Hemoglobin, Blood Cells, and Blood Proteins - MCAT Biological and Biochemical Foundations of Living Systems
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Albumin is created in the liver and is an important protein found in the blood. If a vial of blood is centrifuged, in which of the following layers would albumin be found?
Albumin is created in the liver and is an important protein found in the blood. If a vial of blood is centrifuged, in which of the following layers would albumin be found?
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When centrifuged, blood will divide into three parts: the plasma layer, the buffy coat layer, and the red blood cell layer. The plasma layer contains albumin, immunoglobulins, and blood clotting factors. The buffy coat is composed of leukocytes, and the red blood cell layer is composed of erythrocytes.
When centrifuged, blood will divide into three parts: the plasma layer, the buffy coat layer, and the red blood cell layer. The plasma layer contains albumin, immunoglobulins, and blood clotting factors. The buffy coat is composed of leukocytes, and the red blood cell layer is composed of erythrocytes.
Which of the following is known as "bad cholesterol"?
Which of the following is known as "bad cholesterol"?
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Low-density lipoprotein (LDL) cholesterol are considered to be "bad cholesterol" because it transports fat molecules to arteries and attracts macrophages, leading to atherosclerosis. Alternatively, high-density lipoprotein (HDL) cholesterol is considered to be "good cholesterol" because it removes fat molecules from macrophages, decreasing the risk of atherosclerosis.
Low-density lipoprotein (LDL) cholesterol are considered to be "bad cholesterol" because it transports fat molecules to arteries and attracts macrophages, leading to atherosclerosis. Alternatively, high-density lipoprotein (HDL) cholesterol is considered to be "good cholesterol" because it removes fat molecules from macrophages, decreasing the risk of atherosclerosis.
A scientist takes a group of erythrocytes (red blood cells) and places them in a beaker containing a solution. The cells begin to shrink and eventually lyse. What can be concluded about the solution?
A scientist takes a group of erythrocytes (red blood cells) and places them in a beaker containing a solution. The cells begin to shrink and eventually lyse. What can be concluded about the solution?
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Placing erythrocytes in a hypertonic solution would cause them to shrink and burst, becuase water from the erythrocytes would move from high to low concenration (inside the cells to the outside hypertonic environment). Albumin and bicarbonate would have no effect, because they are normal components of blood. Placing them in a hypotonic solution would cause them to swell up.
Placing erythrocytes in a hypertonic solution would cause them to shrink and burst, becuase water from the erythrocytes would move from high to low concenration (inside the cells to the outside hypertonic environment). Albumin and bicarbonate would have no effect, because they are normal components of blood. Placing them in a hypotonic solution would cause them to swell up.
A fetus does not breathe inside the womb, and so it must obtain oxygen a different way. What property of hemoglobin allows a fetus to recieve the oxyge it needs to develop?
A fetus does not breathe inside the womb, and so it must obtain oxygen a different way. What property of hemoglobin allows a fetus to recieve the oxyge it needs to develop?
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Fetal hemoglobin has a higher affinity for oxygen that adult hemoglobin. Maternal and Fetal blood never mix during pregnancy, but they come close to each other in the placenta. Oxygen diffuses easily to fetal hemoglobin here. The reason fetal hemoglobin has a higher affinity is it is composed of two alpha and two gamma subunits, while adult hemoglobin is composed of two alpha and two beta subunits.
Fetal hemoglobin has a higher affinity for oxygen that adult hemoglobin. Maternal and Fetal blood never mix during pregnancy, but they come close to each other in the placenta. Oxygen diffuses easily to fetal hemoglobin here. The reason fetal hemoglobin has a higher affinity is it is composed of two alpha and two gamma subunits, while adult hemoglobin is composed of two alpha and two beta subunits.
Which of the following is a cause of alkalosis?
Which of the following is a cause of alkalosis?
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Hyperventilation is a classic example of a process that can cause alkalosis, or basicity of the bloodstream. Hyperventilation can cause a net loss of CO2. Low levels of CO2 can cause respiratory alkalosis via reduction of carbonate in the blood. Lactate—also known as lactic acid—is a product of anaerobic respiration, and decreases blood pH. Increased levels of urea and creatinine indicate renal acidosis, a form of metabolic acidosis, which occurs when the kidney does not remove enough acid from the body.
