parasympathetic
Yes, coronary vessels have both parasympathetic and sympathetic innervation. Parasympathetic input leads to vasodilation of coronary vessels, while sympathetic input can cause vasoconstriction in response to stress or exercise. The balance between these two systems helps regulate blood flow to the heart.
Beta 2 adrenergic receptors in lung tissue cause dilation of bronchioles via sympathetic stimulation.
The autonomic nervous system is in charge of involuntary functions. There are two divisions-the sympathetic and parasympathetic. The sympathetic nervous system initiates the fight-or-flight response in emergency situations. The parasympathetic nervous system is referred to as the "rest and digest" stage in which the body "slows down" after the fight-or-flight response.
Pupillary response is controlled by the autonomic nervous system.In bright light or when looking at close objects, the parasympathetic nervous system will cause pupillary constriction by activating the sphincter pupillae muscle(s). The parasympathetic nerves that innervate the sphincter pupillae are the short ciliary nerves, which come from the ciliary ganglion in the orbit. Innervation of the ciliary ganglion is via parasympathetic pre-ganglionic fibers traveling with the occulomoter nerve from the edinger-westfall nucleus in the cranial midbrain.In low light, when looking at distant objects, or when stress levels are high (fight or flight) the sympathetic nervous system will cause pupillary dilation by activating the iris dilator muscle(s). The sympathetic nerves that innervate these muscles come from the superior cervical ganglion.
Yes, the autonomic nervous system can cause either activation or inhibition depending on whether the sympathetic division or parasympathetic division is active, and which target organ is being affected. The sympathetic division generally activates the fight-or-flight response while the parasympathetic division promotes rest and relaxation.
Yes. The vagus nerve is a parasympathetic nerve that is almost always stimulating the healthy heart to have a heart rate less than the inherent rate of the SA node. The sympathetic innervation on the heart is minimal and only important during exercise.
it can cause you to die
no
No, sympathetic activity typically causes vasoconstriction, not vasodilation.
Parasympathetic
The parasympathetic nervous system is a division of the autonomic nervous system (along with the sympathetic nervous system, and the enteric nervous system). In simple terms, the SNS can be thought of as the body's gas pedal, and the PNS as the brake. So where the SNS deals with 'fight or flight' the PNS deals with 'rest and digest'. In other words, the PNS is often inhibitory. For example, it can act to slow down heart rate, enhance the peristaltic contractions of the gut, or increase secretions of digestive enzymes. In can also cause vasodilation (make the blood vessels wider) around your gut after meals: this means more blood flows to your intestive and stomach after you've eaten a meal, allowing you to digest what you've eaten.
Yes you can. Parasympathetic rebound is a possible reaction of the parasympathetic nervous system during intense fear. It can cause death. Some soldiers literally die of fear in combat.