USING RADIOISOTOPES IN FISHERY RESEARCH 



MOVEMENT OF TRACE METALS f 



I Di»1Mb«l.o" 1l\th tlm« *tl«r l««li« O* lt*«lo(»«lop«* 



TRACE METAL METABOLISM 



UPTAKE -ACCUMULATION 

 ABSORPTtON - rON TRANSPORT 



1 STUDYING THE PHYSIOLOGY OF FISH 



ION PROTEIN tNTERACTIONS 

 METAH-O- ENZYMES 

 EXCRETION 



DETERMINING FILTERING RATES OF CLAMS 



CYCLING OF ELEMENTS 



MEASURING PRIMARY PRODUCTIVITY 



Figure 13.— New research possibilities have arisen In the field of ecology as radioactive tracers nave become available. 

 The movement of trace elements through experimental ponds Is followed by using radioactive isotopes of the elements 

 as tags or labels. The capacity of clams to filter food from water Is measured through the use of algae labeled with 

 radioactive elements. Also, the rate at which carbon is produced by plants— primary production— can be determined by 

 rate of uptake of carbon 14 by the plants. 



13 