Hyperventilation is a classic example of a process that can cause alkalosis, or basicity of the bloodstream. Hyperventilation can cause a net loss of CO2. Low levels of CO2 can cause respiratory alkalosis via reduction of carbonate in the blood. Lactate—also known as lactic acid—is a product of anaerobic respiration, and decreases blood pH. Increased levels of urea and creatinine indicate renal acidosis, a form of metabolic acidosis, which occurs when the kidney does not remove enough acid from the body.
What could the blood pH of a person who has blood acidosis (more acidic blood than normal) possibly be?
What could the blood pH of a person who has blood acidosis (more acidic blood than normal) possibly be?
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The normal pH of blood is around 7.3, which means blood is normally slightly basic. A truly neutral pH is 7.0. Whenever the pH of blood is under 7.3 (not 7.0) it is considered acidosis, and so our answer is either 7.2 or 6.8.
The normal pH of blood is around 7.3, which means blood is normally slightly basic. A truly neutral pH is 7.0. Whenever the pH of blood is under 7.3 (not 7.0) it is considered acidosis, and so our answer is either 7.2 or 6.8.
Which factors contribute to the Bohr Effect?
Which factors contribute to the Bohr Effect?
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The Bohr Effect describes hemoglobin's affinty for oxygen as a function of blood pH and carbon dioxide content. An increase in CO2 concentration will lower the blood pH, causing the hemoglobin affinity for oxygen to reduce. High temperature also causes oxygen to be released from hemoglobin, but is not related to the Bohr Effect.
Think about when you're exercising. Your blood has a reduced O2 concentration and an elevated CO2 concentration. These factors allow hemoglobin to release more oxygen in the muscles to faciliate ATP production and maintain energy levels.
The Bohr Effect describes hemoglobin's affinty for oxygen as a function of blood pH and carbon dioxide content. An increase in CO2 concentration will lower the blood pH, causing the hemoglobin affinity for oxygen to reduce. High temperature also causes oxygen to be released from hemoglobin, but is not related to the Bohr Effect.
Think about when you're exercising. Your blood has a reduced O2 concentration and an elevated CO2 concentration. These factors allow hemoglobin to release more oxygen in the muscles to faciliate ATP production and maintain energy levels.
Hemoglobin is the principal oxygen-carrying protein in humans. It exists within erythrocytes, and binds up to four diatomic oxygen molecules simultaneously. Hemoglobin functions to maximize oxygen delivery to tissues, while simultaneously maximizing oxygen absorption in the lungs. Hemoglobin thus has a fundamentally contradictory set of goals. It must at once be optimized to absorb oxygen, and to offload oxygen. Natural selection has overcome this apparent contradiction by making hemoglobin exquisitely sensitive to conditions in its microenvironment.
One way in which hemoglobin accomplishes its goals is through the phenomenon of cooperativity. Cooperativity refers to the ability of hemoglobin to change its oxygen binding behavior as a function of how many other oxygen atoms are bound to the molecule.
Fetal hemoglobin shows a similar pattern of cooperativity, but has unique binding characteristics relative to adult hemoglobin. Fetal hemoglobin reaches higher saturation at lower oxygen partial pressure.
Because of cooperativity, adult and fetal oxygen-hemoglobin dissociation curves appear as follows.
Beyond its ability to carry oxygen, hemoglobin is also effective as a blood buffer. The general reaction for the blood buffer system of hemoglobin is given below.
H+ + HbO2 ←→ H+Hb + O2
Considering the described oxygen affinity pattern for hemoglobin, which curve is likely to depict fetal hemoglobin?
Hemoglobin is the principal oxygen-carrying protein in humans. It exists within erythrocytes, and binds up to four diatomic oxygen molecules simultaneously. Hemoglobin functions to maximize oxygen delivery to tissues, while simultaneously maximizing oxygen absorption in the lungs. Hemoglobin thus has a fundamentally contradictory set of goals. It must at once be optimized to absorb oxygen, and to offload oxygen. Natural selection has overcome this apparent contradiction by making hemoglobin exquisitely sensitive to conditions in its microenvironment.
One way in which hemoglobin accomplishes its goals is through the phenomenon of cooperativity. Cooperativity refers to the ability of hemoglobin to change its oxygen binding behavior as a function of how many other oxygen atoms are bound to the molecule.
Fetal hemoglobin shows a similar pattern of cooperativity, but has unique binding characteristics relative to adult hemoglobin. Fetal hemoglobin reaches higher saturation at lower oxygen partial pressure.
