Which ion diffuses into the muscle fiber through the open acetylcholine receptor?

Acetylcholine is released by axon terminals of the motor neuron. When the action potential reaches the end of the axon terminal, voltage-gated sodium channels open and sodium ions diffuse into the terminal. Acetylcholine binds to its receptor in the junctional folds of the sarcolemma.

What diffuses out of the muscle fiber through open chemically gated ion channels?

ACh binds to receptors in the junctional folds. diffuses into the muscle fiber through open chemically gated ion channels. binds to ACh receptors, causing them to open chemically gated ion channels.

On what part of the sarcolemma would you expect to find acetylcholine ACh receptors?

Acetylcholine is released by axon terminals of the motor neuron. C) Acetylcholine binds to its receptor in the junctional folds of the sarcolemma. Its receptor is linked to a G protein.

Where does ACh bind in muscle contraction?

motor end plate
The acetylcholine binds to the nicotinic receptors concentrated on the motor end plate, a specialized area of the muscle fibre’s post-synaptic membrane. This binding causes the nicotinic receptor channels to open and let sodium ions enter the muscle fibre.

How is acetylcholine ACh removed from the synaptic cleft quizlet?

How is acetylcholine (ACh) removed from the synaptic cleft? simple diffusion away from the synaptic cleft and acetylcholinesterase (AChE; an enzyme)//Acetylcholinesterase breaks down acetylcholine in the synaptic cleft. The action potential on the muscle cell leads to contraction due to the release of calcium ions.

What ion diffuses into the axon terminal to stimulate the release of acetylcholine?

calcium ions
Presence of calcium ions in the axon terminal cause synaptic vesicles to fuse with the membrane. Acetylcholine is released into the synaptic cleft & calcium ions are pumped out of the axon terminal.

What binds to the ACh receptors causing them to open chemically gated ion channel?

Acetylcholine binds to the acetylcholine-gated ion channels (acetylcholine receptors [AChRs]) on the postsynaptic membrane, thereby leading to the opening of these channels and a local depolarization, the end plate potential.

How is acetylcholine ACh removed from the synaptic cleft?

What happens when acetylcholine reaches the receptors on the muscle fibers?

When acetylcholine reaches receptors on the membranes of muscle fibers, membrane channels open and the process that contracts a relaxed muscle fibers begins: Open channels allow an influx of sodium ions into the cytoplasm of the muscle fiber.

What does ACh do in muscle fibers?

ACh crosses the synaptic gap and binds to ACh receptors (AChRs) tightly clustered on the surface of the muscle fiber; this leads to the endplate potential which initiates the muscle action potential that results in muscle contraction.

Where are the acetylcholine receptors located?

muscle cells
Acetylcholine receptors are found on the surface of muscle cells, concentrated in the synapse between nerve cells and muscle cells.

What is ACh muscle contraction?

Acetylcholine is the chief neurotransmitter of the parasympathetic nervous system, the part of the autonomic nervous system (a branch of the peripheral nervous system) that contracts smooth muscles, dilates blood vessels, increases bodily secretions, and slows heart rate.

What happens when ACh binds to muscle fibers?

Once ACh binds, a channel in the ACh receptor opens and positively charged ions can pass through into the muscle fiber, causing it to depolarize, meaning that the membrane potential of the muscle fiber becomes less negative (closer to zero.)

Where are ACh receptors located in the muscular system?

ACh receptors are embedded in the sarcolemma at the neuromuscular junction. This is the neurotransmitter that is released by the terminal branches of a motor neuron. More Skeletal System Muscular System Muscle Physiology Nervous System Circulatory System Respiratory System Urinary System System Quizzes Search Home Muscle Physiology

How do sodium and potassium enter and exit the ACh receptors?

While open, the receptor (= channel) forms a temporary, water-filled pore through the sarcolemma, which allows sodium ions (= Na+) to enter a muscle fiber and potassium ions (= K+) to exit. Nicotinic ACh receptors are also known as chemical-gated or ligand-gated channels.

How does K+ diffuse into the muscle fiber?

2. diffuses into the muscle fiber through open chemically gated ion channels. 3. binds to ACh receptors, causing them to open chemically gated ion channels. 1. K+