The Sympathetic Nervous System (Sns) Quiz Questions

The sympathetic nervous system is responsible for preparing the body for the "fight-or-flight" response. This response involves increasing heart rate, dilating blood vessels, and releasing stress hormones, all of which help the body to respond to a perceived threat or danger.

The "resting and digesting" division of the autonomic nervous system is the parasympathetic division. This division is responsible for promoting relaxation and conservation of energy in the body. It helps regulate processes such as digestion, urination, and sexual arousal. It works in opposition to the sympathetic division, which is responsible for the "fight or flight" response in the body.

A beta-blocker is a drug that can be used to specifically reduce heart rate in cardiac patients. Beta-blockers work by blocking the effects of adrenaline on the beta receptors in the heart, which in turn reduces the heart rate. This can be beneficial for cardiac patients as it helps to decrease the workload on the heart and improve its overall function. Norepinephrine and epinephrine are both hormones that can increase heart rate, so they would not be used to reduce heart rate in cardiac patients. Anti cholinesterase drugs work by inhibiting the breakdown of acetylcholine, which can lead to an increase in heart rate, so they would also not be used to specifically reduce heart rate in cardiac patients.

The hypothalamus is responsible for controlling temperature regulation, endocrine activity, and thirst. It acts as a control center for maintaining homeostasis in the body by regulating various bodily functions, including body temperature, hormone secretion, and fluid balance. The hypothalamus receives information from the body and initiates appropriate responses to maintain a stable internal environment. This makes the hypothalamus the correct answer for the given question.

Sympathetic division stimulation causes increased blood glucose, decreased GI peristalsis, and increased heart rate and blood pressure.

Over 90% of all parasympathetic fibers are derived from cranial nerve number X, also known as the vagus nerve. The vagus nerve is the longest cranial nerve and it innervates various organs in the body, including the heart, lungs, and digestive system. It plays a crucial role in regulating the parasympathetic nervous system, which is responsible for rest and digest activities. Therefore, it can be concluded that the correct answer is X.

Skeletal muscle is not directly controlled by the autonomic nervous system. The autonomic nervous system is responsible for regulating involuntary bodily functions, such as heart rate, digestion, and glandular secretion. However, skeletal muscle is under the control of the somatic nervous system, which is responsible for voluntary movements. Therefore, skeletal muscle is not directly influenced by the autonomic nervous system.

Beta-blockers are a class of medications that work by blocking the effects of adrenaline on the body. By doing so, they can decrease heart rate and blood pressure. This can be beneficial for individuals with conditions such as high blood pressure or certain heart conditions. By reducing the workload on the heart, beta-blockers can help to lower blood pressure and decrease the heart rate, leading to a more stable cardiovascular system.

Dilation of the pupils is not a result of parasympathetic stimulation. Parasympathetic stimulation causes constriction of the pupils, known as miosis, while sympathetic stimulation causes dilation of the pupils, known as mydriasis.

The vagus nerve is the correct answer because it is responsible for carrying the majority of parasympathetic outflow from the head. The vagus nerve originates in the brainstem and travels down through the neck and thorax, innervating various organs including the heart, lungs, and digestive system. It plays a crucial role in regulating functions such as heart rate, breathing, and digestion. The sympathetic trunk, phrenic nerve, and sacral nerve are not primarily involved in parasympathetic outflow from the head.

The secretions of the adrenal medulla act to supplement the effects of sympathetic stimulation. The adrenal medulla is part of the sympathetic nervous system and releases hormones such as adrenaline and noradrenaline in response to stress or danger. These hormones enhance the effects of sympathetic stimulation by increasing heart rate, blood pressure, and the release of glucose into the bloodstream. This helps prepare the body for a "fight or flight" response, enabling it to respond quickly and effectively to stressful situations.

Sympathetic responses generally are widespread because NE and epinephrine are secreted into the blood as part of the sympathetic response. These neurotransmitters are released from the adrenal medulla and are able to circulate throughout the body via the bloodstream. This allows them to reach various target organs and tissues, resulting in a widespread physiological response. Additionally, NE and epinephrine have a longer duration of action compared to other neurotransmitters, allowing for a sustained sympathetic response.

The vagus nerve is responsible for innervating various organs in the body, including the kidneys, gallbladder, and pancreas. However, it does not innervate the parotid gland. The parotid gland is innervated by the glossopharyngeal nerve, which is a separate cranial nerve.