Because of cooperativity, adult and fetal oxygen-hemoglobin dissociation curves appear as follows.
Beyond its ability to carry oxygen, hemoglobin is also effective as a blood buffer. The general reaction for the blood buffer system of hemoglobin is given below.
H+ + HbO2 ←→ H+Hb + O2
Considering the described oxygen affinity pattern for hemoglobin, which curve is likely to depict fetal hemoglobin?
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Curve 1 shows greater affinity for oxygen than curve 2, as it is higher up the y-axis at any single point on the x-axis. We would expect this finding for fetal hemoglobin, which would need to extract oxygen from maternal blood.
Curve 1 shows greater affinity for oxygen than curve 2, as it is higher up the y-axis at any single point on the x-axis. We would expect this finding for fetal hemoglobin, which would need to extract oxygen from maternal blood.
Hemoglobin is the principal oxygen-carrying protein in humans. It exists within erythrocytes, and binds up to four diatomic oxygen molecules simultaneously. Hemoglobin functions to maximize oxygen delivery to tissues, while simultaneously maximizing oxygen absorption in the lungs. Hemoglobin thus has a fundamentally contradictory set of goals. It must at once be optimized to absorb oxygen, and to offload oxygen. Natural selection has overcome this apparent contradiction by making hemoglobin exquisitely sensitive to conditions in its microenvironment.
One way in which hemoglobin accomplishes its goals is through the phenomenon of cooperativity. Cooperativity refers to the ability of hemoglobin to change its oxygen binding behavior as a function of how many other oxygen atoms are bound to the molecule.
Fetal hemoglobin shows a similar pattern of cooperativity, but has unique binding characteristics relative to adult hemoglobin. Fetal hemoglobin reaches higher saturation at lower oxygen partial pressure.
Because of cooperativity, adult and fetal oxygen-hemoglobin dissociation curves appear as follows.
Beyond its ability to carry oxygen, hemoglobin is also effective as a blood buffer. The general reaction for the blood buffer system of hemoglobin given below.
H+ + HbO2 ←→ H+Hb + O2
Hemoglobin is the most important component of red blood cells. How are red blood cells different from other cells of the body?
Hemoglobin is the principal oxygen-carrying protein in humans. It exists within erythrocytes, and binds up to four diatomic oxygen molecules simultaneously. Hemoglobin functions to maximize oxygen delivery to tissues, while simultaneously maximizing oxygen absorption in the lungs. Hemoglobin thus has a fundamentally contradictory set of goals. It must at once be optimized to absorb oxygen, and to offload oxygen. Natural selection has overcome this apparent contradiction by making hemoglobin exquisitely sensitive to conditions in its microenvironment.
One way in which hemoglobin accomplishes its goals is through the phenomenon of cooperativity. Cooperativity refers to the ability of hemoglobin to change its oxygen binding behavior as a function of how many other oxygen atoms are bound to the molecule.
Fetal hemoglobin shows a similar pattern of cooperativity, but has unique binding characteristics relative to adult hemoglobin. Fetal hemoglobin reaches higher saturation at lower oxygen partial pressure.
Because of cooperativity, adult and fetal oxygen-hemoglobin dissociation curves appear as follows.
Beyond its ability to carry oxygen, hemoglobin is also effective as a blood buffer. The general reaction for the blood buffer system of hemoglobin given below.
H+ + HbO2 ←→ H+Hb + O2
Hemoglobin is the most important component of red blood cells. How are red blood cells different from other cells of the body?
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Red blood cells are unique in that they lack a nucleus and are functionally just "bags of hemoglobin." They are among the most specialized cells, doing little else but transporting oxygen in the blood.
The choice indicating protein support for the membrane may have also been tempting, and is true. This characteristic, however, is shared by other cells of the body. Also remember that red blood cells are produced by red bone marrow (and sometimes the liver), while certain white blood cells mature in the thymus.
Red blood cells are unique in that they lack a nucleus and are functionally just "bags of hemoglobin." They are among the most specialized cells, doing little else but transporting oxygen in the blood.
The choice indicating protein support for the membrane may have also been tempting, and is true. This characteristic, however, is shared by other cells of the body. Also remember that red blood cells are produced by red bone marrow (and sometimes the liver), while certain white blood cells mature in the thymus.
