1.
Plasma thromboplastin is a factor in the ________ pathway
Correct Answer
D. Intrinsic
Explanation
Plasma thromboplastin is a factor in the intrinsic pathway. This pathway is one of the two main pathways involved in blood clot formation. The intrinsic pathway is activated when there is damage to the blood vessel wall, leading to the release of plasma thromboplastin. This factor then initiates a cascade of reactions that ultimately result in the formation of a blood clot. The extrinsic pathway, on the other hand, is activated by tissue factor released from damaged tissue outside of the blood vessel.
2.
A moving blood clot is called a(n)
Correct Answer
B. Embolus.
Explanation
A moving blood clot is called an embolus. An embolus is a clot that breaks away from its original location and travels through the bloodstream to another part of the body, where it can block blood flow and cause various complications depending on where it lodges.
3.
Plasma is closest in composition to
Correct Answer
A. Interstitial fluid.
Explanation
Plasma is closest in composition to interstitial fluid because both contain similar concentrations of electrolytes, hormones, and nutrients. Interstitial fluid surrounds and bathes cells, providing them with necessary substances and removing waste products. Plasma, on the other hand, is the liquid component of blood that carries nutrients, hormones, and waste products throughout the body. Both fluids are essential for maintaining homeostasis and ensuring proper functioning of cells and tissues.
4.
Which of the following is present in very low levels in plasma
Correct Answer
E. Amino acids
Explanation
Amino acids are the building blocks of proteins and are essential for various biological processes. They are primarily obtained from the breakdown of proteins in the body or from dietary sources. While albumin, electrolytes, platelets, and fibrinogen are all present in relatively higher levels in plasma and play important roles in maintaining bodily functions, amino acids are present in very low levels in plasma as they are rapidly taken up by cells for protein synthesis or other metabolic processes.
5.
Plasma composes about ________ percent of whole blood and water composes ________ percent of the plasma volume.
Correct Answer
C. 55, 92
Explanation
Plasma makes up about 55 percent of whole blood, while water makes up about 92 percent of the plasma volume.
6.
Which plasma protein transports fatty acids and some hormones?
Correct Answer
D. Albumin
Explanation
Albumin is a plasma protein that transports fatty acids and some hormones. It is the most abundant protein in the blood and plays a crucial role in maintaining osmotic pressure, pH balance, and transporting various substances throughout the body. Due to its ability to bind to fatty acids and hormones, albumin acts as a carrier molecule, ensuring their safe transport to different tissues and organs.
7.
Which of the following proteins is (are) found in plasma
Correct Answer
D. All of the above
Explanation
All of the proteins mentioned in the options (luteinizing hormone, insulin, and prolactin) are found in plasma. Plasma is the liquid component of blood and contains various proteins, including hormones like luteinizing hormone, insulin, and prolactin. These proteins play important roles in regulating various physiological processes in the body. Therefore, the correct answer is all of the above.
8.
The most abundant white blood cells are
Correct Answer
D. NeutropHils
Explanation
Neutrophils are the most abundant white blood cells in the body. They play a crucial role in the immune system by engulfing and destroying bacteria and other foreign substances. They are highly mobile and are the first responders to sites of infection or inflammation. Neutrophils are characterized by their multi-lobed nucleus and granular cytoplasm. Their abundance and rapid response make them an essential component of the body's defense against infections.
9.
Which of the following blood count values would be a sign of anemia
Correct Answer
D. 3.5 million RBC
Explanation
A normal range for red blood cell (RBC) count in adults is typically between 4.5 to 5.5 million cells per microliter of blood. A value of 3.5 million RBCs would be lower than the normal range, indicating a lower than normal RBC count. This can be a sign of anemia, a condition characterized by a decrease in the number of red blood cells or a decrease in the amount of hemoglobin in the blood. Anemia can result in symptoms such as fatigue, weakness, and shortness of breath.
10.
Which of these descriptions best matches the term T lymphocytes
Correct Answer
C. Helper cells are one type
Explanation
T lymphocytes, also known as T cells, are a type of white blood cell that play a crucial role in the immune response. They are responsible for recognizing and destroying infected cells, as well as coordinating the immune system's response to pathogens. Helper T cells are a specific type of T lymphocyte that help regulate and enhance the immune response by activating other immune cells. Therefore, the description "helper cells are one type" best matches the term T lymphocytes.
