Question

Activity 1 Using the list of (10) events for muscle contraction. match the numbers of the...

Activity 1

  • Using the list of (10) events for muscle contraction. match the numbers of the steps from with the correct periods below in which they would occur.
  • Latent period:
  • Contraction period:
  • Relaxation period
  • Hint- 10 events of muscle contraction
  • 1. Action potential (electrical stimulation) from somatic (motor) nerve stimulates skeletal muscle fibers (cells) at neuromuscular junction
  • 2.“AP” causes the opening of Na+ channels on the sarcolemma thus causing a wave of depolarization to travel from the neuromuscular junction.
  • 3. Depolarization event is communicated deep into the sarcoplasm via t-tubules.
  • 4. Depolarization of sarcoplasmic reticulum causes the opening of Ca2+ channels and the subsequent release of calcium from sarcoplasmic reticulum
  • 5. Calcium binds to troponin, troponin molecules change shape causing tropomyosin to move off of crossbridge binding sites on actin
  • 6. Myosin crossbridges bind to crossbridge binding sites on actin
  • 7. ATPase acts on ATP in the binding site on the myosin to convert it into ADP + Pi + ENERGY
  • 8.Released kinetic energy causes a “power-stroke” which causes actin to slide over myosin (i.e. a contraction occurs)
  • 9. Sarcolemma repolarizes due to the opening of potassium channels.
  • 10.Calcium channels close and an active transport pump carries calcium back to sarcoplasmic reticulum, troponin returns to pre-calcium shape, and ATP reforms to release the actin-myosin bond
Science   Anatomy-And-Physiology   
0 0
Add a commentTranscribed image text
Next >

Homework Answers

Answer #1

ANSWER: LATENT PERIOD: Action potential from the somatic nerve reaches the skeletal muscle fibres at the neuromuscular junction. action potential causes openong of sodium channels and causes depolarisation. This depolarisation is communicated deep into the sacroplasm. Depolarisation of sarcoplasmic reticulum causes the relase of calcium ions. Calcium binds to troponin and exposes the binding sites of actin.

CONTRACTION PERIOD: Mysoin cross bridges are formed with the actin. ATPase converts the ATP to ADP and energy. The released kinetic energy is utilised for the power stroke which results in the shortening of muscle fibres.

RELAXATION PERIOD: Sarcolemma repolarises die to opening of potassoum channels. Calcium channels close and an active transport pump carries back the calium to the sarcoplasmic reticulum, troponin reverts back to pre calcium stage and ATP is regenerated

