Lecture 13

Question 1

major fish groups

Answer 1

jawless fish (agnatha)

cartilaginous fish

bony fish

Question 2

why aren’t fishes a natural taxonomic group

Answer 2

doesn’t include humans (vertebrates)

Question 3

describe features of fish that are adaptive to aquatic environnments

Answer 3

swim bladders
- physoclistous condition
- physostomous (connected)

paired fins

operculum
- hard protective structure over gills

slime as lubricant

Question 4

describe the lateral line system

Answer 4

used to detect low fequency vibration in surrounding water

present in fishes and some larval amphibians

external openening to the later line canal between scales

neuromast (sensory cells along the lateral canal

cupula gets displaced by vibrations wich moves the sense hairs and activate the sensory cells sending signals along the nerve