Hearing Flashcards
What’s the definition of sound?
Vibration with areas of compressions and rarefactions that moves through a medium. The amount of waves that pass from a certain point in a given time
What’s a wavelength?
Sound pressure
What can sound travel through?
Air, liquids, and solids
What are the 3 different frequencies of sound?
Infrasound (<20Hz), Audible frequencies (20Hz-20kHz), and Ultrasound (>20 kHz)
What animals can hear ultrasound? Infrasound?
Ultrasound- Bats, Dolphins, Mice, Rats, Some Frogs, Lots of, Insects, Dogs, Cats, and many fish
Infrasound- Elephants, Whales, Giraffes, Okapi, Rhinoceroses, Hippopotamuses, Lots of Frogs, Alligators, and Beavers
What are mechanoreceptors basic definition? Used in what?
- Respond to mechanical deformation caused by stimuli such as touch, pressure, stretch, motion, and sound
- Used in proprioception and hearing
- Turn stimulus into chemical signals
What are the 4 basic types of mechanoreceptors?
- Hair (humans)- Tubular body, Lymph space, epithelium and neuron
- Campaniform (Arthropods)
Cuticle, neuron, epithelium - Chordotonal (Insects and crutaceans)
Attatchment, cuticle, scolopale, and bipolar neuron - Silt (Arachnids)
Epithelium
Describe the hair mechanoreceptor.
- Good in air and fluid
- Deformation triggers ion influx and action potential
Describe the campaniform mechanoreceptor.
-Detect stress to cuticle
-Cuticular covering bulges out
-Many on body for proprioception
-On antennae for hearing
Insects
Describe the chordotonal mechanoreceptor.
- Stretch receptors
- Can respond to substrate and air vibrations picked up by tympanum (eardrum) or by moving of antenna (flies)
Describe the silt mechanoreceptor.
- Only in arachnids (spiders)
- Similar to insect campaniform sensilla
- Many on body for proproiception
- Cuticular covering bulges inward
What are statocysts?
- Statoliths – dense particles of calcium carbonate
- Their movement stimulates mechanoreceptors
- Detects gravity
- Found in cnidarians, ctenophores, echinoderms, crustaceans, bivalves and cephalopods
What is a hair cell? How are they used in signal transduction?
- Sensory receptors for hearing and equilibrium are hair cells
- Hair cell is slightly depolarized at rest
What are the 3 regions of the ear?
- The external ear – collect and channel sound waves
- The middle ear – bony system to amplify vibrations
- The internal ear- generate AP (action potential)
What is the external ear anatomy?
The auricle (pinna), a flap of elastic cartilage covered by skin and containing ceruminous glands