptic cleft from continuing to stimulate contraction?
Acetylcholinesterase
What is the name of the enzyme that prevents acetylcholine from continuing to stimulate in the synaptic cleft?
Actin filaments
Where will myosin attach to form cross bridges?
No muscle tension would be generated
Hypothetically, if a muscle were stretched to the point where thick and thin filaments no longer overlapped..,.
Perimysium
Identify the fibrous connective tissue surrounding muscle fascicles.
Actin
Identify the thin myofilament.
Excitability
What characteristic of muscle refers to the ability to respond to and receive stimuli?
T tubules
What feature of skeletal muscle allows electrical nerve transmissions to reach deep inside the interior muscle fibers?
Our muscles will stay contracted
What happens when there is not more ATP available for our muscles?
Calcium
What ion binds to troponin causing a conformational change in tropomyosin to uncover the myosin binding site?
Sodium
What ion diffuses across the cell membrane resulting in depolarization?
Na+
What ion is primarily responsible for depolarization?
Ca2+
What ion's intracellular concentration is regulated by the sarcoplasmic reticulum (SR)?
Relaxation
What is the final phase of a muscle twitch?
Endomysium
What is the name of the connective tissue that surrounds individual muscle fibers (cells)?
Acetylcholine
What is the primary neurotransmitter in skeletal muscle contraction?
Tropomyosin
What is the protein that serves as a contraction inhibitor by blocking the myosin binding sites on the actin molecules?
Fascicle
What is the term for a group of muscle fibers?
Sarcomere
What is the term for the smallest contractile unit of a muscle fiber? Sarcomere
A muscle will contract the most when it is at a resting length
What of the following is true of the length-tension relationship of muscle?
Wave summation
What process does the body use to create smooth and continuous contractions?
Sarcoplasmic reticulum (SR)
What structure in skeletal muscle cells function in calcium storage?
Motor neuron action potential
What will be the first step in the sequence of events?
Stability
Which of the following is NOT a characteristic of muscle?
Peristalsis
Which of the following is NOT a function of skeletal muscle?
Ferritin
Which of the following is NOT a protein of skeletal muscle?
Epimysium
Which of the following membranes surround the entire muscle?