Hemoglobin is the principal oxygen-carrying protein in humans. It exists within erythrocytes, and binds up to four diatomic oxygen molecules simultaneously. Hemoglobin functions to maximize oxygen delivery to tissues, while simultaneously maximizing oxygen absorption in the lungs. Hemoglobin thus has a fundamentally contradictory set of goals. It must at once be optimized to absorb oxygen, and to offload oxygen. Natural selection has overcome this apparent contradiction by making hemoglobin exquisitely sensitive to conditions in its microenvironment.
One way in which hemoglobin accomplishes its goals is through the phenomenon of cooperativity. Cooperativity refers to the ability of hemoglobin to change its oxygen binding behavior as a function of how many other oxygen atoms are bound to the molecule.
Fetal hemoglobin shows a similar pattern of cooperativity, but has unique binding characteristics relative to adult hemoglobin. Fetal hemoglobin reaches higher saturation at lower oxygen partial pressure.
Because of cooperativity, adult and fetal oxygen-hemoglobin dissociation curves appear as follows.
Beyond its ability to carry oxygen, hemoglobin is also effective as a blood buffer. The general reaction for the blood buffer system of hemoglobin is given below.
H+ + HbO2 ←→ H+Hb + O2
Based on the above graph, which of the following would be expected when oxygen unloads from hemoglobin?
Hemoglobin is the principal oxygen-carrying protein in humans. It exists within erythrocytes, and binds up to four diatomic oxygen molecules simultaneously. Hemoglobin functions to maximize oxygen delivery to tissues, while simultaneously maximizing oxygen absorption in the lungs. Hemoglobin thus has a fundamentally contradictory set of goals. It must at once be optimized to absorb oxygen, and to offload oxygen. Natural selection has overcome this apparent contradiction by making hemoglobin exquisitely sensitive to conditions in its microenvironment.
One way in which hemoglobin accomplishes its goals is through the phenomenon of cooperativity. Cooperativity refers to the ability of hemoglobin to change its oxygen binding behavior as a function of how many other oxygen atoms are bound to the molecule.
Fetal hemoglobin shows a similar pattern of cooperativity, but has unique binding characteristics relative to adult hemoglobin. Fetal hemoglobin reaches higher saturation at lower oxygen partial pressure.
Because of cooperativity, adult and fetal oxygen-hemoglobin dissociation curves appear as follows.
Beyond its ability to carry oxygen, hemoglobin is also effective as a blood buffer. The general reaction for the blood buffer system of hemoglobin is given below.
H+ + HbO2 ←→ H+Hb + O2
Based on the above graph, which of the following would be expected when oxygen unloads from hemoglobin?
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The basic idea of cooperativity is that oxygen will bind with lower affinity once an oxygen atom is removed. Once you remove the first oxygen atom, the remaining ones are more likely to come off to supply tissue. This change is instigated by conformational changes in hemoglobin structure when an oxygen is removed.
The basic idea of cooperativity is that oxygen will bind with lower affinity once an oxygen atom is removed. Once you remove the first oxygen atom, the remaining ones are more likely to come off to supply tissue. This change is instigated by conformational changes in hemoglobin structure when an oxygen is removed.
Hemoglobin is the principal oxygen-carrying protein in humans. It exists within erythrocytes, and binds up to four diatomic oxygen molecules simultaneously. Hemoglobin functions to maximize oxygen delivery to tissues, while simultaneously maximizing oxygen absorption in the lungs. Hemoglobin thus has a fundamentally contradictory set of goals. It must at once be opitimized to absorb oxygen, and to offload oxygen. Natural selection has overcome this apparent contradiction by making hemoglobin exquisitely sensitive to conditions in its microenvironment.
One way in which hemoglobin accomplishes its goals is through the phenomenon of cooperativity. Cooperativity refers to the ability of hemoglobin to change its oxygen binding behavior as a function of how many other oxygen atoms are bound to the molecule.
Fetal hemoglobin shows a similar pattern of cooperativity, but has unique binding characteristics relative to adult hemoglobin. Fetal hemoglobin reaches higher saturation at lower oxygen partial pressure.
Because of cooperativity, adult and fetal oxygen-hemoglobin dissociation curves appear as follows.
Beyond its ability to carry oxygen, hemoglobin is also effective as a blood buffer. The general reaction for the blood buffer system of hemoglobin is given below.
