FISHES

Výukový materiál OR 03 - 73Tvůrce: Mgr. Alena Výborná

Tvůrce anglické verze: ThMgr. Ing. Jiří FollerProjekt: S anglickým jazykem do dalších předmětů

Registrační číslo: CZ.1.07/1.1.36/03.0005Tento projekt je spolufinancován ESF a SR ČR

FISHES● the most numerous class of vertebrates

● the oldest proofs of their existence are known

from Paleozoic – 440 million years ago

● in all types of water

● various body shapes

● skeletons have different mass of ossification

FISHES

● gas bladder – filled with gases with

overwhelming nitrogen, it unweights the fish body

and helps keep it in a particular position and in

various depths

● stream organ – noticeable as the lateral line,

orientation in the environment

● there are over 25 000 fish species in the world

FISHES● gill is protected from the outside

● the body is usually provided with a symmetrical

caudal fin, pair fins pectoral and pelvis and non-pair

dorsal and anal fins

● fins are stiffened with osseous fin races

● some species have a apidose fin (salmon)

FISHES

● fresh water fishes:

● all fishes living in our country are usually located in

four basic types of flowing water – fish zones

● 1) trout zone : upper fast flowing section

(mountain streams)

● 2) grayling zone: streams and rivers on foothills

FISHES

● 3) barbel zone: middle section of rivers with

broad river-basins and fast streaming water

● 4) bream zone: lowlands, slowly flowing water

with dead-end branches

● this natural division can be disturbed by the

human activity

FISHES

•prevailing fishes in our fauna are carp fishes•common carp:•originally wild• it lived in rivers•domesticated - fishponds

CARP

FISHES

•crucial carp:•similar to common carp• it has not got whiskers around the mouth•polluted water does not bother it•common tench:• tiny scales, deep under the skin•stagnant water

CRUCIAL CARP

COMMON TENCH

FISHES

•common roach:• red eyes• the most common carp fish

COMMON ROACH

FISHES

•other members of our fauna:• river bass:•nice colourful fish• in all types of water•common zander:•delicious low-fat meat

RIVER BASS

FISHES

•common trout:•salmonoid fish• fast flowing water rich in oxygen•mountain, foothill areas•common pike:•sport fish•slowly flowing, stagnant water

COMMON TROUT

COMMON PIKE

FISHES

•big catfish:•our biggest fish•slowly flowing, stagnant water• river eel:•serpentiform body•on the bottom•active at night

BIG CATFISH

EEL

FISHES

•COMMERCIAL IMPORTANCE OF FISH:• food for humans• fish meat covers 15 % of food of animal origin• freshwater fishing in the Czech republic focuses

mainly on fish farming in fishponds•sea fish are an important part of national

economics for sea countries (herring, cod, mackerel, tuna…)

Review:

•1) What are the main features of fish?

•2) When did the first fishes appear?

•3) Gas bladder is used for…………..

•4) How can fish orient in the environment?

•5) Can a trout be caught in the pond?

•6) Which is our most common fish?

Source:• DOBRORUKA, Luděk J. Přírodopis pro 7. ročník základní

školy. 1. vyd. Praha: Scientia, 1998, 152 s. ISBN 80-718-3134-4

• Obrázky: http://commons.wikimedia.org (osvobozeno od autorských práv)