neurons?
It depends on what the next structure is. If it is another neurone, then it is a synapse. If it is skeletal muscle, then the it is a neuromuscular junction. If it is any other type of muscle, then it is a myoneural junction.
The location where a neuron transfers an impulse to another neuron or to a muscle cell is called a synapse. At the synapse, the presynaptic neuron releases neurotransmitters that bind to receptors on the postsynaptic neuron or muscle cell, facilitating the transmission of the signal. This process is crucial for communication within the nervous system and between nerves and muscles.
A reflex is an automatic response, that protects the organism from a harmful stimulus. The receptors detect a stimulus which generates a nerve impulse along the sensory neurone to the Central Nervous System (CNS). The CNS decides the appropiate response to the stimulus. The nerve impulse then travels across a synapse to the relay neurone, across another synapse to the motor neurone to the effector. This is normally a muscle or an organ which moves or responds to bring about a response appropiate to the stimulus.
Acetylcholine is the chemical that crosses the synapse causing a muscle to contract. It is released due to an electrical impulse sent from your brain down your nervous system.
A synapse in a simple reflex action is a junction between two neurons where signals are transmitted. In a reflex action, when a stimulus triggers a sensory neuron, it sends a signal across a synapse to a motor neuron, which then causes a rapid response from a muscle or gland.
Impulse conduction refers to passage of impulse within the same cell. Where as transmission as the name implies, is concerned about passage of impulses either chemical or electrical from one cell to another.
No, the impulse traveling down the axon ends at the axon terminal but causes the axon terminal to release neurotransmitters. The neurotransmitters diffuse across the synaptic cleft causing the sarcolemma of the muscle to initiate its own impulse.
In muscle contraction and impulse conduction, important ions include calcium (Ca2+), sodium (Na+), and potassium (K+). Calcium plays a key role in triggering muscle contraction by binding to troponin, sodium influx starts the action potential at the synapse, while potassium efflux helps repolarize the membrane after the action potential passes.
The NeuronThe cells that carry information through your nervous system are called neurons, or nerve cells. The message that a neuron carries is called a nerve impulse. The Structure of a Neuron:The structure of the neuron enables it to carry nerve impulses. A neuron has a large cell body that contains the nucleus, threadlike extensions called dendrites, and an axon. The dendrites carry impulses toward the neuron's cell body. The axon carries impulses away from the cell body. Nerve impulses begin in a dendrite, move toward the cell body, and then move down the axon. A neuron can have many dendrites, but it has only one axon. An axon, however, can have more than one tip, so the impulse can go to more than one other cell. Axons and dendrites are sometimes called nerve fibers. Nerve fibers are often arranged in parallel bundles covered with a connective tissue, something like a package of uncooked spaghetti wrapped in cellophane. A bundle of nerve fibers is called a nerve.Kinds of Neurons:Three kinds of neurons are found in the body-- sensory neurons, interneurons, and motor neurons.A sensory neuron picks up stimuli from the internal or external environment and converts each stimulus into a nerve impulse. The impulse travels along the sensory neuron until it reaches the interneuron, usually in the brain or spinal cord. An interneuron is a neuron that carries nerve impulses from one neuron to another. Some interneurons pass impulses from sensory neurons to motor neurons. A motor neuron sends an impulse to a muscle or gland, and the muscle or gland reacts in response.How a Nerve Impulse TravelsThe Synapse:What happens when a nerve impulse reaches the axon tip at the end of a neuron? At that point, the impulse can pass to the next structure. Sometimes the structure is a dendrite of another neuron. Other times, the structure is a muscle or a cell in another organ, such as a sweat gland. The junction where one neuron can transfer an impulse to another structure is called a synapse. (SIN aps). How an Impulse is Transferred:For a nerve impulse to be carried along at a synapse, it must cross the gap between the axon and the next structure. The axon tips release chemicals that carry the impulse across the gap.You can think of the gap at a synapse as a river, and an axon as a road that leads up to the riverbank. The nerve impulse is like a car traveling on the road. To get to the other side, the car has to cross the river. The car gets on a ferry boat, which carries it across the river. The chemicals that the axon tips release are like the ferry, carrying the nerve impulse across the gap.
When a nerve impulse reaches the end of a motor neuron, it triggers the release of neurotransmitters into the synapse. These neurotransmitters bind to receptors on the muscle fiber, causing a change in membrane potential that eventually results in muscle contraction. This process allows for the transmission of signals from the nervous system to the muscular system, enabling movement and coordination.
When the electrical impulse from a nerve stops, the muscle relaxes and returns to its resting state. This is because the nerve impulse initiates the release of calcium ions in the muscle cells, leading to muscle contraction. When the nerve impulse stops, the calcium ions are reabsorbed, causing the muscle to relax.
This is the neuromuscular junction. The action potential travels down the presynaptic motor neuron, releasing acetylcholine (ACh), which cross the synapse (neuromuscular junction), to bind to receptors on the end plate of muscle fibers, which induces depolarization, causing the muscle to contract.