L 20 Flashcards
What is chemoreception?
The physiological response of a sense organ to a chemical stimulus.
What are two basic types of chemoreception?
- gustation
2. olfaction
how does olfaction result from?
stimulation of sensory receptor cells in the olfactory organs
How is gustation mediated?
by taste buds, and innervated by facial, glossopharyngeal and vagus nerves.
Taste buds are found in the wonder cavity and gill cavity
What may be a third type of chemoreception?
It is mediated by sensory receptors located on exposed body surfaces of a fish. Better developed in scaleless bottom living forms.
how are the olfactory organs structured on a fish?
nearly all fishes are paired bilateral structures that consist of olfactory chambers lined with various olfactory epithelia called lamelle
In general greater lamellae is associated with what?
associated with greater olfactory requirements and sensitivity odors
electroencephalograms
recording of electrical activity along the scalp
Where may gustation be important to fishes?
primarily in location and identification of possible food sources.
i.e minnows are sensitive to sugars and salts
How does the brain interpret sound?
the bending of fine, hair like structure of the sensory cells, which in turn produce nervous/electric signals
What occurs if the swimbladder of clupeomorphs and ostariophysans are damaged?
It reduces their sound detecting abilities since the swimbladder is mechanically connected to the inner ear by a series of bony ossicles.
What does the lateral line system consist of?
several series of sensory structures called neuromasts runing over the head and body.
- inner ear
- lateral line system
What are neuromasts?
sensory structures that encapsulate hair cells that produce nervous impulses when bent in one direction.
What is the lateral line system?
a system of tactile sense organs, unique to aquatic vertebrates to amphibians, that serves to detect movements and pressure changes in the surrounding water.
What is the endolymphic fluid?
Free neuromasts that lie on the skin has a series of receptors that is filled with this fluid, and it picks up and passes vibration to the neuromasts through a series of opening through the scales of the fish
What is the cupula?
a rounded gelatinous cupula rests on top of a sensory structure and moves when it senses a disturbance
How may the position and distribution of the lateral line relate to the ecology of the species?
If the fish feeds on the surface, then the lateral lines run along the ventral marin of the body.
if it’s a bottom living fish, then the lateral line is elevated on the body to warn of predators approaching from above.
What kind of function does the lateral line receptors serve that is independent of hearing? (3)
- predator avoidance
- schooling behavior
- obstacle avoidance
- feeding behavior
the fish creates a bow wave in front of it as it swims and pressure changes associated with this bow wave hitting oncoming objects informs the fish of their approach
Why may the blind cave fish, popular in aqaurium trade, not run into the glass?
due to the lateral line system
