Chapter 14 - Chapter 14: Sense Organs 1. Why are visceral...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 14: Sense Organs 1. Why are visceral sensations important to the survival of an animal? Visceral sensations keep the CNS informed about the overall prevailing conditions inside and outside the body. The result is the initiation of behaviors designed to ensure the well-being of the animal. 2. Why do touch and pressure sensations fade so rapidly from the conscious mind unless they change or are severe? Touch and pressure sensations are not threats to the well-being of the animal and tend to fade from the conscious mind thereby allowing the CNS to focus on other, more important sensations. 3. If a dog walks out of an air-conditioned house and lies in the sun on a hot summer day, which of its temperature receptors will signal the brain first that the dog is getting hot: superficial receptors or central receptors? Superficial receptors 4. Which category of temperature receptors is most critical to the long-term survival of an animal in very hot or very cold environmental conditions: the superficial receptors or the central receptors? (Hint, which is more critical to an animal's survival, keeping its skin and extremities from getting too hot or cold or keeping the core of its body from getting too hot or cold?) Central receptors 5. What is nociception and what roles do transduction, transmission, modulation, and perception play in it? Nociception is the process of experiencing pain. Transduction is the conversion of the painful stimulus to a nerve impulse that occurs at the sensory nerve ending. Transmission of the nerve impulse up the sensory nerve fibers to the spinal cord is the next step. Modulation (changing) of the sensory nerve impulses can occur in the spinal cord, and this can significantly influence the information the brain receives, particularly in cases of chronic and/or severe pain. This modulation process can amplify (make more severe) or suppress (make less severe) sensory impulses through synapses between neurons in the dorsal horns of the spinal cord. Finally, perception of the painful impulses by several areas of the brain occurs. Conscious perception occurs in the cerebral cortex, but other areas of the brain are also involved. These include areas involved with the autonomic nervous system (fight or flight), fear and anxiety, memory, arousal, and behavior and emotion. 6. Why do you suppose mild to moderate pain often does not appear to significantly affect the mood or behavior of domestic animals? Animals do not seem to have the same kind of emotional reaction to pain that humans do. They often seem to hide it well. Hiding signs of pain is a survival instinct for most animals. An animal that shows signs of pain is showing signs of weakness that might encourage other animals, including predators, to attack it. 7.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 5

Chapter 14 - Chapter 14: Sense Organs 1. Why are visceral...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online