Fundamentals Of Blood
What are the 3 functions of the blood?
- Transport: Oxygen, Nutrients, waste, and hormones
- Regulation: Body Temp, pH, and fluid volume
- Protection: blood loss and infection
Which layer of the blood contains the majority of leukocytes and platelets?
The buffy coat
What are the four main blood groups?
A, B, AB, and O
Which hormone primarily regulates erythropoiesis and where is it produced?
Erythropoietin (EPO), kidneys
What is anemia, and how is it classified?
Anemia is a symptom where the blood has a reduced capacity to carry oxygen; it is classified based on causes such as blood loss, insufficient RBC production, or RBC destruction.
What are the formed elements in blood and their percentages in the blood?
Erythrocytes(45%), leukocytes(<1%), and platelets
Explain what is hematocrit?
Hematocrit is the percentage of RBCs in blood
What determines an individual’s blood type?
The presence or absence of specific antigens (agglutinogens) on the surface of RBCs.
What triggers the production of erythropoietin?
Low oxygen levels in the blood
What is sickle-cell anemia?
A genetic disorder where hemoglobin is abnormal, causing RBCs to become misshapen and rupture easily.
What percentage of blood is plasma, and what does it primarily consist of?
Plasma makes up about 55% of blood and is composed primarily of water (90%).
What are the three major differences between erythrocytes and leucocytes?
Who is considered a universal donor and a universal recipient?
Universal donor: Type O-. Universal recipient: Type AB+.
What are the consequences of having too many erythrocytes?
Polycythemia, which can lead to increased blood viscosity and the risk of thrombosis.
What is polycythemia and the risk associated?
- Abnormal excess of RBCs(hematocrit as high as 80%)
- The risk includes increased blood viscosity, which can lead to stroke, heart attack, or thrombosis.
Dehydration causes which element in the blood to decrease?
Plasma
What is the primary role of hemoglobin within erythrocytes, and how does it contribute to the transport of oxygen and carbon dioxide in the blood?
Hemoglobin in erythrocytes primarily binds to oxygen in the lungs and releases it in tissues, facilitating oxygen transport throughout the body. It also binds to carbon dioxide in tissues, aiding in its transport back to the lungs for exhalation. This dual function of hemoglobin is essential for maintaining cellular respiration and overall metabolic balance.
What happens during a transfusion reaction?
The recipient’s antibodies attack the donor’s RBCs, causing them to clump, rupture, and potentially block blood vessels.
Describe what hematopoiesis is and how it works
- blood cell formation in red bone marrow
- Red bone marrow---> Hematopoietic stem cells (hemocytoblasts)---> Hormones and growth factors push cells toward specific pathways of blood cell
development----> RBC's, WBC's, and Platelets
Describe the condition of thrombocytopenia.
Thrombocytopenia is a deficiency in platelets, leading to impaired clot formation and an increased risk of bleeding.
Describe the composition of hemoglobin and its primary function
Hemoglobin is composed of heme and globin chains, with each heme group containing an iron atom that binds oxygen; its primary function is oxygen transport.
How does the structural adaptation of erythrocytes enhance their function in oxygen transport, and what are the consequences if these adaptations are compromised?
Erythrocytes have a biconcave shape that increases their surface area for efficient gas exchange and allows them to deform as they pass through narrow capillaries. They lack a nucleus and mitochondria, maximizing space for hemoglobin, which binds and transports oxygen. If these structural adaptations are compromised, as seen in conditions like sickle-cell anemia, oxygen delivery is impaired, leading to tissue hypoxia, pain, and potential organ damage.
What is the significance of the Rh factor in blood typing?
It determines whether blood is Rh+ or Rh-, which is crucial for blood transfusions and pregnancy.
What is hemostasis and the 3 steps involved?
Step 1: Vascular spasm: Vessel responds to injury with vasoconstriction: most effective in smaller blood vessels
Step 2: Platelet plug formation: Platelets ~sticky and spiky~ stick to collagen fibers exposed when the vessel is damaged, positive feedback
Step 3: Coagulation(blood clotting): reinforces platelet plug with fibrin threads, blood becomes gel rather than liquid
In response to significant blood loss, what mechanisms does the cardiovascular system employ to minimize the impact, and how do these mechanisms help maintain homeostasis?
The cardiovascular system minimizes the effects of blood loss through vasoconstriction, which reduces the volume of blood vessels, and by increasing the production of red blood cells (RBCs) to restore blood volume. These mechanisms help maintain blood pressure and oxygen delivery to vital organs, preventing shock and ensuring continued cellular function until normal blood volume can be restored.