Nervous System

Gray matter in the brain and spinal cord can be defined as billions of neuroglial nerve cell bodies and unmyelinated axons. It is responsible for processing information, including sensory perception, decision-making, and motor control.

Nerve cells, or neurons, have a unique shape with long extensions called dendrites to receive signals and an axon to transmit signals over long distances. This elongated structure allows neurons to communicate rapidly with other cells in the body. Moreover, neurons also have specialized structures called synapses that facilitate communication with other neurons or target cells.

Equilibrium and the activities of muscles and joints are monitored by proprioceptors. Proprioceptors can be found in joints and skeletal striated muscles.
proprioceptors
proprioceptors

In a myelinated fiber, voltage-regulated channels are concentrated at the nodes of Ranvier along the axon. These nodes are where action potentials are regenerated, allowing for faster conduction of the electrical signal compared to unmyelinated fibers. The initial segment before the first node acts as the trigger zone for action potential initiation.

The central nervous system (CNS) is made up of the brain and spinal cord. It is responsible for processing and integrating information from the body and coordinating responses to stimuli.

Neurons make up only about 10% of the cells in the nervous system but they play a crucial role in transmitting and processing information. Glial cells, which provide support and protection to neurons, make up the majority of cells in the nervous system.

During action potential transmission, the signal is carried along the neuronal membrane by the movement of ions such as sodium and potassium across the membrane. This movement creates changes in the membrane potential, allowing the signal to travel down the length of the neuron.

The nervous system receives information from internal body organs and external environments. Internal body organs send feedback signals about functions like heart rate and temperature, while external environments provide sensory input such as touch, sight, sound, taste, and smell.

Inhibition of parasympathetic nervous system activity causes the salivary glands to become dry or produce less saliva. This is because the parasympathetic nervous system is responsible for stimulating saliva production and secretion.

The portion of the nervous system that is most closely associated with the contraction of the cardiac muscle is the autonomic nervous system.

Bundles of neuron processes are called tracts in the cns and nerves in the pns

Epilepsy is a disorder of the nervous system characterized by recurrent seizures. Seizures occur due to abnormal electrical activity in the brain, often resulting in temporary changes in behavior, awareness, or sensation. Treatment for epilepsy usually involves medications, lifestyle modifications, and sometimes surgery.

Activation of the sympathetic division of the autonomic nervous system during stress can lead to symptoms such as increased heart rate, elevated blood pressure, pupil dilation, dilated airways, increased sweating, and decreased digestion. These physiological responses help prepare the body for the "fight or flight" response to perceived threats.

Nicotine stimulates the release of various neurotransmitters in the brain, particularly dopamine, which leads to feelings of pleasure and reward. It can also increase heart rate and blood pressure, as well as improve concentration and focus. Long-term nicotine use can lead to addiction and changes in brain chemistry.

The sense of touch is used when handling something. It allows us to feel the texture, weight, temperature, and shape of objects.

The somatic nervous system is a component of the peripheral nervous system. This system is responsible for voluntary movements and sensory information.

You need to get this right. This is not the place to discuss something of such great value as your eyes. A Vitamin A deficiency can cause or worsen dryness of the conjunctiva and cornea. Vitamin A deficiency can cause impaired night vision. However, to much vitamin A can be Toxic. The answer to your question is to ignore anything you read here and seek a professional opinion

A typical reflex usually takes around 150 to 300 milliseconds to occur. This includes the time it takes for the nerve signal to travel from the sensory receptor to the spinal cord and then to the muscle to produce a response.

The parasympathetic division of the autonomic nervous system is responsible for returning the body to normal resting levels after the fight or flight response. It promotes activities that occur when the body is at rest, such as digestion, and works to conserve energy.

plasma membrane is made up of phospholipids,proteins and short carbohydrate chains.still the structure not visible.so there are several models which explains arrangement of these components.the most accepted is the fluid mosaic model

Neurons can be classified structurally as either multipolar, bipolar, or unipolar. Functionally, neurons can be classified as either sensory, motor, or interneurons based on their role in transmitting and processing sensory information, controlling motor movements, or connecting neurons within the central nervous system, respectively.

Yes, endorphins are brain chemicals known as neurotransmitters. They transmit electrical signals within the nervous system.

The nervous system operates both voluntary and involuntary functions; it makes decisions consciously (such as my decision to answer your question) and also operates some bodily functions on an automatic basis, such as breathing and heartbeat, which I do not have to think about, and which continue to happen even when I am asleep.

Microglia are specialized cells found in the nervous system that perform phagocytosis. They are responsible for engulfing and digesting cellular debris, pathogens, and other harmful substances in the central nervous system.

Ipsilateral refers to structures or functions that are on the same side of the body. In contrast, contralateral refers to structures or functions that are on the opposite side of the body. These terms are commonly used to describe how neural pathways and connections function in the central nervous system.