Nitrogenous Wastes Quiz

PDF page 1419: Much information in this section is outside the scope for AP . However, the concepts provide an opportunity to apply concepts explored in previous chapters, including chemistry. Of the four macromolecules in biological systems, both proteins and nucleic acids contain nitrogen. During the breakdown (catabolism) of nitrogen-containing macromolecules, carbon, hydrogen, and oxygen are extracted and stored in the form of carbohydrates and fats. However, excess nitrogen must be excreted from the body because nitrogenous wastes tend to form toxic ammonia, which raises the pH of body fluids and disrupts homeostasis. The formation of toxic ammonia requires energy in the form of ATP and large quantities of water to dilute it out of a biological system. Aquatic animals, such as fishes, can release ammonia directly into the environment. Animals that excrete ammonia are said to be ammonotelic. Terrestrial animals, including mammals, must detoxify ammonia by converting it into relatively nontoxic forms such as uric acid or urea. Animals that secrete urea as the primary nitrogenous waste material are called ureotelic animals. Birds and reptiles excrete uric acid, a water-insoluble form of nitrogenous waste, thus reducing water loss. From an evolutionary standpoint, life likely started in an aquatic environment, so it not surprising that biochemical pathways like the conversion of ammonia to urea typical in mammals evolved to adapt to terrestrial conditions; more arid conditions probably led to the evolution of the uric acid pathway as a means of conserving water.

PDF page 1419: Much information in this section is outside the scope for AP . However, the concepts provide an opportunity to apply concepts explored in previous chapters, including chemistry. Of the four macromolecules in biological systems, both proteins and nucleic acids contain nitrogen. During the breakdown (catabolism) of nitrogen-containing macromolecules, carbon, hydrogen, and oxygen are extracted and stored in the form of carbohydrates and fats. However, excess nitrogen must be excreted from the body because nitrogenous wastes tend to form toxic ammonia, which raises the pH of body fluids and disrupts homeostasis. The formation of toxic ammonia requires energy in the form of ATP and large quantities of water to dilute it out of a biological system. Aquatic animals, such as fishes, can release ammonia directly into the environment. Animals that excrete ammonia are said to be ammonotelic. Terrestrial animals, including mammals, must detoxify ammonia by converting it into relatively nontoxic forms such as uric acid or urea. Animals that secrete urea as the primary nitrogenous waste material are called ureotelic animals. Birds and reptiles excrete uric acid, a water-insoluble form of nitrogenous waste, thus reducing water loss. From an evolutionary standpoint, life likely started in an aquatic environment, so it not surprising that biochemical pathways like the conversion of ammonia to urea typical in mammals evolved to adapt to terrestrial conditions; more arid conditions probably led to the evolution of the uric acid pathway as a means of conserving water.

PDF page 1419: Much information in this section is outside the scope for AP . However, the concepts provide an opportunity to apply concepts explored in previous chapters, including chemistry. Of the four macromolecules in biological systems, both proteins and nucleic acids contain nitrogen. During the breakdown (catabolism) of nitrogen-containing macromolecules, carbon, hydrogen, and oxygen are extracted and stored in the form of carbohydrates and fats. However, excess nitrogen must be excreted from the body because nitrogenous wastes tend to form toxic ammonia, which raises the pH of body fluids and disrupts homeostasis. The formation of toxic ammonia requires energy in the form of ATP and large quantities of water to dilute it out of a biological system. Aquatic animals, such as fishes, can release ammonia directly into the environment. Animals that excrete ammonia are said to be ammonotelic. Terrestrial animals, including mammals, must detoxify ammonia by converting it into relatively nontoxic forms such as uric acid or urea. Animals that secrete urea as the primary nitrogenous waste material are called ureotelic animals. Birds and reptiles excrete uric acid, a water-insoluble form of nitrogenous waste, thus reducing water loss. From an evolutionary standpoint, life likely started in an aquatic environment, so it not surprising that biochemical pathways like the conversion of ammonia to urea typical in mammals evolved to adapt to terrestrial conditions; more arid conditions probably led to the evolution of the uric acid pathway as a means of conserving water.

PDF page 1419: Much information in this section is outside the scope for AP . However, the concepts provide an opportunity to apply concepts explored in previous chapters, including chemistry. Of the four macromolecules in biological systems, both proteins and nucleic acids contain nitrogen. During the breakdown (catabolism) of nitrogen-containing macromolecules, carbon, hydrogen, and oxygen are extracted and stored in the form of carbohydrates and fats. However, excess nitrogen must be excreted from the body because nitrogenous wastes tend to form toxic ammonia, which raises the pH of body fluids and disrupts homeostasis. The formation of toxic ammonia requires energy in the form of ATP and large quantities of water to dilute it out of a biological system. Aquatic animals, such as fishes, can release ammonia directly into the environment. Animals that excrete ammonia are said to be ammonotelic. Terrestrial animals, including mammals, must detoxify ammonia by converting it into relatively nontoxic forms such as uric acid or urea. Animals that secrete urea as the primary nitrogenous waste material are called ureotelic animals. Birds and reptiles excrete uric acid, a water-insoluble form of nitrogenous waste, thus reducing water loss. From an evolutionary standpoint, life likely started in an aquatic environment, so it not surprising that biochemical pathways like the conversion of ammonia to urea typical in mammals evolved to adapt to terrestrial conditions; more arid conditions probably led to the evolution of the uric acid pathway as a means of conserving water.

