3 - Fishes 2

Question 1

Bony fish

Answer 1

some bone in skeleton or scales
bony operculum covering gill openings
lungs or swimbladder
very successful group (50% of vertebrates and 95% of fish)

Question 2

1st fossils of bony fish

Answer 2

405 mya, silurian period

Question 3

Radiation of both classes

Answer 3

Devonian period 350 mya

Question 4

Class sarcopterygii

Answer 4

• led to tetrapods
• lobe-finned fishes
• lungfish
• coelacanths
• tetrapodomorpha

Question 5

tetrapodomorpha

Answer 5

extinct ancestors of tetrapods

Question 6

Lungfish

Answer 6

some burrow in mud when rivers or lakes dry up
keep narrow pathway open for air
aestivation = up to 6 months

Question 7

coelacanth

Answer 7

most recent fossils 70mya

thought to be extinct till 1938

Question 8

class actinopterygii

Answer 8

large group
ray finned fishes, lack muscular lobes
Have swim-bladders

Question 9

Chondrosteans

Answer 9

“ray-finned”
Ancient members had bony skeletons
Living members have cartilaginous skeletons

Question 10

Lake sturgeon

Answer 10

used to be lots but harvested and dams messed u their habitat and separated them from mating areas
rebound due to us cleaning lakes and stopping fishing them
takes a long time to recover since they don’t mate often

Question 11

Neopterygii

Answer 11

largest group of ray finned fishes

Question 12

Neopterygii 2 genera

Answer 12

Amia (bowfin)

Lepisosteus (garpike)

Question 13

Amia

Answer 13

gulp air for oxygen

Question 14

lepisosteus

Answer 14

air breathing

Question 15

Modern bony fish

Answer 15

Teleosts

Question 16

parental care in small mouth bass and fishing

Answer 16

need to stage before spawning and their bowl nests are easy to see. they’re also very aggressive, making them easy to fish. reproduction takes a long time

Question 17

Very poisonous fish

Answer 17

Pufferfish

Question 18

Problems with movement in water

Answer 18

Denser than air, but less gravity

Question 19

Fish design due to moving in water

Answer 19

• Streamlined
• Mucoid secretions
• Arrangement of body-wall muscles
• fin shape

Question 20

Feeding strategies

Answer 20

Herbivores, omnivores, some filter feeders

Question 21

Most teleosts feed how?

Answer 21

Predators/carnivores that swallow food whole

Question 22

Circulation in regular fish

Answer 22

• Closed system
• 4 part heart
• single circuit
• high metabolic rate

Question 23

Lungfish circulation

Answer 23

partially divided by septum
pulmonary and systemic circuits
was precursor to 4 chambered heart

Question 24

Gas exchange

Answer 24

• tidal ventilation (like us) is not energetically efficient in water cause of density
• Water moves in 1 direction over gills
• Countercurrent exchange mechanism maximizes gas transfer (blood and water in opposite directions) in pharyngeal lamellae

Question 25

Tuna and other fish gas exchange

Answer 25

No blub blub, swim with with mouths open, continuously move water across gills Ram ventilation

Question 26

Swim bladders

Answer 26

Pneumatic sacs connect to digestive tract in nonteleost fish Function as lungs in lungfish Function as swimbladders in other bony fish Adjusts buoyancy

Question 27

Buoyancy

Answer 27

- low density compounds - fins provide vertical lift - reduction of heavy tissues like bone - swim bladders (except sharks which use lipids)

Question 28

Vision

Answer 28

Lidless eyes | Predatory teleosts rely heavily on vision to find food (big part of brain)

Question 29

Smell

Answer 29

External nares lead to field receptors in olfactory sacs | Olfactory epilthelium

Question 30

Catfish tasting

Answer 30

chemoreceptors all over body so very good at tasting

Question 31

Salmon and olfaction

Answer 31

use it for their last part of their migration. also have magnetite to help with the "compass" part of their migration

Question 32

Olfaction and pollution

Answer 32

mess up smells and so can ruin migrations for migratory species

Question 33

Taste in fish

Answer 33

chemoreceptors for taste in mouth and also on head and body

Question 34

Hearing

Answer 34

- no external ears (ear bones inside, sound travels through tissue of skull) - hear really well - sound travels better in water than air

Question 35

Hearing and sound pollution

Answer 35

Water bodies that are too loud due to boats and things can confuse fish

Question 36

Lateral line system

Answer 36

- receptors that detect water currents (water movements caused by predators or prey) - canals with sensory hairs - warning system

Question 37

Electroreception

Answer 37

sense and stun prey and objects around them

Question 38

Electric eels

Answer 38

can deliver an electric charge of up to 500 volts, to stun prey or deter predators