H+ + HbO2 ←→ H+Hb + O2
Myoglobin is a similar carrier molecule to hemoglobin, but it only has one site of oxygen binding instead of four. Which characteristic of hemoglobin is most likely not shared by myoglobin?
Hemoglobin is the principal oxygen-carrying protein in humans. It exists within erythrocytes, and binds up to four diatomic oxygen molecules simultaneously. Hemoglobin functions to maximize oxygen delivery to tissues, while simultaneously maximizing oxygen absorption in the lungs. Hemoglobin thus has a fundamentally contradictory set of goals. It must at once be opitimized to absorb oxygen, and to offload oxygen. Natural selection has overcome this apparent contradiction by making hemoglobin exquisitely sensitive to conditions in its microenvironment.
One way in which hemoglobin accomplishes its goals is through the phenomenon of cooperativity. Cooperativity refers to the ability of hemoglobin to change its oxygen binding behavior as a function of how many other oxygen atoms are bound to the molecule.
Fetal hemoglobin shows a similar pattern of cooperativity, but has unique binding characteristics relative to adult hemoglobin. Fetal hemoglobin reaches higher saturation at lower oxygen partial pressure.
Because of cooperativity, adult and fetal oxygen-hemoglobin dissociation curves appear as follows.
Beyond its ability to carry oxygen, hemoglobin is also effective as a blood buffer. The general reaction for the blood buffer system of hemoglobin is given below.
H+ + HbO2 ←→ H+Hb + O2
Myoglobin is a similar carrier molecule to hemoglobin, but it only has one site of oxygen binding instead of four. Which characteristic of hemoglobin is most likely not shared by myoglobin?
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Cooperativity, as defined in the passage, requires more than one binding site. Without more than one binding site, it is impossible for a carrier to change its affinity for additional cargo after the first piece is either loaded or unloaded. That additional cargo simply doesn't exist for myoglobin.
Cooperativity, as defined in the passage, requires more than one binding site. Without more than one binding site, it is impossible for a carrier to change its affinity for additional cargo after the first piece is either loaded or unloaded. That additional cargo simply doesn't exist for myoglobin.
Hemoglobin is the principal oxygen-carrying protein in humans. It exists within erythrocytes, and binds up to four diatomic oxygen molecules simultaneously. Hemoglobin functions to maximize oxygen delivery to tissues, while simultaneously maximizing oxygen absorption in the lungs. Hemoglobin thus has a fundamentally contradictory set of goals. It must at once be opitimized to absorb oxygen, and to offload oxygen. Natural selection has overcome this apparent contradiction by making hemoglobin exquisitely sensitive to conditions in its microenvironment.
One way in which hemoglobin accomplishes its goals is through the phenomenon of cooperativity. Cooperativity refers to the ability of hemoglobin to change its oxygen binding behavior as a function of how many other oxygen atoms are bound to the molecule.
Fetal hemoglobin shows a similar pattern of cooperativity, but has unique binding characteristics relative to adult hemoglobin. Fetal hemoglobin reaches higher saturation at lower oxygen partial pressure.
Because of cooperativity, adult and fetal oxygen-hemoglobin dissociation curves appear as follows.
Beyond its ability to carry oxygen, hemoglobin is also effective as a blood buffer. The general reaction for the blood buffer system of hemoglobin is given below.
H+ + HbO2 ←→ H+Hb + O2
While most of the oxygen transported in blood is bound to hemoglobin, only a small fraction of carbon dioxide (CO2) present in blood is transported via this carrier. Most is dissolved in blood in an alternative form. Why does CO2 need to be changed to an alternative form to dissolve into blood?
Hemoglobin is the principal oxygen-carrying protein in humans. It exists within erythrocytes, and binds up to four diatomic oxygen molecules simultaneously. Hemoglobin functions to maximize oxygen delivery to tissues, while simultaneously maximizing oxygen absorption in the lungs. Hemoglobin thus has a fundamentally contradictory set of goals. It must at once be opitimized to absorb oxygen, and to offload oxygen. Natural selection has overcome this apparent contradiction by making hemoglobin exquisitely sensitive to conditions in its microenvironment.
One way in which hemoglobin accomplishes its goals is through the phenomenon of cooperativity. Cooperativity refers to the ability of hemoglobin to change its oxygen binding behavior as a function of how many other oxygen atoms are bound to the molecule.
Fetal hemoglobin shows a similar pattern of cooperativity, but has unique binding characteristics relative to adult hemoglobin. Fetal hemoglobin reaches higher saturation at lower oxygen partial pressure.
