Osmoregulation
70.3 هزار بار بازدید -
7 سال پیش
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This video shows how organisms
This video shows how organisms regulate the amount of water they keep in their systems.
** If there are any pictures used in this video, they are NOT MINE and I will not take credit for them. **
TRANSCRIPT:
Osmoregulation describes the regulation of water and salt concentrations for an organism. Animals must balance the amount of water that they keep and the amount of water that they excrete. This is a difficult task because we excrete nitrogenous wastes through urine, and water must be used in order to dilute the nitrogenous wastes. The breakdown of proteins and nucleic acids from food results in these wastes, such as ammonia, urea, and uric acid. Ammonia is the most toxic form, while uric acid is the least toxic. Because ammonia is very toxic, it requires a lot of water to be excreted along with it.
Solutions can also differ in what we call osmolarity. Osmolarity is a measure of how concentrated a solution is. There are three words that we can use to describe osmolarity: hypertonic, hypotonic, and isotonic. A solution is hypertonic to another if that solution has a higher solute concentration. That means that this other solution is hypotonic to the one we just talked about, because it has a lower solute concentration. Furthermore, if the two solutions had the same amount of solutes, then we would say that they are isotonic to one another.
There are two types of animals when it comes to osmoregulation: osmoregulators and osmoconformers. Osmoregulators need to use up energy to control their internal solute concentrations, while osmoconformers are isoosmotic with the environment.
When we examine the nitrogenous wastes of an organism, it can help us predict the habitat it’s living in. This freshwater fish can excrete ammonia, the most toxic form of nitrogenous waste. That’s because it’s surrounded in fresh water, and there’s not much salt in its environment. Therefore, ammonia is the best option because it has plenty of water to excrete along with it. We can also say that the freshwater fish’s cells are hypertonic to the surrounding water, because the fish has a higher solute concentration inside its body than outside in the water. In contrast, marine bony fish are surrounded by saltwater, which has a very high solute concentration. That means the bony fish’s cells are hypotonic to the surrounding water, and marine bony fish must excrete small amounts of concentrated urine in order to keep getting rid of the salt coming in. Also, marine bony fishes excrete urea.
Us humans excrete urea, too, which is less toxic than ammonia. But, there’s also a downfall to excreting something less toxic – it takes work and time to convert ammonia into urea. Therefore, it requires more energy and more food. But it’s not like we’re surrounded by water every minute of our lives like the freshwater fish. We don’t have enough water to be able to excrete ammonia safely, so instead, our bodies have adapted to excreting urea.
The last nitrogenous waste that I’ll talk about today is called uric acid, and it is less toxic than urea. But, of course, it takes a considerable amount of energy to produce it, even though very little water is needed to excrete it. Some animals that excrete uric acid are birds and reptiles.
** If there are any pictures used in this video, they are NOT MINE and I will not take credit for them. **
TRANSCRIPT:
Osmoregulation describes the regulation of water and salt concentrations for an organism. Animals must balance the amount of water that they keep and the amount of water that they excrete. This is a difficult task because we excrete nitrogenous wastes through urine, and water must be used in order to dilute the nitrogenous wastes. The breakdown of proteins and nucleic acids from food results in these wastes, such as ammonia, urea, and uric acid. Ammonia is the most toxic form, while uric acid is the least toxic. Because ammonia is very toxic, it requires a lot of water to be excreted along with it.
Solutions can also differ in what we call osmolarity. Osmolarity is a measure of how concentrated a solution is. There are three words that we can use to describe osmolarity: hypertonic, hypotonic, and isotonic. A solution is hypertonic to another if that solution has a higher solute concentration. That means that this other solution is hypotonic to the one we just talked about, because it has a lower solute concentration. Furthermore, if the two solutions had the same amount of solutes, then we would say that they are isotonic to one another.
There are two types of animals when it comes to osmoregulation: osmoregulators and osmoconformers. Osmoregulators need to use up energy to control their internal solute concentrations, while osmoconformers are isoosmotic with the environment.
When we examine the nitrogenous wastes of an organism, it can help us predict the habitat it’s living in. This freshwater fish can excrete ammonia, the most toxic form of nitrogenous waste. That’s because it’s surrounded in fresh water, and there’s not much salt in its environment. Therefore, ammonia is the best option because it has plenty of water to excrete along with it. We can also say that the freshwater fish’s cells are hypertonic to the surrounding water, because the fish has a higher solute concentration inside its body than outside in the water. In contrast, marine bony fish are surrounded by saltwater, which has a very high solute concentration. That means the bony fish’s cells are hypotonic to the surrounding water, and marine bony fish must excrete small amounts of concentrated urine in order to keep getting rid of the salt coming in. Also, marine bony fishes excrete urea.
Us humans excrete urea, too, which is less toxic than ammonia. But, there’s also a downfall to excreting something less toxic – it takes work and time to convert ammonia into urea. Therefore, it requires more energy and more food. But it’s not like we’re surrounded by water every minute of our lives like the freshwater fish. We don’t have enough water to be able to excrete ammonia safely, so instead, our bodies have adapted to excreting urea.
The last nitrogenous waste that I’ll talk about today is called uric acid, and it is less toxic than urea. But, of course, it takes a considerable amount of energy to produce it, even though very little water is needed to excrete it. Some animals that excrete uric acid are birds and reptiles.
7 سال پیش
در تاریخ 1396/02/15 منتشر شده
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