Answer:
The answer is water
Explanation:
Hydro means water. So the hydro sphere can be affected by water pollution from human wastes.
Adaptations increase the probability of an organism surviving and reproducing in a specific environment.
Answer:
Where does the dna in our cells come from? it comes through inheritance from parents
Explanation:
Every living organism has its genetic make-up which is located in the DNA and resides in the nucleus of a cell. DNA is unique to an individual without having a similar or carbon copy, it is inherited from the parents.
This is called the metabolism. Hope this helps.
The 3 groups of fish are:
Jawless, cartilaginous and bony fishes.
Jawless fish were one of the first vertebrates in this world. These fish have no scales, and instead are made of cartilage. Also, like the name says, they have no jaws and no fins. Some jawless fish include hagfishes and lamprey's. These are the only species alive today.
Cartilaginous fish include sharks and rays. Their skeletons are made out of cartilage, similar to the jawless fish. But, they do have jaws and fins. Their bodies are covered with pointy teeth-like scales, which makes their skin rougher than sandpaper.
Bony fish have scales that overlap each other, and instead of cartilage, they have bones like other animals. These scales are made from the same substance as your fingernail. The slimy substance mucus covers the fish (it's in your throat and nose as well), and protects it from other dangerous things. Bony fish are basically 95% of all fish.