Because of cooperativity, adult and fetal oxygen-hemoglobin dissociation curves appear as follows.
Beyond its ability to carry oxygen, hemoglobin is also effective as a blood buffer. The general reaction for the blood buffer system of hemoglobin is given below.
H+ + HbO2 ←→ H+Hb + O2
While most of the oxygen transported in blood is bound to hemoglobin, only a small fraction of carbon dioxide (CO2) present in blood is transported via this carrier. Most is dissolved in blood in an alternative form. Why does CO2 need to be changed to an alternative form to dissolve into blood?
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Carbon dioxide (CO2) is nonpolar, and thus can dissolve well only in nonpolar solvents. Since blood is an aqueous (and polar) solvent, CO2 needs to be converted to a polar form via blood enzymes to allow it to be dissolved directly in water.
Carbon dioxide (CO2) is nonpolar, and thus can dissolve well only in nonpolar solvents. Since blood is an aqueous (and polar) solvent, CO2 needs to be converted to a polar form via blood enzymes to allow it to be dissolved directly in water.
Which statement regarding blood typing is correct?
Which statement regarding blood typing is correct?
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The AB+ blood type is known as the "universal recipient" type, therefore, people with any blood type can donate to an AB+ individual.
As for the incorrect answers, a person with O- blood has the "universal donor" type, and can only receive blood from other O- individuals. Erythroblastosis fetalis, also known as hemolytic disease of the newborn, cannot occur during a woman's first pregnancy because her body has not yet produced anti-Rh antibodies. Finally, Rh factor presence is a genetically dominant condition.
The AB+ blood type is known as the "universal recipient" type, therefore, people with any blood type can donate to an AB+ individual.
As for the incorrect answers, a person with O- blood has the "universal donor" type, and can only receive blood from other O- individuals. Erythroblastosis fetalis, also known as hemolytic disease of the newborn, cannot occur during a woman's first pregnancy because her body has not yet produced anti-Rh antibodies. Finally, Rh factor presence is a genetically dominant condition.
Which of the following gases can be bound by hemoglobin?
Which of the following gases can be bound by hemoglobin?
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All of these gases can be bound by hemoglobin. Hemoglobin transports oxygen from the lungs to the necessary tissue, and carbon dioxide from the tissue to the lungs. Hemoglobin has a much higher affinity for carbon monoxide than oxygen, which is why it is so dangerous to inhale carbon monoxide.
All of these gases can be bound by hemoglobin. Hemoglobin transports oxygen from the lungs to the necessary tissue, and carbon dioxide from the tissue to the lungs. Hemoglobin has a much higher affinity for carbon monoxide than oxygen, which is why it is so dangerous to inhale carbon monoxide.
Which of the following accurately represents the entire composition of blood?
Which of the following accurately represents the entire composition of blood?
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Human blood contains 55% plasma and 45% cells. The cells include erythrocytes (red blood cells), leukocytes (white blood cells), and thrombocytes (platelets). Plasma is largely composed of water, protein (albumin), and clotting factors.
Note that blood serum is simply blood plasma with the clotting factor elements (fibrinogen) removed.
Human blood contains 55% plasma and 45% cells. The cells include erythrocytes (red blood cells), leukocytes (white blood cells), and thrombocytes (platelets). Plasma is largely composed of water, protein (albumin), and clotting factors.
Note that blood serum is simply blood plasma with the clotting factor elements (fibrinogen) removed.
Coagulation factor II, also called prothrombin, plays an important role in the clotting process. A very rare genetic mutation causes a deficiency of coagulation factor II, resulting in a form of hemophilia due to a mutation affecting a protein produced by which organ?
Coagulation factor II, also called prothrombin, plays an important role in the clotting process. A very rare genetic mutation causes a deficiency of coagulation factor II, resulting in a form of hemophilia due to a mutation affecting a protein produced by which organ?
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Coagulation Factor II (prothrombin) is a protein produced in the liver. Prothrombin is modified after translation to produce thrombin. Thrombin is an enzyme that catalyzes coagulation reactions and results in reduced blood loss. Factor II deficiency is an autosomal recessive mutation that can result in defects in blood clotting.
Coagulation Factor II (prothrombin) is a protein produced in the liver. Prothrombin is modified after translation to produce thrombin. Thrombin is an enzyme that catalyzes coagulation reactions and results in reduced blood loss. Factor II deficiency is an autosomal recessive mutation that can result in defects in blood clotting.
