
Concept explainers
Occupational Hearing Loss Frequent exposure to loud noise of a particular pitch can cause loss of hair cells in the part of the cochlea that responds to that pitch. People who work with or around noisy machinery are at risk for such frequency-specific hearing loss. Taking precautions such as using ear plugs to reduce sound exposure is important. Noise-induced hearing loss can be prevented, but once it occurs it is irreversible because dead or damaged hair cells are not replaced.
FIGURE 33.11 shows the threshold decibel levels at which sounds of different frequencies can be detected by an average 25-year-old carpenter, a 50-year-old carpenter, and a 50-year-old who has not been exposed to on-the-job noise. Sound frequencies are given in hertz (cycles per second). The more cycles per second, the higher the pitch.
FIGURE 33.11 Effects of age and occupational noise exposure on hearing. The graph shows the threshold hearing capacities (in decibels) for sounds of different frequencies (given in hertz) in a 25-year-old carpenter (blue), a 50-year-old carpenter (red), and a 50-year-old who did not have any on-the-job noise exposure (brown).
How loud did a 1,000-hertz sound have to be for the 50-year-old carpenter to detect it?

Want to see the full answer?
Check out a sample textbook solution
Chapter 33 Solutions
Biology: The Unity and Diversity of Life (MindTap Course List)
- How many milligrams of zinc did you consume on average per day over the 3 days? (See the Actual Intakes vs. Recommended Intakes Report with all days checked.) Enter the number of milligrams of zinc rounded to the first decimal place in the box below. ______ mg ?arrow_forwardthe direct output from molecular replacement is a coordinate file showing the orientation of the unknown target protein in the unit cell. true or false?arrow_forwardthe direct output from molecular replacement is a coordinate file showing the orientation of the unknown target protein in the unit cell. true or false?arrow_forward
- Did your intake of vitamin C meet or come very close to the recommended amount? yes noarrow_forwardWhich of the following statements about hydration is true? Absence of thirst is a reliable indication that an individual is adequately hydrated. All of these statements are true. Although a popular way to monitor hydration status, weighing yourself before and after intensive physical activity is not a reliable method to monitor hydration. Urine that is the color of apple juice indicates dehydration. I don't know yetarrow_forwardThree of the many recessive mutations in Drosophila melanogaster that affect body color, wing shape, or bristle morphology are black (b) body versus grey in wild type, dumpy (dp), obliquely truncated wings versus long wings in the male, and hooked (hk) bristles versus not hooked in the wild type. From a cross of a dumpy female with a black and hooked male, all of the F1 were wild type for all three of the characters. The testcross of an F1 female with a dumpy, black, hooked male gave the following results: Trait Number of individuals Wild type 169 Black 19 Black, hooked 301 Dumpy, hooked 21 Hooked, dumpy, black 172 Dumpy, black 6 Dumpy 305 Hooked 8 Determine the order of the genes and the mapping distance between genes. Determine the coefficient of confidence for the portion of the chromosome involved in the cross. How much interference takes place in the cross?arrow_forward
- What happens to a microbes membrane at colder temperature?arrow_forwardGenes at loci f, m, and w are linked, but their order is unknown. The F1 heterozygotes from a cross of FFMMWW x ffmmww are test crossed. The most frequent phenotypes in the test cross progeny will be FMW and fmw regardless of what the gene order turns out to be. What classes of testcross progeny (phenotypes) would be least frequent if locus m is in the middle? What classes would be least frequent if locus f is in the middle? What classes would be least frequent if locus w is in the middle?arrow_forward1. In the following illustration of a phospholipid... (Chemistry Primer and Video 2-2, 2-3 and 2-5) a. Label which chains contain saturated fatty acids and non-saturated fatty acids. b. Label all the areas where the following bonds could form with other molecules which are not shown. i. Hydrogen bonds ii. Ionic Bonds iii. Hydrophobic Interactions 12-6 HICIH HICIH HICHH HICHH HICIH OHHHHHHHHHHHHHHHHH C-C-C-C-C-c-c-c-c-c-c-c-c-c-c-c-C-C-H HH H H H H H H H H H H H H H H H H H HO H-C-O H-C-O- O O-P-O-C-H H T HICIH HICIH HICIH HICIH HHHHHHH HICIH HICIH HICIH 0=C HIC -C-C-C-C-C-C-C-C-CC-C-C-C-C-C-C-C-C-H HHHHHHHHH IIIIIIII HHHHHHHH (e-osbiv)arrow_forward
- Biology: The Unity and Diversity of Life (MindTap...BiologyISBN:9781305073951Author:Cecie Starr, Ralph Taggart, Christine Evers, Lisa StarrPublisher:Cengage LearningBiology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxHuman Physiology: From Cells to Systems (MindTap ...BiologyISBN:9781285866932Author:Lauralee SherwoodPublisher:Cengage Learning
- Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage LearningPrinciples Of Radiographic Imaging: An Art And A ...Health & NutritionISBN:9781337711067Author:Richard R. Carlton, Arlene M. Adler, Vesna BalacPublisher:Cengage LearningHuman Biology (MindTap Course List)BiologyISBN:9781305112100Author:Cecie Starr, Beverly McMillanPublisher:Cengage Learning