The hypothalamus is responsible for integrating and regulating various autonomic functions, including those related to emotions. It plays a crucial role in coordinating the body's response to emotional stimuli by controlling the release of hormones, such as adrenaline and cortisol, which are involved in the fight-or-flight response. Additionally, the hypothalamus is connected to other brain regions involved in emotional processing, such as the amygdala, allowing for the integration of emotional information and the generation of appropriate autonomic reactions.

The sympathetic nerves are part of the autonomic nervous system and are responsible for the body's fight or flight response. These nerves leave the spinal cord at specific levels called ganglia. The ganglia associated with the sympathetic nerves are located along the length of the spinal cord, with the first thoracic vertebra being the level at which the first ganglia is found. Therefore, the sympathetic nerves may leave the spinal cord at the first thoracic vertebra.

The ANS, or autonomic nervous system, is a division of the peripheral nervous system that controls involuntary bodily functions. It consists of two main branches: the sympathetic nervous system and the parasympathetic nervous system. The ANS regulates various processes such as heart rate, digestion, and breathing. It does not directly innervate skeletal muscle cells, which are controlled by the somatic nervous system. Therefore, the statement "a system of motor neurons that innervates all muscle cells" does not describe the ANS.

The celiac plexus is not a plexus of the vagus nerve. The vagus nerve primarily innervates the heart, lungs, and esophagus, but it does not directly innervate the celiac plexus. The celiac plexus is a network of nerves located around the celiac artery in the abdomen, and it primarily innervates the abdominal organs such as the stomach, liver, and intestines.

The correct answer is "those that pass through the trunk ganglion to synapse in collateral or pre vertebral ganglia". The splanchnic nerves are a group of sympathetic nerves that carry fibers from the sympathetic chain ganglia to the collateral or pre vertebral ganglia. These fibers do not synapse in the same trunk ganglion they entered or with parasympathetic fibers. Additionally, they are not involved in synapsing with somatic fibers.

The parasympathetic functions include lens accommodation for close vision. This means that when the parasympathetic nervous system is activated, it causes the lens of the eye to change shape in order to focus on nearby objects. This is a normal physiological response that allows us to see clearly at close distances.

The parasympathetic fibers of the oculomotor nerves innervate smooth muscles of the eye that cause the lenses to bulge to accommodate close vision.

Autonomic dysreflexia involves the uncontrolled activation of autonomic neurons. Autonomic dysreflexia is a condition that occurs in individuals with spinal cord injuries, where there is an abnormal response of the autonomic nervous system. This leads to a sudden and potentially dangerous increase in blood pressure, which can be triggered by various stimuli below the level of injury. The uncontrolled activation of autonomic neurons is responsible for the symptoms experienced during autonomic dysreflexia, such as severe headache, flushing, sweating, and bradycardia.

The white rami communicantes are a part of the autonomic nervous system and are responsible for carrying preganglionic axons to the sympathetic chain. These axons are myelinated, which allows for faster transmission of signals. The sympathetic chain is a series of ganglia that run parallel to the spinal cord and is involved in the fight or flight response. By carrying preganglionic axons to the sympathetic chain, the white rami communicantes play a crucial role in transmitting signals from the central nervous system to the peripheral organs and tissues.

The sympathetic division of the autonomic nervous system originates from the thoracolumbar region of the spinal cord, while the parasympathetic division originates from the craniosacral region. Therefore, the statement "Sympathetic origin is craniosacral; parasympathetic is thoracolumbar" is not true.

Raynaud's disease is a condition that is characterized by exaggerated vasoconstriction in the extremities. This means that the blood vessels in the fingers and toes narrow more than usual in response to cold temperatures or stress. This can result in a lack of blood flow to these areas, causing them to turn white or blue and feel numb or cold. It is not induced by heat stress, occurs primarily in association with injury to the spinal cord, or is frequently life-threatening.

The correct answer is that erection of the penis or clitoris is primarily under parasympathetic control. This means that the parasympathetic nervous system, which is responsible for rest and digest functions, plays a major role in causing and maintaining an erection. Parasympathetic activation leads to the release of nitric oxide, which causes smooth muscle relaxation and increased blood flow to the genital area, resulting in an erection. Sympathetic activation also contributes to the process, but the parasympathetic system is the primary controller of penile and clitoral erection.

The ciliary ganglion is the correct answer because it is the parasympathetic ganglion that serves the eye. The ciliary ganglion is located behind the eye and is responsible for controlling the muscles that control the shape of the lens, the size of the pupil, and the production of tears. It receives parasympathetic fibers from the oculomotor nerve and sends out postganglionic fibers to the eye. The other options listed, submandibular ganglion, pterygopalatine ganglion, and otic ganglion, do not serve the eye and are involved in different functions of the head and neck.

