PreAssignment #13 Somatic, Autonomic, and Sensory Nervous ...

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PreAssignment #13 Somatic, Autonomic, and Sensory Nervous Systems Name: _______________________________ Section #: _______ 1) In order for us to generate a motor response, we must first have receptors designed to detect a specific type of stimulus. About 90% of our motor responses are involuntary, using the spine and brain stem, with only about 10% requiring us to actually process the response with higher reasoning (voluntary responses using the cerebrum). The receptor types detect very different stimuli, so please define: a. nociceptors b. thermoreceptors c. mechanoreceptors d. chemoreceptors Which receptor type above is used for detecting flavors and odors? Which receptors are stimulated if I burn myself? Which receptors are stimulated if my blood pressure increases? Which receptors are stimulated if someone lightly touches my arm? 2) Motor responses are generated either in the primary motor cortex or in the hypothalamus. They then flow down through the thalamus (to route them to the correct effector) and the brainstem (to reach the spine). The 2 systems have different subdivisions, different terminal neurotransmitters, and very different uses in the body. Compare the autonomic and somatic motor systems based on the following characteristics: Motor System Generates responses originally in the? Effectors stimulated (what they control)? Two Major Divisions used? General Function (what they do)? Autonomic Somatic

Transcript of PreAssignment #13 Somatic, Autonomic, and Sensory Nervous ...

Page 1: PreAssignment #13 Somatic, Autonomic, and Sensory Nervous ...

PreAssignment #13 Somatic, Autonomic, and Sensory Nervous Systems Name: _______________________________ Section #: _______ 1) In order for us to generate a motor response, we must first have receptors designed to detect a specific type of stimulus. About 90% of our motor responses are involuntary, using the spine and brain stem, with only about 10% requiring us to actually process the response with higher reasoning (voluntary responses using the cerebrum). The receptor types detect very different stimuli, so please define: a. nociceptors b. thermoreceptors c. mechanoreceptors d. chemoreceptors Which receptor type above is used for detecting flavors and odors? Which receptors are stimulated if I burn myself? Which receptors are stimulated if my blood pressure increases? Which receptors are stimulated if someone lightly touches my arm? 2) Motor responses are generated either in the primary motor cortex or in the hypothalamus. They then flow down through the thalamus (to route them to the correct effector) and the brainstem (to reach the spine). The 2 systems have different subdivisions, different terminal neurotransmitters, and very different uses in the body. Compare the autonomic and somatic motor systems based on the following characteristics: Motor System

Generates responses originally in the?

Effectors stimulated (what they control)?

Two Major Divisions used?

General Function (what they do)?

Autonomic

Somatic

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3) The sympathetic nervous system (SNS) is often called the “fight or flight” system, while the parasympathetic division is called “rest & digest”. Their nerves innervate many of the same organs, but they have opposite effects (since their terminal neurotransmitters also differ). Acetylcholine (ACh) is released by the parasympathetic system while norepinephrine (NE) is released by the sympathetic. They also originate on the CNS differently (cranial/sacral vs. thoracolumbar). Their opposite effects are useful for lie detector tests! Describe what the two divisions do to each item listed:

Body System Affected Sympathetic Motor NS Parasympathetic Motor NS Pupil of the eye Blood flow Digestive tract Defecation/urination Bronchial size (respiration) Heart rate Liver glycogen Male reproduction

4) We store memories as neuronal patterns in the gyri (bumps) and sulci (indentations of the cerebrum). Remember, sensory memories are stored in the back of the brain and motor are stored in the front! Tell me how we use: a. short-term memory b. long-term memory c. skill memory d. fact memory What is a memory engram? What are three specific things we can do to enforce engrams?

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5) Proper amounts of both sleep and arousal are necessary for proper brain long-term function. Roughly 25% of the US adult population is believed to be sleep-deprived (a fact that likely will not surprise college students)! aa. What is the difference between REM and non-REM sleep? b. What is the RAS and how does it interact with our thalamus? c. How does serotonin influence our brain functions? d. How does norepinephrine influence our brain functions? 6) Olfaction (like gustation, or taste) uses chemoreceptors, but they are located above the nasal septum (not the oral cavity). Olfactory sensory neurons bind chemicals on their dendrites and generate APs to the brain if they pass threshold. The impulses are then processed directly by the olfactory cortex below the temporal lobes of the cerebrum and stored. Note: the thalamus is not involved unlike all other stimuli! a. Using a flow chart (A à B à C) draw the proper olfactory pathway by reordering the terms: cribriform plate, olfactory nerve, temporal lobe (of cerebrum), olfactory tract, olfactory bulb, olfactory epithelium. b. How many different chemicals can an average human detect? How about a dog? c. Why is it important that olfactory stimuli are shared with the hypothalamus and limbic system? d. What happens physiologically to our sense of olfaction with age?

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7) Gustation, or taste, provides information about the foods and liquids we eat and drink. Gustatory receptors are found in taste buds that are distributed over the top of the tongue and back of the pharynx and larynx. These receptors are stimulated by dissolved food molecules attaching to chemoreceptors. This stimulation creates action potentials that are then sent to the gustatory cortex for interpretation and memory storage. a. Why are papillae needed for our taste buds? b. Which specific cranial nerves carry gustatory information to the brain? c. Why does gustation diminish when you have a cold? d. What are the four primary tastes we interpret, and which ones are the strongest? 8) We rely more on vision than on any other special sense. Our eyes contain a retina with visual receptors called rods and cones that enable us to not only detect light, but also to create detailed visual images that we

then store as memories. In order for light to hit the retina, it must pass through a bunch of clear structures first. APs are then generated, shared between the sides, and sent to the occipital lobes of the brain for storage.

a. Using a flow chart (A à B à C) draw the proper visual pathway by reordering the following terms from cornea to brain: retina, lens, optic nerve, pupil (of iris), vitreous humor, optic chiasm, aqueous humor, and optic tract. Corneaà à à à à à à à à Occipital lobe (of Brain) b. Why do we need a lacrimal gland, sac, and duct for normal eye function? c. How do the rods and cones of the retina differ in use? d. What is glaucoma and how is it treated?

Gustatory Cortex

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9) Our inner ear contains receptors that are receptive to both motion (equilibrium) and sounds (hearing), but it is separated and protected from the environment by the middle ear and outer ear. Please label the diagram properly with the following terms: external auditory meatus, tympanic membrane, vestibule, semicircular canals, ossicles (MIS), cochlea, pinna (or auricle), Eustachian tube, and the vestibulocochlear nerve. 10) Please describe the differences in our use of: a. the oval and round windows? b. signals from the superior, posterior, and lateral semicircular canals? c. signals from the utricle and saccule of the vestibule? Now, how does our brain interpret the wavelength versus the amplitude of sounds that we hear?