PDF page 1419: Much information in this section is outside the scope for AP . However, the concepts provide an opportunity to apply concepts explored in previous chapters, including chemistry. Of the four macromolecules in biological systems, both proteins and nucleic acids contain nitrogen. During the breakdown (catabolism) of nitrogen-containing macromolecules, carbon, hydrogen, and oxygen are extracted and stored in the form of carbohydrates and fats. However, excess nitrogen must be excreted from the body because nitrogenous wastes tend to form toxic ammonia, which raises the pH of body fluids and disrupts homeostasis. The formation of toxic ammonia requires energy in the form of ATP and large quantities of water to dilute it out of a biological system. Aquatic animals, such as fishes, can release ammonia directly into the environment. Animals that excrete ammonia are said to be ammonotelic. Terrestrial animals, including mammals, must detoxify ammonia by converting it into relatively nontoxic forms such as uric acid or urea. Animals that secrete urea as the primary nitrogenous waste material are called ureotelic animals. Birds and reptiles excrete uric acid, a water-insoluble form of nitrogenous waste, thus reducing water loss. From an evolutionary standpoint, life likely started in an aquatic environment, so it not surprising that biochemical pathways like the conversion of ammonia to urea typical in mammals evolved to adapt to terrestrial conditions; more arid conditions probably led to the evolution of the uric acid pathway as a means of conserving water.

PDF page 1419: Much information in this section is outside the scope for AP . However, the concepts provide an opportunity to apply concepts explored in previous chapters, including chemistry. Of the four macromolecules in biological systems, both proteins and nucleic acids contain nitrogen. During the breakdown (catabolism) of nitrogen-containing macromolecules, carbon, hydrogen, and oxygen are extracted and stored in the form of carbohydrates and fats. However, excess nitrogen must be excreted from the body because nitrogenous wastes tend to form toxic ammonia, which raises the pH of body fluids and disrupts homeostasis. The formation of toxic ammonia requires energy in the form of ATP and large quantities of water to dilute it out of a biological system. Aquatic animals, such as fishes, can release ammonia directly into the environment. Animals that excrete ammonia are said to be ammonotelic. Terrestrial animals, including mammals, must detoxify ammonia by converting it into relatively nontoxic forms such as uric acid or urea. Animals that secrete urea as the primary nitrogenous waste material are called ureotelic animals. Birds and reptiles excrete uric acid, a water-insoluble form of nitrogenous waste, thus reducing water loss. From an evolutionary standpoint, life likely started in an aquatic environment, so it not surprising that biochemical pathways like the conversion of ammonia to urea typical in mammals evolved to adapt to terrestrial conditions; more arid conditions probably led to the evolution of the uric acid pathway as a means of conserving water.

PDF page 1419: Much information in this section is outside the scope for AP . However, the concepts provide an opportunity to apply concepts explored in previous chapters, including chemistry. Of the four macromolecules in biological systems, both proteins and nucleic acids contain nitrogen. During the breakdown (catabolism) of nitrogen-containing macromolecules, carbon, hydrogen, and oxygen are extracted and stored in the form of carbohydrates and fats. However, excess nitrogen must be excreted from the body because nitrogenous wastes tend to form toxic ammonia, which raises the pH of body fluids and disrupts homeostasis. The formation of toxic ammonia requires energy in the form of ATP and large quantities of water to dilute it out of a biological system. Aquatic animals, such as fishes, can release ammonia directly into the environment. Animals that excrete ammonia are said to be ammonotelic. Terrestrial animals, including mammals, must detoxify ammonia by converting it into relatively nontoxic forms such as uric acid or urea. Animals that secrete urea as the primary nitrogenous waste material are called ureotelic animals. Birds and reptiles excrete uric acid, a water-insoluble form of nitrogenous waste, thus reducing water loss. From an evolutionary standpoint, life likely started in an aquatic environment, so it not surprising that biochemical pathways like the conversion of ammonia to urea typical in mammals evolved to adapt to terrestrial conditions; more arid conditions probably led to the evolution of the uric acid pathway as a means of conserving water.

