Lecture 17: Fish Flashcards
1
Q
pharyngeal slits
A
- located on lateral surface of head
- lost in echinoderms
- supported by arches
- becomes ear bones, jaw bones etc
2
Q
Function of pharyngeal slits
A
- filter feed
- evolved to help with respiration in vertebrates
- O2 and CO2 can be exchanged across respiratory surface
3
Q
bars between slits
A
gill arches
- made of bone or cartilage
- have gill filaments on them
4
Q
how many pairs of gill arches do bony fish have?
A
4
5
Q
feature that bony fish have
A
operculum (covers/protects gills)
6
Q
gill filament structure
A
thin, vascularized, high SA
- blood vessels flow through gill arches
- capillary beds in gill filaments; used for gas exchange
- water and blood flow in opposite directions
7
Q
Countercurrent exchange
A
- water and blood flow in opposite directions
- ensures concentration gradients are maintained
- achieves max gas exchange
8
Q
Fish Circulatory system
A
- system is closed
- arteries carry blood away from heart
- veins bring blood into hear
- 2 chambers
- ventrally located
- single circuit
9
Q
Vertebrate characteristics
A
- have axial skeletons (brain, spinal chord, ribs)
- appendicular skeleton
- closed circulatory system
- organs suspended in coelom
10
Q
Agnanthans
A
Jawless fish
- notocord present
- no paired fins
- no scaled
11
Q
Hag fish
A
MUCUSSS!!!!
- produce mucus as protection
- knot tying
12
Q
Lamprey
A
- have oral disc instead of jaws
- larval form found in mud
- as an adult: parasitic on fishes
- suck juices out of fish
13
Q
Jaws
A
- formed of fusion of gill arches
- teeth evolved from scales in mouth
14
Q
Paired fins
A
- on pectoral and pelvic limb girdles
- enables more active swimming
- used for steering and stabilizing
15
Q
Gnathostomes: cartilaginous fish
A
- have jaws, paired fins, scales, 5-7 gill arches
- no swim bladders
ex. sharks
