Flashcards in Chapter 2 Deck (47):
3 classes of fish
agnatha, chondrichyte, osteichthyes
most important evolution adaptations for fish?
jaws and paired fins
thin walled sac filled with gas that allows fish to float w/o effort
what type of digestive system do fish have?
what 3 functions do gills serve?
-exchange of gases
-removal of nitrogen waste
-osmoregulation of water/ion concentration remain balanced
describe respiratory system
Gills are used for breathing in fish. These are external organs that exchange gases in the water.
hard plate on both sides of head, protects and allows water to flow through the mouth to the gills
how do freshwater fish stay balanced?
how do saltwater fish keep balanced?
urinate less, drink sea water to replace lost water.
sensory structure detects changes in temp, pressure, current, and vibrations
describe their circulatory system
2 chambered heart, very simple.
structures containing pigments that provide color patterns, found in the skin layer.
fish are cold blooded. what does this mean?
ectothermic, really on external environment to adjust body temp
describe cycloid scales
describe ganoid scales
thick bony, don't form rings
describe ctenoid scales
eggs stay inside mouth until they hatch
give birth to live young
external fertilization of eggs
breathe thru gills
no paired fins
no lateral line
no swim bladder
7 gill slits
rows of teeth
what 3 types of fish belong to chondrichthyes? what type of scales would you find on them
sharks rayes and skates.
placoid scales- tooth like dermal spines on scales
ray finned fish characteristics
4 gills covered by operculum
where would you find the dorsal fin? what is its job?
top of fish, keeps fish upright.
where would you find the caudal fin? what is its job?
posterior end of fish, allows fish to move forward
where would you find the pectoral fins and pelvic fins? what do they do?
pectoral- sides of fish most anterior
pelvic- sides of fish most posterior
help steer, brake, move up and down, and orient body at rest.
fish that migrate between freshwater and saltwater habitats
collection of fish that have gathered togethor
group of fish that stay togethor for social reasons, independent, fish of diff species and sizes
group swimming in same direction in a coordinated manner. same color and size
what are the differences between schooling and schoaling?
schooling- all the same size and color going in the same coordinated direction
schoaling- different sizes and colors, swimming independently in same gen area
branch of zoology that studies fish
someone that raises domesticated fish for human consumption/use
describe freshwater habitats
40% of all fish are found in freshwater. springs, pounds, rivers, lakes, etc.
describe saltwater habitats
covers 71% of earth surface, includes oceans and estuaries
what is a dog shark's scientific name?
why are dog sharks also known as spiny dogfish?
they have 2 spines
how do dog sharks reproduce?
how long do dog shark females stay pregnant?
why are dogfish called dogfish?
they travel and hunt in packs like doga
how do dogfish defend themselves?
they use their back spines. curling around in a bow and striking
what would happen if freshwater fish didnt keep balanced in water?
their cells would pop and they'd die.
what would happen if saltwater fish didn't keep balanced in water?
they'd dehydrate and die.
what is an example of why lacking a swim bladder would be an advantage?
for example, in sharks not having a swim bladder is an advantage because it allows them to move between different depths without the risk of exploding or imploding.