Without water, there is no life. This is a fact that cannot be released from all living things on earth. For animals, drought can have damaging effects that lead to mass extinction and a lack of population. Water is taken and drink by mouth, a simple method that is natural to us. But what about the animals that are in the water? do fish drink water – in what ways do fish drink?
Do fish drink water?
Before discussing how freshwater fish drink, we should learn a little chemistry related to the way water flows. In addition to flowing from top to bottom due to gravitational forces, water also flows from high concentrations to low concentrations.
An example of this phenomenon is the transfer of water from the salty part to the fresh part. Water transfer due to this difference in concentration is called diffusion.
Well, the body of freshwater fish itself has a higher concentration aka saltier than the water in its environment. As a result, fresh fish does not need to drink and just wait for the water to enter their body through gills or a thin layer of skin.
To avoid obesity due to drinking mostly water when eating, fresh fish very often pee. Meanwhile, fresh fish skin also has a layer of chloride cells. Because it is salty, this cell also regulates the amount of water to fit the needs and avoids the body mostly absorbing water.
In contrast to freshwater fish, fish that live in saltwater has a lower concentration of water in the body than the environment, namely the sea. As a result, the water in the fish’s body is sucked out.
In order not to dehydrate, sea fish are very diligent in drinking and large quantities. If you don’t do that, of course, the fish will run out of fluids. But isn’t the water in the sea also salty?
Well, to overcome that, fish have kidneys and gills that can filter sea salt so that it can be sucked safely by the body. Besides, the layer of chloride cells in the body of the fish serves to pump out excessive salt in the body of the fish. In essence, either the body of freshwater fish or saltwater are both looking for a balance of water concentration in the body to be able to live.
Sharks may be classified as saltwater fish, but the body of the shark turns out to be as salty as the seawater itself. This can happen because sharks actively remove body salts in the form of urea substances from their skin.
Besides, sharks do not need to drink. They prefer to absorb water directly through the gills before finally being filtered. So, it can be said that sharks as saltwater fish behave like freshwater fish.
Some types of sharks can even easily swim from the sea to around the downstream rivers that have fresh water. This may happen because sharks can regulate how much their pee is through ‘peeing’ urea.
Do Fish also Sleep?
If a living creature sleeps by covering its eyelids and lying down, this is not the case with fish. First, they don’t have eyelids. Secondly, sharks are the only marine mammals that have eyelids and they close them only when protecting their eyes. Another reason, fish should continue to swim because they need constant gill ventilation.
Research shows that fish can reduce their activity and metabolism while staying alert to dangers. The way the fish rests is different, depending on the species.
Some fish float on the spot, some cramm themselves in a safe place in mud or coral, and some rest in comfortable nests. Whatever state of rest they do, this is the period when activity and metabolism slow down as a way to conserve and restore energy.
It is the same as the function of sleep in humans. Anyway, research has also demonstrated that the period of time bass sleep is dependent upon the species, how busy the fish is, along with other environmental aspects.
For fish that live in the aquarium, its sleep cycle is determined by interior lights. Fish in the aquarium will sleep when the lights are turned off. Many fish, such as small fish and coral reef fish, are active during the day and sleep at night. But some do the opposite, namely more active at night.
Another interesting fact, fish can suffer from sleep disorders or sleep deprivation like humans. For example, zebrafish, which naturally drop their tail and stay at the bottom of the tank or just below the surface of the water to sleep.
Zebrafish that lack something called hypocretin receptors show classic signs of insomnia (having trouble sleeping and possibly not being able to sleep) during the disorder. If the sleep disorder is gone, the fish can rest longer than usual.
Here are 5 types of sea fish that can be consumed, healthy, and easy to process have been:
The first type of sea fish that can be consumed is snapper. There are two types of snapper, namely red snapper and barramundi.
red snapper because of its thicker meat than barramundi.
The content in a snapper is also good for health. This type of sea fish that likes to live on the coral reefs, contains a lot of nutrients and high selenium content that is good as an antioxidant for the body. Besides, snapper also contains vitamin E which is good for maintaining skin health.
Cob fish is widely processed into delicious food. Cob fish is still a family with tuna.
This type of sea fish has a lot of nutrients, one of which is iron. Iron is very beneficial for your body in the formation of red blood cells.
This type of sea fish has soft and thick meat. No wonder tuna fish are much loved by the public for consumption. In addition to its soft and tasty meat, tuna fish is also famous for being rich in proteins that are good for maintaining body tissues and containing low fat so it is safe to consume and good for heart health.
This delicious and luxurious dish is Ahi Tuna Recipes Pan-Seared Without Soy Sauce, fresh tuna cooked with a sprinkling of sesame will give off a distinctive aroma served with a healthy and very delicious seaweed rujak. You’ll get it in less than 30 minutes.
Are you one of those people who often eat sardines? Sardines themselves belong to a type of sea fish that has a small body size.
Sardines come from the Mediterranean region which is found a lot of this type of sardines. This type of sea fish even has 21 species according to who and FAO.
The Heart Foundation in the United States recommends consuming mackerel to reduce the risk of heart disease. However, one type of mackerel known as King mackerel (Scomberomorus cavalla) contains high levels of mercury and should not be consumed by pregnant women, nursing mothers, or toddlers.
Atlantic mackerel and Pacific mackerel are known to contain low mercury and per 4 ounces contain up to 2,100 milligrams of EPA and DHA. So it is better when you want to eat mackerel you should pay attention to it carefully.