PDF page 1419: Much information in this section is outside the scope for AP . However, the concepts provide an opportunity to apply concepts explored in previous chapters, including chemistry. Of the four macromolecules in biological systems, both proteins and nucleic acids contain nitrogen. During the breakdown (catabolism) of nitrogen-containing macromolecules, carbon, hydrogen, and oxygen are extracted and stored in the form of carbohydrates and fats. However, excess nitrogen must be excreted from the body because nitrogenous wastes tend to form toxic ammonia, which raises the pH of body fluids and disrupts homeostasis. The formation of toxic ammonia requires energy in the form of ATP and large quantities of water to dilute it out of a biological system. Aquatic animals, such as fishes, can release ammonia directly into the environment. Animals that excrete ammonia are said to be ammonotelic. Terrestrial animals, including mammals, must detoxify ammonia by converting it into relatively nontoxic forms such as uric acid or urea. Animals that secrete urea as the primary nitrogenous waste material are called ureotelic animals. Birds and reptiles excrete uric acid, a water-insoluble form of nitrogenous waste, thus reducing water loss. From an evolutionary standpoint, life likely started in an aquatic environment, so it not surprising that biochemical pathways like the conversion of ammonia to urea typical in mammals evolved to adapt to terrestrial conditions; more arid conditions probably led to the evolution of the uric acid pathway as a means of conserving water.

PDF page 1420: The urea cycle is the primary mechanism by which mammals convert ammonia to urea. Urea is made in the liver and excreted in urine. The overall chemical reaction by which ammonia is converted to urea is 2 NH3 (ammonia) + CO2 + 3 ATP + H2O → H2N-CO-NH2 (urea) + 2 ADP + 4 Pi + AMP. The urea cycle utilizes five intermediate steps, catalyzed by five different enzymes, to convert ammonia to urea, as shown in Figure 32.13. The amino acid L-ornithine gets converted into different intermediates before being regenerated at the end of the urea cycle. Hence, the urea cycle is also referred to as the ornithine cycle. The enzyme ornithine transcarbamylase catalyzes a key step in the urea cycle and its deficiency can lead to accumulation of toxic levels of ammonia in the body. The first two reactions occur in the mitochondria and the last three reactions occur in the cytosol. Urea concentration in the blood, called blood urea nitrogen or BUN, is used as an indicator of kidney function.

PDF page 1420: The urea cycle is the primary mechanism by which mammals convert ammonia to urea. Urea is made in the liver and excreted in urine. The overall chemical reaction by which ammonia is converted to urea is 2 NH3 (ammonia) + CO2 + 3 ATP + H2O → H2N-CO-NH2 (urea) + 2 ADP + 4 Pi + AMP. The urea cycle utilizes five intermediate steps, catalyzed by five different enzymes, to convert ammonia to urea, as shown in Figure 32.13. The amino acid L-ornithine gets converted into different intermediates before being regenerated at the end of the urea cycle. Hence, the urea cycle is also referred to as the ornithine cycle. The enzyme ornithine transcarbamylase catalyzes a key step in the urea cycle and its deficiency can lead to accumulation of toxic levels of ammonia in the body. The first two reactions occur in the mitochondria and the last three reactions occur in the cytosol. Urea concentration in the blood, called blood urea nitrogen or BUN, is used as an indicator of kidney function.

PDF page 1420: The urea cycle is the primary mechanism by which mammals convert ammonia to urea. Urea is made in the liver and excreted in urine. The overall chemical reaction by which ammonia is converted to urea is 2 NH3 (ammonia) + CO2 + 3 ATP + H2O → H2N-CO-NH2 (urea) + 2 ADP + 4 Pi + AMP. The urea cycle utilizes five intermediate steps, catalyzed by five different enzymes, to convert ammonia to urea, as shown in Figure 32.13. The amino acid L-ornithine gets converted into different intermediates before being regenerated at the end of the urea cycle. Hence, the urea cycle is also referred to as the ornithine cycle. The enzyme ornithine transcarbamylase catalyzes a key step in the urea cycle and its deficiency can lead to accumulation of toxic levels of ammonia in the body. The first two reactions occur in the mitochondria and the last three reactions occur in the cytosol. Urea concentration in the blood, called blood urea nitrogen or BUN, is used as an indicator of kidney function.

PDF page 1420: The urea cycle is the primary mechanism by which mammals convert ammonia to urea. Urea is made in the liver and excreted in urine. The overall chemical reaction by which ammonia is converted to urea is 2 NH3 (ammonia) + CO2 + 3 ATP + H2O → H2N-CO-NH2 (urea) + 2 ADP + 4 Pi + AMP. The urea cycle utilizes five intermediate steps, catalyzed by five different enzymes, to convert ammonia to urea, as shown in Figure 32.13. The amino acid L-ornithine gets converted into different intermediates before being regenerated at the end of the urea cycle. Hence, the urea cycle is also referred to as the ornithine cycle. The enzyme ornithine transcarbamylase catalyzes a key step in the urea cycle and its deficiency can lead to accumulation of toxic levels of ammonia in the body. The first two reactions occur in the mitochondria and the last three reactions occur in the cytosol. Urea concentration in the blood, called blood urea nitrogen or BUN, is used as an indicator of kidney function.