11.
After donating 0.5 liter of blood, one would expect
Correct Answer
E. An increased reticulocyte count.
Explanation
After donating blood, the body needs to replace the lost red blood cells. Reticulocytes are immature red blood cells that are released into the bloodstream to replace the lost ones. Therefore, it is expected that the reticulocyte count will increase after donating blood.
12.
A hematocrit provides information on
Correct Answer
E. Formed elements abundance.
Explanation
A hematocrit measures the percentage of red blood cells in the total blood volume. Red blood cells are one of the formed elements in the blood, along with white blood cells and platelets. By determining the abundance of formed elements, a hematocrit provides information about the overall cellular composition of the blood. It does not provide information about plasma composition, clotting factors, blood type, or sedimentation rate.
13.
The most numerous WBCs in a differential count of a healthy individual are
Correct Answer
D. NeutropHils.
Explanation
Neutrophils are the most numerous white blood cells (WBCs) in a differential count of a healthy individual. They play a crucial role in the immune system's response to bacterial infections. Neutrophils are highly mobile and quickly migrate to the site of infection, where they engulf and destroy bacteria through a process called phagocytosis. Their abundance in the differential count indicates a healthy immune system capable of effectively combating bacterial pathogens.
14.
) Each heme ring in hemoglobin encloses an atom of
Correct Answer
A. Iron
Explanation
Hemoglobin is a protein found in red blood cells that is responsible for carrying oxygen throughout the body. Each heme ring in hemoglobin contains an iron atom, which is essential for the binding and transport of oxygen. Iron binds to oxygen in the lungs and releases it to tissues that need oxygen for cellular respiration. Without iron, hemoglobin would not be able to perform its crucial role in oxygen transport, leading to severe health problems such as anemia. Therefore, the correct answer is iron.
15.
Which of these descriptions best matches the term eosinophils?
Correct Answer
D. Often elevated in allergic individuals
Explanation
Eosinophils are a type of white blood cell that are often elevated in allergic individuals. They play a role in the immune response to parasitic infections and are involved in the inflammatory response associated with allergies. They release chemicals that help to destroy parasites and are also involved in the regulation of inflammation. Therefore, the description "often elevated in allergic individuals" best matches the term eosinophils.
16.
Which of these proteins functions to store or transport iron?
Correct Answer
E. B, C, and D
Explanation
The proteins transferrin, hemosiderin, and ferritin all function to store or transport iron. Transferrin is a protein that binds to iron in the bloodstream and transports it to cells. Hemosiderin is a protein complex that stores excess iron in tissues. Ferritin is a protein that also stores iron, primarily in the liver, spleen, and bone marrow. Therefore, the correct answer is B, C, and D.
17.
The pus associated with infected wounds contains
Correct Answer
D. All of the above
Explanation
The pus associated with infected wounds contains cellular debris, dead neutrophils, and tissue fluids. This is because when a wound becomes infected, the body's immune system sends white blood cells, mainly neutrophils, to fight off the infection. These neutrophils die in the process and along with other cellular debris and tissue fluids, they form pus. Therefore, all of the options mentioned in the answer are correct.
18.
A substance that activates plasminogen might be useful to
Correct Answer
C. Cause clot dissolution to proceed faster
Explanation
A substance that activates plasminogen can cause clot dissolution to proceed faster. Plasminogen is an inactive form of plasmin, an enzyme that breaks down blood clots. When plasminogen is activated, it is converted into plasmin, which can degrade the fibrin meshwork that holds a blood clot together. By accelerating the process of clot dissolution, this substance can help in preventing the formation of large and obstructive blood clots, reducing the risk of complications such as stroke or heart attack.
19.
Surgical removal of the stomach could cause
Correct Answer
B. Pernicious anemia
Explanation
The surgical removal of the stomach can lead to pernicious anemia. Pernicious anemia is a condition where the body is unable to absorb enough vitamin B12 from the gastrointestinal tract. The stomach plays a crucial role in the absorption of this vitamin. Without a stomach, the body's ability to absorb vitamin B12 is greatly reduced, leading to pernicious anemia. This condition can cause fatigue, weakness, shortness of breath, and other symptoms due to a deficiency in vitamin B12.
20.
An obstruction in blood flow to the kidneys would ultimately result in
Correct Answer
C. Increased erythropoiesis
Explanation
When there is an obstruction in blood flow to the kidneys, it can lead to decreased oxygen supply to the kidneys. This triggers the release of a hormone called erythropoietin, which stimulates the bone marrow to produce more red blood cells (erythropoiesis). The increased erythropoiesis is the body's response to try to compensate for the decreased oxygen supply. Therefore, the correct answer is increased erythropoiesis.
21.
Which of the following is not true of monocytes?
Correct Answer
C. About same size as basopHils
Explanation
Monocytes are large white blood cells that have the ability to enter tissues and wander, become macrophages, phagocytize bacteria, and have a long lifespan. However, they are not about the same size as basophils. Basophils are smaller in size compared to monocytes.
22.
Which of the following would you expect to see in increased numbers in a peripheral blood sample after donating a unit of blood?
Correct Answer
C. Reticulocytes
Explanation
After donating a unit of blood, the number of reticulocytes would be expected to increase in a peripheral blood sample. Reticulocytes are immature red blood cells that are released by the bone marrow into the bloodstream in response to an increase in demand for oxygen-carrying cells. Therefore, after donating blood, the body would need to produce more red blood cells to replenish the loss, leading to an increase in reticulocyte count.
23.
People who suffer from hemophilia A fail to produce a functional Factor VIII; as a result
Correct Answer
C. They lack a functional intrinsic pathway
Explanation
People who suffer from hemophilia A lack a functional intrinsic pathway. Hemophilia A is a genetic disorder caused by a deficiency or absence of clotting factor VIII. The intrinsic pathway is one of the two pathways involved in the coagulation cascade. It is responsible for the formation of a blood clot in response to damage to the blood vessel walls. Without a functional intrinsic pathway, individuals with hemophilia A have impaired blood clotting ability, resulting in prolonged coagulation times.
24.
A digestive disorder that impairs a person's ability to absorb vitamin K will result in
Correct Answer
E. All of the above
Explanation
A digestive disorder that impairs a person's ability to absorb vitamin K will result in low levels of Factor X, low levels of prothrombin, low levels of thromboplastin, and prolonged bleeding. Vitamin K is essential for the production of these clotting factors, and without adequate levels of vitamin K, the body's ability to form blood clots is compromised. This can lead to prolonged bleeding and low levels of these clotting factors. Therefore, all of the above options are correct.
25.
Which of the following is true of eosinophils
Correct Answer
D. Constitute about 2 to 4 percent of WBCs
Explanation
Eosinophils are a type of white blood cell that are involved in the immune response, particularly in allergic reactions and parasitic infections. They have granules in their cytoplasm that stain with acid dyes, giving them a characteristic pink color. Eosinophils also have a bilobed nucleus, which means that their nucleus is divided into two lobes. In terms of their abundance, eosinophils typically make up about 2 to 4 percent of the total white blood cell count. Therefore, the statement "constitute about 2 to 4 percent of WBCs" is true for eosinophils.
26.
Identify the structure labeled "19" on the heart photo
Correct Answer
A. Pulmonary semilunar valve
Explanation
The structure labeled "19" on the heart photo is the pulmonary semilunar valve. This valve is located between the right ventricle and the pulmonary artery. It prevents the backflow of blood from the pulmonary artery into the right ventricle during ventricular relaxation.
27.
Identify the structure labeled "8
Correct Answer
A. Papillary muscles
Explanation
The structure labeled "8" is the papillary muscles. These muscles are found in the ventricles of the heart and attach to the chordae tendineae, which in turn attach to the cusps of the atrioventricular valves. The papillary muscles contract during ventricular systole to prevent the valves from prolapsing or inverting, ensuring proper blood flow through the heart.
28.
Identify the structure labeled "6
Correct Answer
D. Cusp of tricuspid valve
Explanation
The structure labeled "6" is the cusp of the tricuspid valve. The tricuspid valve is located between the right atrium and the right ventricle of the heart. It consists of three cusps or flaps that open and close to regulate the flow of blood between the two chambers. The cusp of the tricuspid valve helps to prevent the backflow of blood from the right ventricle into the right atrium during ventricular contraction.
29.
Which chamber receives oxygenated blood from the pulmonary circuit
Correct Answer
B. 16
Explanation
The correct answer is 16 because the chamber that receives oxygenated blood from the pulmonary circuit is the left atrium. The left atrium receives oxygenated blood from the lungs through the pulmonary veins and then pumps it into the left ventricle, which then pumps the oxygenated blood out to the rest of the body.
30.
Identify the structure labeled "21
Correct Answer
A. Ligamentum arteriosum
Explanation
The structure labeled "21" is the ligamentum arteriosum. The ligamentum arteriosum is a small fibrous band that connects the pulmonary trunk to the aortic arch in the heart. It is a remnant of a fetal blood vessel called the ductus arteriosus, which allows blood to bypass the lungs before birth. After birth, the ductus arteriosus closes and becomes the ligamentum arteriosum.
31.
Blood returning to the heart from the systemic circuit first enters the
Correct Answer
E. Right atrium
Explanation
Blood returning to the heart from the systemic circuit first enters the right atrium. The right atrium receives deoxygenated blood from the body through the superior and inferior vena cava. From the right atrium, the blood flows into the right ventricle through the tricuspid valve, and then it is pumped into the pulmonary circuit to be oxygenated in the lungs.
32.
The coronary sulcus is a groove that
Correct Answer
E. Marks the border between the atria and ventricles
Explanation
The coronary sulcus is a groove that marks the border between the atria and ventricles. This groove separates the upper chambers of the heart (atria) from the lower chambers (ventricles). It is an important landmark that helps to distinguish the different regions of the heart and plays a role in the circulation of blood.
33.
The cusps (leaflets) of atrioventricular valves attach directly to
Correct Answer
C. Chordae tendineae
Explanation
The cusps (leaflets) of atrioventricular valves attach directly to chordae tendineae. Chordae tendineae are thin, fibrous cords that connect the cusps of the AV valves to the papillary muscles in the ventricles. These tendons help to anchor the valves and prevent them from prolapsing or flipping into the atria when the ventricles contract.
34.
The visceral pericardium is the same as the
Correct Answer
B. Epicardium
Explanation
The visceral pericardium refers to the innermost layer of the pericardium, which is the protective sac surrounding the heart. It is also known as the epicardium. The epicardium is a thin, smooth layer that covers the surface of the heart and is composed of connective tissue and a layer of mesothelial cells. It provides protection to the heart and also helps in reducing friction between the heart and the surrounding structures. Therefore, the correct answer is epicardium.
35.
The right ventricle pumps blood to the
Correct Answer
A. Right and left lungs
Explanation
The right ventricle pumps blood to the right and left lungs. This is because the right ventricle receives deoxygenated blood from the right atrium and pumps it to the lungs through the pulmonary artery. In the lungs, the blood is oxygenated and then returned to the left atrium through the pulmonary veins. From the left atrium, the oxygenated blood is then pumped into the left ventricle and eventually to the rest of the body through the aorta.
36.
The right atrium receives blood from the
Correct Answer
D. A, B, and C
Explanation
The right atrium receives blood from the coronary sinus, inferior vena cava, and superior vena cava. The coronary sinus collects deoxygenated blood from the heart muscle itself, while the inferior vena cava brings deoxygenated blood from the lower body and the superior vena cava brings deoxygenated blood from the upper body. Therefore, all three options (A, B, and C) are correct.
37.
Blood flowing into the heart from the venae cavae flows next through the ________ valve.
Correct Answer
C. Tricuspid
Explanation
The correct answer is tricuspid. The tricuspid valve is located between the right atrium and right ventricle of the heart. It prevents the backflow of blood from the ventricle into the atrium during ventricular contraction.
38.
As blood leaves the right ventricle it passes through the ________ and then into the pulmonary trunk
Correct Answer
B. Conus arteriosus
Explanation
The correct answer is "conus arteriosus." The conus arteriosus is a funnel-shaped structure located at the base of the right ventricle. It acts as a pathway for blood to flow from the right ventricle into the pulmonary trunk, which then carries the blood to the lungs for oxygenation. The other options listed, such as the aorta, superior vena cava, inferior vena cava, and pulmonary veins, are not correct because they do not describe the structure through which blood passes before entering the pulmonary trunk.
39.
The pulmonary semilunar valve prevents backward flow into the
Correct Answer
C. Right ventricle
Explanation
The pulmonary semilunar valve is located between the right ventricle and the pulmonary trunk. Its main function is to prevent the backward flow of blood from the pulmonary trunk into the right ventricle. This ensures that oxygenated blood flows from the right ventricle into the pulmonary trunk and then to the lungs for oxygenation. Therefore, the correct answer is the right ventricle.
40.
The bicuspid or mitral valve is located
Correct Answer
E. Between the left atrium and left ventricle
Explanation
The correct answer is "between the left atrium and left ventricle." The bicuspid or mitral valve is located between the left atrium and left ventricle of the heart. It is responsible for preventing the backflow of blood from the left ventricle into the left atrium during ventricular contraction.
41.
The ________ valve prevents backward flow into the left atrium
Correct Answer
B. Bicuspid
Explanation
The bicuspid valve, also known as the mitral valve, is located between the left atrium and the left ventricle of the heart. Its main function is to prevent the backward flow of blood into the left atrium when the left ventricle contracts and pumps blood out to the rest of the body.
42.
The function of the atrium is to
Correct Answer
E. Both A and D
Explanation
The atrium has two main functions: to collect blood and to pump blood to the ventricle. It receives blood from either the body (in the case of the right atrium) or the lungs (in the case of the left atrium) and then contracts to push the blood into the ventricle. Therefore, option "both A and D" is correct as it includes both of these functions.
43.
Compared to the right ventricle, the left ventricle has all the following characteristics, except that it
Correct Answer
C. Pumps a greater volume
Explanation
The left ventricle pumps a greater volume of blood compared to the right ventricle. This is because the left ventricle is responsible for pumping oxygenated blood to the rest of the body, while the right ventricle pumps deoxygenated blood to the lungs. The left ventricle has a thicker wall, round cross section, and produces more pressure when it contracts, all of which contribute to its ability to pump a greater volume of blood.
44.
The pulmonary arteries carry blood to the
Correct Answer
A. Lungs
Explanation
The pulmonary arteries carry blood to the lungs.
45.
The pulmonary veins carry blood to the
Correct Answer
E. Heart
Explanation
The pulmonary veins carry blood from the lungs back to the heart.
46.
Blood is supplied to the myocardium by
Correct Answer
C. The coronary arteries
Explanation
The myocardium, which is the muscular tissue of the heart, receives its blood supply from the coronary arteries. These arteries branch off from the aorta and provide oxygenated blood to the heart muscle. The coronary arteries ensure that the myocardium receives the necessary nutrients and oxygen to function properly. Therefore, the correct answer is the coronary arteries.
47.
The marginal branch and posterior interventricular branch are branches of the
Correct Answer
C. Right coronary artery
Explanation
The marginal branch and posterior interventricular branch are both branches of the right coronary artery. The right coronary artery is one of the main arteries that supplies blood to the heart. It originates from the aorta and travels along the surface of the heart, giving off various branches along the way. The marginal branch supplies blood to the right ventricle, while the posterior interventricular branch supplies blood to the posterior part of the interventricular septum.
48.
The heart is innervated by ________ nerves
Correct Answer
D. Both parasympathetic and sympathetic
Explanation
The heart is innervated by both parasympathetic and sympathetic nerves. The parasympathetic nervous system slows down the heart rate and reduces the force of contractions, while the sympathetic nervous system increases the heart rate and enhances the force of contractions. These two systems work together to maintain the balance and regulation of the heart's activity.
49.
The long plateau phase of the cardiac muscle action potential is due to
Correct Answer
A. Calcium channels remaining open
Explanation
The long plateau phase of the cardiac muscle action potential is due to calcium channels remaining open. This allows an influx of calcium ions into the cell, which prolongs the depolarization phase and delays repolarization. This is important for the proper functioning of the heart, as it allows for sufficient time for the heart to contract and pump blood effectively.
50.
The normal pacemaker of the heart is located in the
Correct Answer
D. Sinoatrial node
Explanation
The sinoatrial node is the normal pacemaker of the heart. It is located in the wall of the right atrium. It generates electrical impulses that regulate the heart's rhythm and initiate the contraction of the atria. These impulses then travel through the atrioventricular node and the Purkinje fibers to stimulate the contraction of the ventricles. The sinoatrial node is responsible for initiating each heartbeat and ensuring that the heart beats at a regular and coordinated pace.