Chapter 2: How the Divisions of the Nervous System Work Together Parasympathetic and Sympathetic Divisions Flashcards
What are the two divisions of the autonomic nervous system?
The two divisions of the autonomic nervous system are the parasympathetic and sympathetic divisions.
What is the role of the parasympathetic division?
The parasympathetic division dominates during relaxation and is sometimes called the “rest and digest” system. It lowers heart rate, stimulates digestion, and inhibits the release of stress hormones
What is the role of the sympathetic division?
The sympathetic division dominates during times of stress, fear, or anger and is sometimes called the “fight or flight” system. It increases heart rate, redirects blood flow to skeletal muscles, stimulates the release of stress hormones, promotes blood clotting, and releases glucose from the liver for energy.
How do the parasympathetic and sympathetic divisions work together?
The two divisions work together to help the body respond to perceived threats. The sympathetic division prepares the body for action during emergencies, while the parasympathetic division restores calm and normal function once the threat is resolved.
Where do nerves in the parasympathetic division originate?
Nerves in the parasympathetic division originate in the brainstem (the lowest area of the brain) and the sacral area (lowest area of the spinal cord).
Where do nerves in the sympathetic division originate?
Nerves in the sympathetic division originate from the thoracic (trunk area) and lumbar (lower back) regions of the spinal cord.
How does the frontal lobe of the brain help calm down the body’s response to perceived threats?
The frontal lobe evaluates the situation rationally and helps activate the parasympathetic division to calm down the body’s response. This can decrease heart rate, slow breathing, and relax muscles, allowing the body to return to a relaxed state.
What are some actions of the parasympathetic division on bodily functions?
Stimulates saliva production
Stimulates activity of the stomach
Stimulates bladder contractions
Stimulates activity of the intestines
Slows down the heartbeat
Constricts pupils
What are some actions of the sympathetic division on bodily functions?
Relaxes bladder
Stimulates the release of glucose
Increases the heartbeat
Dilates pupils
Inhibits activity of the stomach
Inhibits saliva production
What part of the brainstem helps regulate basic life-sustaining functions such as heartbeat and breathing?
The reticular formation, which is scattered throughout the brainstem, helps regulate basic life-sustaining functions such as heartbeat and breathing.
What is the function of the reticular formation?
The reticular formation sends messages to the rest of the brain to help maintain wakefulness and alertness, allowing individuals to concentrate on tasks such as reading.
What part of the brainstem is responsible for maintaining automatic bodily functions?
The brainstem, including the reticular formation, is responsible for maintaining automatic bodily functions such as heartbeat and breathing without conscious effort.
What cranial nerve sends the sound of shattering glass from the ears to the brainstem?
The acoustic nerve sends the sound of shattering glass from the ears to the brainstem.
Where does the message from the brainstem go next after receiving the sound?
The message from the brainstem goes to the thalamus, a large structure just above the brainstem.
What structure in the brain sounds the alarm and arouses other parts of the brain in response to danger?
The hypothalamus, located just below the thalamus, sounds the alarm and arouses other parts of the brain in response to danger.
What gland in the brain communicates with the hypothalamus and directs the secretion of hormones in response to danger?
The pituitary gland in the brain communicates with the hypothalamus and directs the secretion of hormones, primarily adrenaline and cortisol, in response to danger.
Where is the cerebellum located in the brain?
The cerebellum is located at the back of the brain, behind the cerebrum.
What is the role of the cerebellum?
helps maintain muscle tone and balance, and it coordinates muscle movements, especially during rapid or unexpected changes in position.
How did the cerebellum help when you changed position quickly from sitting to standing?
The cerebellum helped maintain equilibrium (balance) so that you didn’t fall over when changing position quickly, and it helped coordinate muscle contractions in the correct order.
What is the cerebrum, and how is it organized?
The cerebrum is the largest part of the brain and is organized into lobes, each responsible for different functions.
Which lobe of the cerebrum interprets sound?
The temporal lobes interpret sound.
Which lobe of the cerebrum creates images based on visual input?
The occipital lobe, located at the back of the brain, creates images based on visual input.
How did the frontal lobe help calm you down after seeing and hearing your cat?
The frontal lobe analyzed the meaning of the sensory messages, recognized the cat, and recalled past experiences, leading to a calming response.
How do the frontal and parietal lobes work together to coordinate movements?
The parietal lobes interpret sensory input, while the frontal lobe plans and executes movements. They communicate to coordinate movements, with messages traveling from the parietal lobes to the frontal lobe and then to the muscles through the nervous system.
The frontal lobe then sent messages to your muscles, directing their movements. Those messages first went to the thalamus, where they coordinated with impulses from the cerebellum, then to the spinal cord, then to motor neurons in the peripheral nervous system, and finally, to the muscles.
