Podcast Beta
Questions and Answers
What is the primary function of erythrocytes in the blood?
Which of the following accurately describes the physical characteristics of blood?
Which component of blood plasma is primarily responsible for regulating osmotic pressure?
What is the composition of blood plasma?
Signup and view all the answers
Which of these statements correctly describes the formed elements in blood?
Signup and view all the answers
Which type of protein in the blood plasma helps protect the body from antigens?
Signup and view all the answers
What anatomical feature characterizes erythrocytes?
Signup and view all the answers
What is the correct pH range that blood must maintain?
Signup and view all the answers
What is the primary function of hemoglobin in the blood?
Signup and view all the answers
What is leukocytosis and what does it generally indicate?
Signup and view all the answers
Which type of leukocyte is characterized by the presence of granules that can be stained?
Signup and view all the answers
Which granulocyte is primarily involved in the phagocytosis of pathogens at infection sites?
Signup and view all the answers
What are agranulocytes and which types fall under this category?
Signup and view all the answers
Basophils are known for containing granules that release which substance that initiates inflammation?
Signup and view all the answers
What is the normal range of leukocyte levels in the blood?
Signup and view all the answers
What is the primary role of eosinophils in the immune response?
Signup and view all the answers
What effect does serotonin have during vascular spasms?
Signup and view all the answers
Which component is pivotal for triggering the clotting cascade?
Signup and view all the answers
What is the primary role of thrombin in the coagulation process?
Signup and view all the answers
What occurs after a blood clot has formed?
Signup and view all the answers
What condition is characterized by a deficiency in platelets?
Signup and view all the answers
How long does it typically take for blood to clot after an injury?
Signup and view all the answers
What is a thrombus?
Signup and view all the answers
What can occur if a thrombus breaks away and travels in the bloodstream?
Signup and view all the answers
What is the primary role of lymphocytes in the body?
Signup and view all the answers
Which of the following statements about monocytes is correct?
Signup and view all the answers
What is the normal platelet count in the human body?
Signup and view all the answers
What process occurs in red bone marrow related to blood cell formation?
Signup and view all the answers
Which hormone controls the production of erythrocytes?
Signup and view all the answers
What is the main purpose of hemostasis in the body?
Signup and view all the answers
What happens to erythrocytes when they can no longer function?
Signup and view all the answers
What initially causes platelets to become sticky during hemostasis?
Signup and view all the answers
What primarily causes the most vigorous transfusion reactions in blood transfusions?
Signup and view all the answers
What determines whether blood types A, B, AB, or O are present?
Signup and view all the answers
What is the risk associated with a mismatch between an Rh– mother and an Rh+ baby?
Signup and view all the answers
In which scenario is hemolytic disease of the newborn most likely to occur?
Signup and view all the answers
Which blood group is characterized by the presence of both A and B antigens?
Signup and view all the answers
What is the main purpose of typing blood using antibodies?
Signup and view all the answers
What defines an Rh+ blood type?
Signup and view all the answers
Which statement is true regarding the Rh blood group system?
Signup and view all the answers
Study Notes
Introduction
- Blood is the only fluid tissue in the human body
- It is classified as a connective tissue
- Blood contains living cells (formed elements) and a non-living matrix (plasma)
Physical Characteristics of Blood
- Oxygen-rich blood is scarlet red; oxygen-poor blood is dull red
- The pH of blood must remain between 7.35 and 7.45
- The temperature of blood is slightly higher than body temperature
Blood Plasma
- Blood plasma is approximately 90% water
- Includes dissolved substances such as nutrients, salts, respiratory gases, hormones, proteins, and waste products
Plasma Proteins
- Albumin helps to regulate osmotic pressure
- Clotting proteins help to stem blood loss when a blood vessel is injured
- Antibodies help protect the body from antigens
Formed Elements of Blood
- Erythrocytes (red blood cells) are responsible for carrying oxygen
- Leukocytes (white blood cells) are crucial in the body's defense against disease
- Platelets are cell fragments needed for the clotting process
Erythrocytes (Red blood Cells)
- Erythrocytes are biconcave discs
- Erythrocytes contain very little organelles and are anucleate (lack a nucleus)
- They are essentially bags of hemoglobin
- Erythrocytes outnumber white blood cells 1000:1
Hemoglobin
- Hemoglobin is an iron-containing protein
- Each hemoglobin molecule can bind to four oxygen molecules
- Each erythrocyte contains 250 million hemoglobin molecules
Leukocytes (White Blood Cells)
- Leukocytes are complete cells with a nucleus and organelles
- Leukocytes can move into and out of blood vessels (diapedesis)
- They can move by ameboid motion
- They respond to damaged tissue chemicals
Leukocyte Levels in Blood
- Normal leukocyte levels are between 4,000 and 11,000 cells per millimeter
- Leukocytosis is an abnormal increase over 11,000 cells/ml and may indicate an infection
- Leukopenia is an abnormally low leukocyte level, commonly caused by drugs
Types of Leukocytes: Granulocytes
- Granulocytes contain granules in their cytoplasm that can be stained
- Neutrophils have a multilobed nucleus, contain fine granules, and act as phagocytes at infection sites
- Eosinophils have large brick-red cytoplasmic granules and respond to allergies and parasitic worms
- Basophils contain histamine-containing granules and initiate inflammation
Types of Leukocytes: Agranulocytes
- Agranulocytes lack visible cytoplasmic granules
- Lymphocytes have a nucleus that fills most of the cell and play an important role in the immune response
- Monocytes are the largest white blood cells and function as macrophages - important in fighting chronic infection
Platelets
- Platelets are derived from ruptured megakaryocytes (multinucleate cells).