The sympathetic division of the autonomic nervous system is responsible for the "fight or flight" response in the body. It activates the release of adrenaline and noradrenaline, which leads to an increase in heart rate and force of contraction, as mentioned in the first option. It also causes constriction of most blood vessels, which helps redirect blood flow to the vital organs and muscles, as mentioned in the third option. However, the sympathetic division does not cause dilation of the blood vessels serving the skin and digestive viscera, as mentioned in the second option. Instead, it diverts blood away from these areas to prioritize blood flow to the skeletal muscles, which is mentioned in the fourth option.

Once a sympathetic preganglionic axon reaches a trunk ganglion, it can ascend or descend the trunk to synapse in another trunk ganglion, pass through the trunk ganglion without synapsing with another neuron, and synapse with a ganglionic neuron in the same trunk ganglion. However, sympathetic and parasympathetic neurons do not synapse with each other within the same trunk ganglion. Therefore, the correct answer is "synapse with a parasympathetic neuron in the same trunk ganglion."

In aging, autonomic inefficiency is often due to clogging of preganglionic axon terminals with filaments. As individuals age, there can be an accumulation of filaments in the axon terminals, which can lead to a decrease in the efficiency of the autonomic nervous system. This can result in various symptoms such as impaired regulation of blood pressure, heart rate, and digestion.

The fibers that enter and leave the sympathetic chain without synapsing form structures called splanchnic nerves. These nerves are responsible for carrying sympathetic fibers to the viscera and other organs in the body. Unlike the white and gray rami communicantes, which are involved in the communication between the spinal nerves and the sympathetic chain, the splanchnic nerves have a direct connection to the organs they innervate.

Biofeedback is a technique that allows individuals to gain control over their autonomic responses by providing them with real-time information about their bodily functions, such as heart rate or muscle tension. Through this process, individuals can learn to regulate their physiological responses, such as reducing stress-induced hypertension or managing nightmares. Split brain studies, on the other hand, investigate the functional differences between the brain's hemispheres and do not directly demonstrate control over autonomic responses. Therefore, the correct answer is biofeedback.

The regulation of body temperature is a uniquely sympathetic function because it involves the activation of the sympathetic nervous system. The sympathetic nervous system is responsible for the "fight or flight" response and plays a crucial role in maintaining homeostasis in the body. When the body temperature rises, the sympathetic nervous system increases blood flow to the skin, stimulates sweat glands, and dilates blood vessels to release heat. Conversely, when the body temperature drops, the sympathetic nervous system constricts blood vessels and stimulates shivering to generate heat. This unique involvement of the sympathetic nervous system distinguishes the regulation of body temperature as a sympathetic function.

Visceral reflex arcs involve two motor neurons, whereas somatic arcs only involve one. This means that in visceral reflex arcs, there is an additional motor neuron that connects the integration center to the effector organ or gland. This allows for more complex and coordinated responses in the autonomic nervous system, which controls involuntary bodily functions.

The smooth muscle of the digestive viscera, which includes the organs of the digestive system, is primarily innervated by the tenth cranial nerve, also known as the vagus nerve. The vagus nerve plays a crucial role in regulating the function of the digestive system by controlling the movement and contraction of the smooth muscle in the gastrointestinal tract. It helps in promoting digestion and absorption of nutrients, as well as regulating the release of digestive enzymes and hormones.

The somatic and autonomic nervous system differ in their efferent pathways, target responses to neurotransmitters, and effectors. However, they do not differ in terms of all of the neurotransmitters. This implies that both systems may use some of the same neurotransmitters in their functions.

The parasympathetic tone refers to the level of activity of the parasympathetic nervous system, which is responsible for the body's rest and digest response. This tone helps regulate the normal activity of the urinary tract, ensuring proper functioning and control of urinary processes such as urine production and bladder emptying.

Autonomic ganglia are clusters of nerve cell bodies that are part of the autonomic nervous system. They are responsible for transmitting signals between the central nervous system and the visceral effectors they serve, such as the smooth muscles of organs and glands. Therefore, it makes sense to find an autonomic ganglion close to the visceral effectors they serve, which is the explanation for the correct answer "close to the visceral effectors they serve".

Autonomic ganglia contain the cell bodies of motor neurons. These motor neurons are responsible for transmitting signals from the central nervous system to the effector organs. The autonomic ganglia act as relay stations, where the preganglionic fibers synapse with the postganglionic fibers, allowing for the transmission of signals to the effector organs.