Which of the following most accurately depicts the process of clotting?
Which of the following most accurately depicts the process of clotting?
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Thromboplastin is released when damage occurs to a tissue. Prothrombin and fibrinogen are both present in the blood. When thromboplastin interacts with the blood, it converts prothrombin to its active state, thrombin. Thrombin then cleaves fibrinogen, converting it to its active state, fibrin. Fibrin is exceptional at forming cross-linked mesh-like interactions, and in doing so traps passing blood cells and plasma proteins. This blockage and accumulation of blood elements becomes the clot.
Thromboplastin is released when damage occurs to a tissue. Prothrombin and fibrinogen are both present in the blood. When thromboplastin interacts with the blood, it converts prothrombin to its active state, thrombin. Thrombin then cleaves fibrinogen, converting it to its active state, fibrin. Fibrin is exceptional at forming cross-linked mesh-like interactions, and in doing so traps passing blood cells and plasma proteins. This blockage and accumulation of blood elements becomes the clot.
Which of the following gases can bind to hemoglobin?
Which of the following gases can bind to hemoglobin?
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Hemoglobin can bind to all three of these gases, however, it binds to each of them with a different affinity. Hemoglobin's affinity for the three gases, from highest to lowest, is listed below.
carbon monoxide (CO) > oxygen (O2) > carbon dioxide (CO2).
Note that cabron monoxide has the highest affininty; this is why is can be dangerous to inhale too much carbon monoxide, as it will displace onxygen that would otherwise bind to hemoglobin.
Hemoglobin can bind to all three of these gases, however, it binds to each of them with a different affinity. Hemoglobin's affinity for the three gases, from highest to lowest, is listed below.
carbon monoxide (CO) > oxygen (O2) > carbon dioxide (CO2).
Note that cabron monoxide has the highest affininty; this is why is can be dangerous to inhale too much carbon monoxide, as it will displace onxygen that would otherwise bind to hemoglobin.
Fetal circulation differs greatly from that of adults. For example, a fetus does not actually have functional lungs until birth, and instead receives oxygen from the mother umbilical vein. Which is not an adaptation of the fetal circulatory system?
Fetal circulation differs greatly from that of adults. For example, a fetus does not actually have functional lungs until birth, and instead receives oxygen from the mother umbilical vein. Which is not an adaptation of the fetal circulatory system?
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Most adaptations of the fetal circulatory system are designed to bypass the lungs and liver, which develop especially slowly. The ductus venosus shuttles blood directly from the umbilical vein to the inferior vena cava, avoiding the liver entirely. The foramen ovale is a right-to-left shunt between the atria that sends blood away from the right ventricle; the ductus arteriosus shunts the remaining blood from the right ventricle to the aorta to bypass the lungs. Finally, fetal hemoglobin has a high affinity for oxygen because it must compete with maternal blood in the placenta.
Fetal myoglobin does not have a low affinity for oxygen.
Most adaptations of the fetal circulatory system are designed to bypass the lungs and liver, which develop especially slowly. The ductus venosus shuttles blood directly from the umbilical vein to the inferior vena cava, avoiding the liver entirely. The foramen ovale is a right-to-left shunt between the atria that sends blood away from the right ventricle; the ductus arteriosus shunts the remaining blood from the right ventricle to the aorta to bypass the lungs. Finally, fetal hemoglobin has a high affinity for oxygen because it must compete with maternal blood in the placenta.
Fetal myoglobin does not have a low affinity for oxygen.
Which of the following is most likely to decrease oxygen's affinity to hemoglobin in the bloodstream?
Which of the following is most likely to decrease oxygen's affinity to hemoglobin in the bloodstream?
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High levels of carbon dioxide (CO2), low pH, and high temperatures all act to decrease oxygen's affinity toward human hemoglobin. Think of working muscle, which produces hot, acidic, high CO2 conditions in the blood; in this environment, it is important for hemoglobin to release transported oxygen to provide an aerobic environment to the muscle.
High levels of carbon dioxide (CO2), low pH, and high temperatures all act to decrease oxygen's affinity toward human hemoglobin. Think of working muscle, which produces hot, acidic, high CO2 conditions in the blood; in this environment, it is important for hemoglobin to release transported oxygen to provide an aerobic environment to the muscle.