- Platelets are required for blood clotting
- Normal platelet count is 300,000 per mm3
Hematopoiesis
- Hematopoiesis is blood cell formation
- Occurs in red bone marrow
- All blood cells originate from a common stem cell (hemocytoblast)
- Hemocytoblasts differentiate into lymphoid stem cells (which produce lymphocytes) and myeloid stem cells (which produce other blood cells)
Fate of Erythrocytes
- Erythrocytes are unable to divide, grow or synthesize proteins
- Erythrocytes wear out in 100-120 days
- Worn-out erythrocytes are eliminated by phagocytes in the spleen or liver
- Lost cells are replaced by division of hemocytoblasts
Control of Erythrocyte Production
- Rate is controlled by erythropoietin (a hormone)
- Kidneys produce most erythropoietin, triggered by reduced oxygen levels in the blood
- Homeostasis is maintained by negative feedback from blood oxygen levels
Hemostasis
- Hemostasis is the stoppage of blood flow
- Occurs after blood vessel breaks
- Hemostasis involves three phases: platelet plug formation, vascular spasms, and coagulation
Platelet Plug Formation
- Collagen fibers are exposed when blood vessels break
- Platelets become sticky and cling to fibers
- Anchored platelets release chemicals to attract more platelets
- Platelets pile up to form a platelet plug
Vascular Spasms
- Anchored platelets release serotonin
- Serotonin causes blood vessel muscles to spasm
- Spasms narrow blood vessels, decreasing blood loss
Coagulation
- Injured tissues release thromboplastin
- PF3 (phospholipid) interacts with thromboplastin, blood protein clotting factors, and calcium ions to trigger a clotting cascade
- Prothrombin activator converts prothrombin to thrombin (an enzyme)
- Thrombin joins fibrinogen proteins to form fibrin (hair-like protein)
- Fibrin forms a meshwork that forms the basis for a clot
Blood Clotting
- Blood usually clots within 3-6 minutes
- Blood clot remains as endothelium regenerates
- Clot is broken down after tissue repair
Undesirable Clotting
- Thrombus: a clot in an unbroken blood vessel; can be deadly in areas like the heart
- Embolus: a thrombus that breaks away and floats freely; can clog vessels in critical areas (e.g., brain)
Bleeding Disorders
- Thrombocytopenia: platelet deficiency; even normal movements can cause bleeding from small blood vessels
- Hemophilia: hereditary bleeding disorder; normal clotting factors are missing
Blood Groups and Transfusions
- Large blood loss can have serious consequences
- Losing 15-30% of blood can cause weakness
- Losing over 30% of blood can cause shock, which can be fatal
- Transfusions are the only way to replace blood quickly
- Transfused blood must be of the same blood group
Human Blood Groups
- Blood contains genetically determined proteins (antigens)
- Foreign proteins can be attacked by the immune system
- Blood is "typed" by using antibodies that cause agglutination (clumping) of blood with certain antigens
Human Blood Groups
- Over 30 common red blood cell antigens exist
- The most vigorous transfusion reactions are caused by ABO and Rh blood group antigens
ABO Blood Groups
- ABO blood groups are based on the presence or absence of two antigens: Type A and Type B
- Type O blood lacks both A and B antigens
- Type AB blood contains both A and B antigens
Rh Blood Groups
- Rh blood groups are named after one of eight Rh antigens (agglutinogen D)
- Most Americans are Rh+
- Mixing Rh+ blood with Rh- blood can cause problems
Rh Dangers During Pregnancy
- Rh- mother carrying an Rh+ baby can cause problems for the unborn child
- The first pregnancy usually proceeds without problems
- The mother's immune system is sensitized after the first pregnancy
- During a second pregnancy, mother's antibodies attack the Rh+ blood (hemolytic disease of the newborn)
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
This quiz covers the essential characteristics of blood, including its classification as a connective tissue and its physical properties. It also delves into the components of blood plasma, various plasma proteins, and the formed elements such as erythrocytes and leukocytes. Test your understanding of these vital concepts!
