Ammonia is highly water-soluble and can be toxic to cells at low concentrations due to presence of its ammonium ion, which can interfere with oxidative phosphorylation. Ammonia is small and can easily diffuse through cell membranes, making it easy to excrete. Essentially, there is a trade off of easy excretion and toxicity levels.

For aquatic animals, however, toxicity is negligible due to the large volume of water available to dilute ammonia wastes. The high solubility of ammonia wastes and the abundance of water solvent allow for the ammonia to be transported out of cells in an very dilute concentration, without harming the organism. This allows aquatic organisms to conserve energy, compared to terrestrial organisms that must convert ammonia wastes to other forms.

Amphibians and mammals convert ammonia to urea, which can be excreted with less water, but must still be relatively dilute. These animals release liquid wastes from the body, resulting in water loss, but conserve energy compared to organisms that continue to convert urea into uric acid. Birds and reptiles excrete uric acid, which requires very little water waste, but uses a larger amount of energy in conversion. This is beneficial to animals that may not have ready access to fresh water.

Ammonia is highly water-soluble and can be toxic to cells at low concentrations due to presence of its ammonium ion, which can interfere with oxidative phosphorylation. Ammonia is small and can easily diffuse through cell membranes, making it easy to excrete. Essentially, there is a trade off of easy excretion and toxicity levels.

For aquatic animals, however, toxicity is negligible due to the large volume of water available to dilute ammonia wastes. The high solubility of ammonia wastes and the abundance of water solvent allow for the ammonia to be transported out of cells in an very dilute concentration, without harming the organism. This allows aquatic organisms to conserve energy, compared to terrestrial organisms that must convert ammonia wastes to other forms.

Amphibians and mammals convert ammonia to urea, which can be excreted with less water, but must still be relatively dilute. These animals release liquid wastes from the body, resulting in water loss, but conserve energy compared to organisms that continue to convert urea into uric acid. Birds and reptiles excrete uric acid, which requires very little water waste, but uses a larger amount of energy in conversion. This is beneficial to animals that may not have ready access to fresh water.

Ammonia is highly water-soluble and can be toxic to cells at low concentrations due to presence of its ammonium ion, which can interfere with oxidative phosphorylation. Ammonia is small and can easily diffuse through cell membranes, making it easy to excrete. Essentially, there is a trade off of easy excretion and toxicity levels.

For aquatic animals, however, toxicity is negligible due to the large volume of water available to dilute ammonia wastes. The high solubility of ammonia wastes and the abundance of water solvent allow for the ammonia to be transported out of cells in an very dilute concentration, without harming the organism. This allows aquatic organisms to conserve energy, compared to terrestrial organisms that must convert ammonia wastes to other forms.

Amphibians and mammals convert ammonia to urea, which can be excreted with less water, but must still be relatively dilute. These animals release liquid wastes from the body, resulting in water loss, but conserve energy compared to organisms that continue to convert urea into uric acid. Birds and reptiles excrete uric acid, which requires very little water waste, but uses a larger amount of energy in conversion. This is beneficial to animals that may not have ready access to fresh water.

Alcohol decreases the activity of antidiuretic hormone (vasopressin). A diuretic increases the production of urine and thus, inhibition of this _anti_diuretic hormone results in an increase in the production of highly diluted urine.

Alcohol does not block the flow of fluids through the kidney tubules.

Alcohol decreases the activity of antidiuretic hormone (vasopressin). A diuretic increases the production of urine and thus, inhibition of this _anti_diuretic hormone results in an increase in the production of highly diluted urine.

Alcohol does not block the flow of fluids through the kidney tubules.

Alcohol decreases the activity of antidiuretic hormone (vasopressin). A diuretic increases the production of urine and thus, inhibition of this _anti_diuretic hormone results in an increase in the production of highly diluted urine.

Alcohol does not block the flow of fluids through the kidney tubules.

The functional unit of the kidney is the nephron. Blood is filtered into the nephron to create filtrate. As the filtrate flows through the nephron tubules, its concentration is tightly regulated and ions and water are added and removed. The end result is a highly-concentrated filtrate that is transported to the bladder for excretion.

Neurons are the functional unit of the nervous system, not the kidney. Sarcomeres are the basic contractile unit of skeletal muscle, and chief cells are specialized stomach cells that secrete digestive enzymes, such as pepsinogen.

The functional unit of the kidney is the nephron. Blood is filtered into the nephron to create filtrate. As the filtrate flows through the nephron tubules, its concentration is tightly regulated and ions and water are added and removed. The end result is a highly-concentrated filtrate that is transported to the bladder for excretion.

Neurons are the functional unit of the nervous system, not the kidney. Sarcomeres are the basic contractile unit of skeletal muscle, and chief cells are specialized stomach cells that secrete digestive enzymes, such as pepsinogen.

The loop of Henle is essential for creating an ion gradient in the renal medulla (the inner part of the kidney). In the descending limb of the loop of Henle, water is removed from the filtrate by aquaporin proteins (water channels). The result is a highly concentrated filtrate at the bottom of the loop.

The filtrate then enters the thick ascending limb, which is permeable to sodium ions. The sodium ions rush out of the filtrate into the interstitium, which now has lower concentration than the filtrate. When the collecting duct later travels through the high concentration of sodium ions that have accumulated in the renal medulla from the thick ascending limb, water is pulled out of the filtrate into the interstitium. This allows for the final step in concentrating the urine before it travels to the bladder.

The functional unit of the kidney is the nephron. Blood is filtered into the nephron to create filtrate. As the filtrate flows through the nephron tubules, its concentration is tightly regulated and ions and water are added and removed. The end result is a highly-concentrated filtrate that is transported to the bladder for excretion.

Neurons are the functional unit of the nervous system, not the kidney. Sarcomeres are the basic contractile unit of skeletal muscle, and chief cells are specialized stomach cells that secrete digestive enzymes, such as pepsinogen.