Load your fish­ing gear and head to KZN

Pitch camp at the Tugela Mouth Re­sort, and hook an elf, grunter or big­eye stump­nose.

Go! Camp & Drive - - Reel & Wheel - Sources macmil­lan­learn­ing.com, in­di­ana­pub­lic­me­dia.org and amnh.org

How do fish drink? Be­cause fish live in the water, most peo­ple think they also drink that water. But you’ll be sur­prised: It’s true in some cases, but def­i­nitely not in all. Peo­ple drink fresh water, but you can die of thirst next to the sea be­cause the salt in the water will de­hy­drate you. It works a bit dif­fer­ently with fish: Fish in the sea drink the water, but fish in fresh water do not. Fresh­wa­ter fish take water in through their mouth and it runs out through their gills. The water is ab­sorbed into the fish’s blood­stream via the gills through a process called os­mo­sis. That’s be­cause the fresh water con­tains a lower con­cen­tra­tion of dis­solv­able sub­stances (like salts and sug­ars) than in the fish’s body. There­fore fresh­wa­ter fish don’t phys­i­cally drink the water they take in. In the case of sea fish, the con­cen­tra­tion of salt dis­solved in the water is higher than that in the fish’s body. Some of the water the fish takes in through its mouth also moves over the gills, but it swal­lows the rest of the water, which then lands in its di­ges­tive sys­tem. Here the water is ab­sorbed into the blood­stream – just like with peo­ple. So sea fish drink their water. The dif­fer­ences be­tween th­ese two types of fish are even more ap­par­ent if you look at their ex­cre­tion. A fresh­wa­ter fish re­leases a large amount of urine be­cause of all the water that’s ab­sorbed into the blood­stream. With sea fish it works the other way round, be­cause this type of fish re­leases water out of the blood­stream via the gills through dif­fu­sion. That means sea fish re­lease less urine, but it’s a lot more con­cen­trated with loads of waste prod­ucts and ab­sorbed salts.

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