Explanation There are two types of photoreceptors in the retina, namely, rods and cones. These receptors process the light and help in generating nerve impulses from the light. Cones contain receptors that help to perceive colors and sharp vision and work best in the bright light. In the dim light, their response diminishes. Rods cannot detect colors. They produce low-acuity vision and are unable to function in the bright light. They are extremely sensitive to the dim light. The cones are concentrated near fovea centralis and their number decreases toward the edge of the retina. Rods are concentrated toward the edge of the retina and very few near the fovea...

Human Anatomy & Physiology (2nd Edition)

2nd Edition

ISBN: 9780134553511

Author: Erin C. Amerman

Publisher: PEARSON

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Question

Chapter 15, Problem 10CYR

Summary Introduction

To review:

The rationale behind seeing an object better in the dim light by looking at its side instead of looking directly at it.

Introduction:

To see an object better, the eyes should be focused on the object. This helps in directing the light coming from the object at fovea centralis. However, in the dim light, looking directly at an object does not make it look clear, but looking atits side presents with a better picture. This phenomenon is explained by the structure of the retina.

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Chapter 15, Problem 9CYR

Chapter 15, Problem 11CYR

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Chapter 15 Solutions

Human Anatomy & Physiology (2nd Edition)

Ch. 15.1 - What are the three major differences between the...Ch. 15.1 - What is sensory transduction?Ch. 15.2 - 1. Where is the olfactory epithelium located? Ch. 15.2 - 2. What types of cells make up the olfactory...Ch. 15.2 - Describe the structure of an olfactory neuron.Ch. 15.2 - What happens in an olfactory neuron when an...Ch. 15.2 - How can humans detect such a variety of odors with...Ch. 15.2 - Prob. 6QC Ch. 15.3 - Where are taste buds located?Ch. 15.3 - Prob. 2QC

Ch. 15.3 - Prob. 3QC Ch. 15.3 - Prob. 4QC Ch. 15.3 - How does a gustatory cell transduce a chemical...Ch. 15.3 - 6. Which cranial nerves transmit taste sensation...Ch. 15.3 - 7. Which part of the brain is responsible for...Ch. 15.4 - What are the functions of the tarsal glands and...Ch. 15.4 - Trace the path of tears as they travel from the...Ch. 15.4 - 3. Which two extrinsic eye muscles move the eye...Ch. 15.4 - Prob. 4QC Ch. 15.4 - 5. What are the functions of each component of...Ch. 15.4 - 6. What are the two fluids found in the eyeball?...Ch. 15.5 - Prob. 1QC Ch. 15.5 - Prob. 2QC Ch. 15.5 - What is accommodation?Ch. 15.5 - Prob. 4QC Ch. 15.5 - 5. What is the near point of accommodation, and...Ch. 15.5 - 6. How do myopia and hyperopia differ? Ch. 15.5 - How are rods different from cones?Ch. 15.5 - Why are photoreceptors depolarized in the dark?Ch. 15.5 - How do rods hyperpolarize when light strikes them?...Ch. 15.5 - 10. What happens at the optic chiasma? What is...Ch. 15.5 - 11. What type of visual processing occurs in the...Ch. 15.6 - 1. What is the auricle? Ch. 15.6 - What is the purpose of cerumen?Ch. 15.6 - 3. Where is the tympanic membrane located? Ch. 15.6 - Prob. 4QC Ch. 15.6 - What is the role of the pharyngotympanic tube?Ch. 15.6 - What are the functions of the utricle, saccule,...Ch. 15.6 - How are the scala tympani, scala media, and scala...Ch. 15.6 - 8. What is the spiral organ, and where is it...Ch. 15.7 - 1. What physical properties determine the pitch...Ch. 15.7 - 2. What is the range (in hertz) of human...Ch. 15.7 - 3. Why is the force exerted on the oval window...Ch. 15.7 - Prob. 4QC Ch. 15.7 - Prob. 5QC Ch. 15.7 - Prob. 6QC Ch. 15.7 - Prob. 7QC Ch. 15.7 - Prob. 8QC Ch. 15.8 - How do static and dynamic equilibrium differ?Ch. 15.8 - 2. What role do the utricle and saccule play in...Ch. 15.8 - What role do they play in dynamic equilibrium?Ch. 15.8 - Prob. 4QC Ch. 15.8 - 5. What are the three primary areas of the...Ch. 15 - Match the cell type with the correct stimulus....Ch. 15 - 2. The axons of the olfactory nerve terminate in...Ch. 15 - 3. Fill in the blanks: In an olfactory neuron, the...Ch. 15 - The primary olfactory cortex is located in the: a....Ch. 15 - 5. Which of the following statements is true...Ch. 15 - Match the taste with the chemical substance that...Ch. 15 - Prob. 7CYR Ch. 15 - Prob. 8CYR Ch. 15 - 9. Which cells in the retina are depolarized in...Ch. 15 - Prob. 10CYR Ch. 15 - Each of the following statements is false. Correct...Ch. 15 - The axons from the nasal retina in the left eye...Ch. 15 - Mark the following statements as true or false. If...Ch. 15 - Explain how sounds of different frequencies are...Ch. 15 - Prob. 15CYR Ch. 15 - Prob. 16CYR Ch. 15 - Prob. 17CYR Ch. 15 - 18. True or false: Hair cells in the spiral organ...Ch. 15 - 19. Which of the following is not part of the...Ch. 15 - 20. Fill in the blanks: In the ampulla of a...Ch. 15 - Stimuli from the inner ear regarding head movement...Ch. 15 - 1. Explain what would happen to your sense of...Ch. 15 - In which direction would you be unable to move...Ch. 15 - If a patient suffers visual impairment only in one...Ch. 15 - 4. Following a stroke, a patient lost vision in...Ch. 15 - Why do you have the sensation that you are still...Ch. 15 - 1. Mr. Spencer suffers loss of taste sensation....Ch. 15 - 2. Your friend tells you that she has just been...Ch. 15 - Prob. 3AYKA Ch. 15 - Prob. 4AYKA Ch. 15 - Mrs. Flores is a 45-year-old female who suffered a...Ch. 15 - 6. Your 60-year-old patient, Mr. Guster, has...

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