0 0
Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Place the following events in the correct order they occur during excitation-contraction coupling in skeletal muscle:...
Place the following events in the correct order they occur during excitation-contraction coupling in skeletal muscle: Myosin forms a tight bond with actin and undergoes the ‘power stroke’. The troponin/tropomyosin complex shifts, exposing the myosin binding sites on the actin filament. Ca2+ binds to troponin. Ca2+ moves out of the sarcoplasmic reticulum (called a “calcium spark”). An action potential in the alpha motor neuron leads to the release of neurotransmitter at the neuromuscular junction. Nicotinic receptors on the motor end...
Place the events of muscle contraction in the correct order. Selected Answer 1. ACh binds the...
Place the events of muscle contraction in the correct order. Selected Answer 1. ACh binds the nicotinic receptors at the neuromuscular juncton causing an electrical signal to develop along the muscle membrane. 2. electrical signal from the motor neuron causes the release of ACh 3. Calcium is pumped into the sarcoplasmic reticulum. 4. The signal travels into the muscle cell along the T tubules. 5. The electrical signal causes the sarcoplasmic reticulum to release calcium. 6. "Calcium binds to the...
Put the steps of muscle contraction into the correct order Troponin releases calcium and the actin...
Put the steps of muscle contraction into the correct order Troponin releases calcium and the actin binding sites are covered by the twisting of tropomyosin A stimulus from the nerve cell is brought down the T tubule Calcium is released from the SR into the cytoplasm Myosin binds to Actin Calcium is removed from the cytoplasm and actively transported to the sarcoplasmic reticulum tropomyosin untwists and exposes the actin binding sites The thin filament slides closer to the M line,...
What is the role of Ca2+ in the control of muscle contraction? a. It causes depolarization...
What is the role of Ca2+ in the control of muscle contraction? a. It causes depolarization of the T tubule system. b. It binds to tropomyosin and breaks actin–myosin cross-bridges. c. It changes the conformation of troponin, which ultimately results in myosin-binding sites being exposed. d. It changes the conformation of myosin heads, causing actin and myosin filaments to slide past each other. e. It blocks the ATP-binding site on myosin heads, enabling muscles to relax.
Part 2: Create a hand drawn diagram of the excitation-contraction coupling, beginning with the action potential...
Part 2: Create a hand drawn diagram of the excitation-contraction coupling, beginning with the action potential initiation at the neuromuscular junction and ending with sliding filament action. Be sure to include the following terms: Synaptic terminal, Synaptic Cleft, Acetylcholine, Action Potential, T-tubule, Calcium, Nicotinic Acetylcholine Receptor, Sarcolemma, Contraction, Sarcoplasmic Reticulum, Excitation, Neuromuscular Junction, Troponin, Tropomyosin, Actin, Myosin, Sodium. Potassium, Z-line
physiology of muscle contraction, select the correct description of the step from the following three options...
physiology of muscle contraction, select the correct description of the step from the following three options step 1 a. Ca moves out of the synaptic knob triggering exotyosis of acetylcholine b. Ca moves into synaptic knob, triggering exotyosis of acetylcholine c. Ca moves into synaptic knob triggering endocytosis of acetylcholine step 2. a. acetylcholine binds to CG-NA channels, Na moves into myofiber b. acetylcholine binds to CG-NA channels, Na moves out of myofiber c. acetylcholine binds to CG-NA channels, Ca...
The Myosin head pivots towards the M-line during the power stroke of muscle contraction immediately after:...
The Myosin head pivots towards the M-line during the power stroke of muscle contraction immediately after: ATP binds to the myosin head ADP and Pi fall of the head The myosin head hydrolyzes the ATP to ADP and Pi Calcium binds to troponin From Smallest to largest, which of the following is in the correct order: Myofilament, Myofibril, Myofiber Myofiber, Myofilament, Myofibril Myofiber, Myofibril, Myofilament Myofibril, Myofilament, Myofiber Which of the following is not a component of a thin filament?...
After the stimulus voltage has been applied, what events occur during the latent period? CHECK ALL...
After the stimulus voltage has been applied, what events occur during the latent period? CHECK ALL THAT APPLY. a. troponin pulls tropomyosin off the myosin binding sites of actin b. Action potentials move down a motor neuron c. tropomyosin pulls troponin off the myosin binding sites on actin d. Action potentials move down the t-tubules e. calcium binds to troponin f. ACh is released from the motor neuron g. Calcium is released from the sarcoplasmic reticulum h. calcium binds to...
I have true for all of these, please check my answers. 49. When an action potential...
I have true for all of these, please check my answers. 49. When an action potential travels down an axon to the synaptic knob of a motor neuron innervating skeletal muscle, calcium enters the synaptic knob from the extracellular fluid through electrically gated channels. The entry of the calcium into the synaptic knob results in the release of acetylcholine from synaptic vesicles. T 50. Acetylcholine released from vesicles within the synaptic knob of a motor neuron diffuses across the synaptic...
Draw a diagram! The purpose of the diagram is to show the steps from a neuron...
Draw a diagram! The purpose of the diagram is to show the steps from a neuron stimulating a skeletal muscle cell to contraction of that muscle cell. Include in your diagram: •axon terminal of motor neuron •synaptic cleft •neurotransmitter •neurotransmitter binding channels on muscle cell •t-tubules •depolarization •sarcoplasmic reticulum •receptors/channels that work together to release Ca2+ •Ca2+, Where is it? Where does it go? What does it bind to? •Sarcomeres-components (actin, myosin, tropomyosin, troponin, ATP) and how it works (sliding...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT