Description:T cells are a type of white blood cell that play a central role in the immune response. They are involved in recognizing and attacking foreign pathogens, such as bacteria and viruses, as well as abnormal cells, such as cancer cells. Helper T cells, also known as CD4+ T cells, assist in the immune response by activating other immune cells and coordinating the overall immune response. They secrete chemical signals called cytokines that help regulate and enhance the immune system's response to an infection. Cytotoxic T cells, also known as CD8+ T cells, are responsible for directly attacking and killing infected cells or abnormal cells. They recognize specific antigens displayed on the surface of target cells and release toxic substances that induce cell death. B cells, on the other hand, are another type of white blood cell involved in the immune response, but they are primarily responsible for producing antibodies. Monocytes and macrophages are also types of white blood cells, but they have different functions, such as engulfing and digesting pathogens and cellular debris.

Description:Hemoglobin (Hb) is composed of four globin chains (two alpha chains and two beta chains) in each Hb molecule. So, statement a is correct. Each Hb molecule can bind to and carry up to four oxygen molecules simultaneously. Therefore, statement b is correct. Oxygen is transported in the bloodstream by binding to hemoglobin, forming a complex called oxyhemoglobin. Hence, statement c is also correct.

Description:The oncotic pressure of plasma is primarily due to the presence of albumin, which is a protein found in the blood. Albumin is the most abundant protein in plasma and contributes significantly to the osmotic pressure, also known as oncotic pressure. This pressure helps to retain water within the blood vessels and prevent it from leaking out into the surrounding tissues.

Description:Heme is a component of hemoglobin, which is found in red blood cells and is responsible for carrying oxygen throughout the body. When red blood cells reach the end of their lifespan, they are broken down in a process called hemolysis. During hemolysis, heme is released from hemoglobin. The conversion of heme to bilirubin occurs primarily in the liver. Once heme is released, it is taken up by liver cells where it undergoes a series of enzymatic reactions to produce bilirubin. Bilirubin is a yellow pigment that is further processed in the liver before being excreted into the bile. The liver plays a crucial role in the metabolism of bilirubin. It conjugates bilirubin with glucuronic acid, forming bilirubin glucuronides, which are water-soluble and can be excreted in the bile. From the liver, bilirubin travels through the bile ducts and enters the small intestine, where it undergoes further modifications and eventually leaves the body in the feces. While the spleen is involved in the removal of old red blood cells, it does not play a significant role in the conversion of heme to bilirubin. The kidneys primarily function in filtering waste products from the blood and regulating water and electrolyte balance, but they are not directly involved in the conversion of heme to bilirubin. Similarly, while the bone marrow is responsible for the production of red blood cells, it is not involved in the conversion of heme to bilirubin.

Description:The absence of lymph nodes is characteristic of all the options provided except for the brain. Lymph nodes are present in various parts of the body and play a crucial role in the immune system. Lymph nodes can be found throughout the body, including the neck, armpits, groin, and other regions. They are responsible for filtering lymph fluid, removing waste, and fighting off infections. However, lymph nodes are not found in the brain. Instead, the brain has a separate system called the glymphatic system, which helps clear waste and toxins from the central nervous system.

Description:The liver is the exception in the list provided because it does have lymphatics. Lymphatics are small vessels that are part of the lymphatic system, which is responsible for draining excess fluid, waste products, and immune cells from the tissues and returning them to the bloodstream. The liver contains lymphatic vessels, known as hepatic lymphatics, which help in the drainage of lymph fluid from the liver. On the other hand, the brain, internal ear, and cornea (not "comea") are examples of organs or structures that lack lymphatics. These tissues have a relatively low concentration of lymphatic vessels, and their lymphatic drainage is limited. However, it is important to note that recent research has suggested the presence of a lymphatic system within the central nervous system, including the brain, which was previously thought to be devoid of lymphatics. This discovery has provided new insights into the immune response and waste clearance in the brain.

Description:Monocytes are a type of white blood cell that plays a role in the immune system's defense against pathogens. In a peripheral blood smear, monocytes typically exhibit a horse-shoe shaped or kidney-shaped nucleus and have abundant cytoplasm surrounding the nucleus. This distinctive morphology helps in their identification. Neutrophils, lymphocytes, and eosinophils have different nuclear and cytoplasmic characteristics.

Description:Infectious mononucleosis invades B-cells.

Description:A person with AB positive blood type is considered a universal recipient because they can receive blood from individuals with any blood type. This is because the AB blood type has both A and B antigens on the surface of red blood cells and has the Rh factor (positive). Since they have both A and B antigens, their immune system does not recognize A or B blood as foreign, and the Rh factor does not cause an immune response. On the other hand, individuals with blood types A negative, O negative, and B positive have specific antigens on their red blood cells that can cause immune reactions in the recipient if they receive blood from incompatible blood types. To summarize, AB positive individuals can receive blood from any blood type without the risk of immediate immune reactions, making them the universal recipients.

Description:The universal donor blood group is O negative (O-). People with this blood type can donate their blood to individuals with any other blood type, making it compatible with all blood types. This is because O negative blood lacks both A and B antigens on the surface of red blood cells and does not contain the Rh factor. Therefore, it is considered the safest option for emergency situations when the recipient's blood type is unknown or in cases where there is a shortage of compatible blood.

Description:he ABO locus, which determines the ABO blood group system, is located on the long arm (q arm) of chromosome 9.

Description:e. All of the techniques mentioned—immunochromatographic cartilage, card agglutination, and gel card technique—are used for blood grouping. Let's briefly describe each technique: Immunochromatographic Cartilage: This technique utilizes a test strip containing specific antibodies against the blood group antigens. When a blood sample is added to the strip, it reacts with the antibodies, leading to the formation of visible lines or colors, indicating the blood group. Card Agglutination: In this method, a blood sample is mixed with specific antibodies on a card. If the antigens corresponding to those antibodies are present on the red blood cells, agglutination (clumping) occurs, indicating the blood group. Gel Card Technique: This technique uses gel particles coated with antibodies specific to different blood group antigens. The blood sample is mixed with these gel particles, and if there is a reaction between the antibodies and the antigens present in the blood, the red blood cells will form a clump or aggregate. The formation or absence of agglutination determines the blood group. All of these techniques are commonly used in blood banks and laboratories for accurate blood typing and cross-matching.

Description:Prolonged stays in space, such as in microgravity environments, can have various effects on the human body. These effects are collectively referred to as spaceflight-associated neuro-ocular syndrome (SANS) or space adaptation syndrome. While many changes occur in the body during spaceflight, one of the primary effects on the blood is a decrease in blood volume (a). In microgravity, the body no longer needs to fight against gravity to pump blood to the lower extremities, resulting in a redistribution of fluids from the lower body to the upper body. This fluid shift leads to a decrease in blood volume. Additionally, prolonged stays in space can lead to decreased muscle strength (d). The absence of gravity in space removes the constant resistance on muscles and bones that is experienced on Earth. As a result, astronauts in space experience muscle atrophy and a decrease in muscle strength. The incorrect answer is b. Decreased hematocrit. Hematocrit refers to the percentage of red blood cells in the total blood volume. During prolonged stays in space, astronauts typically experience an increase in hematocrit rather than a decrease. The increase in hematocrit is thought to be a compensatory response to the decrease in blood volume. With a reduced blood volume, the body tries to maintain adequate oxygen-carrying capacity by increasing the concentration of red blood cells. It's worth noting that while prolonged stays in space can lead to decreased cardiac output during the initial period of space adaptation, this effect is usually transient. Over time, the body adjusts to the microgravity environment, and cardiac output returns to near-normal levels or may even increase.

Description:For a complete blood count (CBC), blood is typically collected in an EDTA (ethylenediaminetetraacetic acid) vial. EDTA is an anticoagulant that prevents the blood from clotting by binding calcium ions, which are necessary for the coagulation process. This allows the blood sample to remain in a liquid state and preserves the integrity of the cells for accurate testing. The other options listed (b. Plan vial, c. Citrate vial, and d. Chloride vial) are not commonly used for CBC testing. Plan vials, citrate vials, and chloride vials may be used for other specific tests or analyses, such as coagulation studies (citrate vials) or electrolyte measurements (chloride vials), but not for a standard CBC.

Description:Potassium oxalate and sodium fluoride are commonly used as an anticoagulant additive in blood sugar vials. Potassium oxalate acts as an anticoagulant by inhibiting the clotting process, while sodium fluoride helps preserve glucose levels by inhibiting the enzyme that breaks down glucose in the blood. This combination of additives helps prevent blood clotting and preserves the integrity of glucose levels in the blood sample for accurate testing.

Description:EDTA (ethylene diamine tetraacetic acid) is an anticoagulant commonly used for hematological tests. It works by binding calcium ions, which are essential for blood clotting, thereby preventing the blood from clotting. EDTA is especially effective for tests that require a complete blood count (CBC) and differential cell count. It helps preserve the integrity of blood cells and allows for accurate analysis of various blood parameters. Sodium fluoride is primarily used as a preservative for glucose testing and is not typically used as an anticoagulant for hematological tests. Heparin and Clexane (a brand name for enoxaparin) are anticoagulants used for other purposes, such as preventing blood clots in patients with certain medical conditions, and are not commonly used for routine hematological testing.

Description:Stain: • Wright’s stain • Supravital stain Blood cell: • RBC, WBC (differential count) • Reticulocyte (stain used New methylene blue or Brilliant cresyl blue)

Description:To diagnose anemia, healthcare professionals typically use a combination of methods, including: a) Hematogram and hematocrit: These tests involve analyzing a blood sample to measure the levels of different components of the blood, such as red blood cells, hemoglobin, and hematocrit. Abnormal levels can indicate the presence of anemia. b) History and examination: Gathering information about the patient's medical history, symptoms, and conducting a physical examination can provide important clues to help diagnose anemia. This includes asking about symptoms such as fatigue, weakness, shortness of breath, and examining physical signs like pale skin or rapid heart rate. c) Peripheral blood smear examination: This test involves examining a sample of blood under a microscope to evaluate the shape, size, and characteristics of the red blood cells. Abnormalities in the appearance of the red blood cells can provide additional information about the type and cause of anemia. Therefore, all of these methods are commonly used together to diagnose anemia and determine its underlying cause

Description:The test used to find out Vitamin B12 deficiency is the Schilling test. The Schilling test is a diagnostic test that measures the absorption of radioactive vitamin B12 in the gastrointestinal tract. It helps to determine if there is a problem with the absorption of vitamin B12 from the diet or if there is an underlying condition causing the deficiency. This test is often used when other blood tests indicate a possible vitamin B12 deficiency.

Description:The total serum protein range is typically 6.0 to 8.2 g/dl.

Description:The target International Normalized Ratio (INR) value for a patient with a mechanical prosthetic heart valve is typically in the range of 2.5-3.5. This range is considered optimal for most patients with mechanical heart valves to prevent blood clots while minimizing the risk of bleeding complications. However, it's important to note that the specific target INR range may vary depending on the individual patient's condition and the type of mechanical heart valve they have. It is always best to consult with a healthcare professional for personalized advice and monitoring of the INR levels

Description:Multigated acquisition (MUGA) scanning is a nuclear medicine imaging modality that aids providers evaluate the heart's structural and dynamic properties. They are imaging modalities with many names, including radionucleotide ventriculography (RVG) and gated equilibrium radionucleotide angiography (ERNA).

Description:Capillary refill time is normally 1-3 seconds. Capillary refill time is a simple test used to assess peripheral circulation and tissue perfusion. It measures the time it takes for color to return to a compressed nail bed after pressure is released. In a healthy individual, the color should return within 1-3 seconds, indicating good peripheral circulation. If the refill time is prolonged (more than 3 seconds), it may indicate poor circulation or other underlying medical conditions.

Description:Serological tests are not a type of in-vivo test. In-vivo tests refer to tests performed inside a living organism, whereas serological tests are conducted outside the body in a laboratory setting. Serological tests are used for the identification and quantification of antigens and antibodies, and environmental factors like pH, salt concentration, and temperature can indeed interfere with these tests. Agglutination reaction and precipitation reactions are examples of serological tests.

Description:Direct agglutination tests can be used to detect the presence of antibodies in serum. They utilize known antigens that are present on coated cells. These tests can be used for various purposes, including the diagnosis of diseases such as leishmaniasis and typhoid.