Chapter 1–7: Blood, Cells, and Hematopoiesis Vocabulary

Attendance, Access, and Course Structure

• Attendance incentives and video access
  • Students who come to class and complete the attendance check unlock the videos.
  • If you miss class, the videos do not unlock because some students don’t attend.
• Class identity and privacy
  • The instructor uses your class to reference your questions and knows who you are.
  • For anything related to grades, information is only released via Canvas (the secure platform).
• Grades and communication channels
  • For grades, Canvas is the easiest and fastest way to receive information.
• Support resources available
  • Free tutoring in the library; tutoring services in the Learning Center above the library.
  • Models used in course are available in the Learning Center for practice.
• Textbook and resources mentioned
  • Textbook access via links; "Invisible Body" is referenced as a three-dimensional anatomy resource.
  • Links will lead directly into the textbook resources.
• Course layout and weekly structure
  • Each week has modules with directions and resources.
  • Directions explain what’s due and what is required (attachments not yet fixed).
• Attendance policy details
  • If you miss class, you do not unlock the lecture.
  • Policy: one free absence per semester with prior communication and notification to the instructor.
• Instructor background and teaching approach
  • Dr. (instructor) has healthcare background: 10 years in nursing, clinical experience.
  • Preference for anatomy; enjoys discussing healthcare topics and may go on tangents.
  • Encourages questions during lectures; will not yell and will help you understand.
• Schedule and upcoming topics
  • Today’s topic: Blood and the cardiovascular system; first five weeks focus on heart, blood, cardiovascular topics.
  • The course will later dissect tissues and structures at year-end; course calendar will be posted.
  • First test in week five; test content is heart and cardiovascular topics.
• Assessments and calendar transparency
  • Course calendar lists exam and lab exam coverage by chapters and labs, so students know content beforehand.
• Study guidance and exam preparation
  • The instructor may highlight particularly important topics and occasionally note when a test question mirrors a specific point word-for-word.
  • You will be allowed to use handwritten notes for 10–15 minutes on tests; notes must be handwritten (any writing style allowed).
  • Rationale for handwritten notes: writing aids retention.
• Note-taking scope and materials for exams
  • Three major content blocks: Heart/Cardiovascular; Labeled modules include Heart, Lungs/Respiratory, Urinary, and Reproductive systems.
  • No extra questions beyond the stated content after a given lecture, but the lecture and lab content are integrated.
• Lab structure and class pairing
  • Two-class format: two lectures on Mon/Wed and a lab on designated days.
  • After lecture, students in the Wednesday lab cohort move to lab; those in the other cohort may have lab on a different day.
• Class identification and cohort examples
  • Example cohorts referenced: class numbers such as 10734 with Wednesday lab; another likely class number around 101414 relates to Immunology.
• Practical context for blood topics
  • Immunology focuses on blood, cancer, and conditions like hematuria (blood in urine).
• Terminology introduced in today’s session
  • Hematology terms introduced: hemoglobin, heme, iron, plasma, formed elements, erythrocytes, leukocytes, platelets.
• Quick clinical scenarios mentioned
  • Hematuria indicates blood in urine.
  • PC/UD labs and centrifuges used in hospital settings (e.g., jail lab example) for separating blood components.

Core concepts: Blood components and their roles

• Blood is composed of plasma (fluid) and formed elements (cells and cell fragments)
  • Plasma carries nutrients, wastes, and proteins; serves as the liquid component of blood.
  • Formed elements include erythrocytes (red blood cells), leukocytes (white blood cells), and platelets.
• Erythrocytes (RBCs)
  • Primary job: transport oxygen from lungs to tissues and return a small amount of carbon dioxide.
  • Oxygen carrier: hemoglobin with heme iron that binds O₂; iron is essential for binding capability.
  • RBCs lack organelles in mature form: they have no nucleus, no mitochondria, and no DNA in mature cells.
  • RBCs are the heaviest elements in centrifuged blood and typically settle at the bottom of tubes.
  • Normal RBC-related percentages (hematocrit):
  • Overall range: ext{RBC hematocrit} ext{ ~ } 37 ext{–}52 ext{%}
  • In women: 37 ext{–}48 ext{%.}
  • Hemoglobin binding and oxygen transport efficiency depend on iron availability.
  • Membrane stability: cytoskeletal proteins (spectrin and actin) give durability and elasticity to RBC membranes.
  • Hemoglobin structure: four globin chains bound to four heme groups; each heme contains iron and binds one O₂ molecule.
  • If all binding sites are occupied by oxygen, the RBCs are at 100% saturation; if some sites are unbound, saturation is less (e.g., 75%, 85%).
• Leukocytes (WBCs)
  • Immune cells with multiple specialized roles; increase in infection often leads to higher WBC counts.
  • Subtypes mentioned: neutrophils, eosinophils, basophils (collectively called “the fills” in lecturing shorthand); monocytes; lymphocytes.
  • Neutrophils, eosinophils, basophils are early responders to infection or inflammation.
  • Monocytes and lymphocytes are myeloid and lymphoid-derived lines, respectively; lymphocytes include T cells and B cells (lymphoid origin).
  • WBCs originate primarily in bone marrow (myeloid lineage) except for lymphocytes, which are produced in lymphoid tissues.
  • A high WBC count can indicate infection; a low WBC count may indicate a compromised immune system (e.g., AIDS, cancer) due to reduced production.
• Platelets
  • Fragments of bone marrow-derived cells; essential for blood clotting and hemostasis.
  • Platelets are part of the formed elements; involved in stopping bleeding.
• Plasma and plasma proteins
  • Albumin: the most abundant plasma protein and the smallest in size; major contributor to blood viscosity and oncotic/osmotic pressure; helps maintain intravascular volume and prevents edema.
  • Globulins: antibodies; immune proteins.
  • Fibrinogen: converts to fibrin during clot formation; critical in coagulation.
  • Liver-produced proteins: the liver synthesizes most plasma proteins, including albumin, globulins, and fibrinogen.
  • Other plasma constituents: nitrogenous compounds (e.g., amino acids, metabolites), drugs, carbon dioxide; these are carried in plasma and are slowly cleared by the kidneys.
• Blood viscosity and osmolarity
  • Viscosity: resistance to flow; higher viscosity generally means thicker blood.
  • Osmolarity: amount of fluid (water) content in blood; kidneys regulate osmolarity to maintain homeostasis.
  • Excess water in blood increases blood volume and can raise pressure if vessel size is unchanged; too little water lowers volume and pressure.
• Blood volume regulation and hypoxemia/hypoxia
  • Hypoxemia: low oxygen in blood; hypoxia refers to insufficient oxygen delivery to tissues.
  • Negative feedback mechanisms: when oxygen is low, the body can respond by increasing red blood cell production (erythropoiesis) to improve oxygen transport.
  • Altitude adaptation: chronic hypoxia at high altitude may trigger increased red blood cell production; however, excessive RBC production is not helpful if there is insufficient oxygen in the environment.
  • Chronic hypoxia conditions (e.g., COPD) can lead to higher RBC counts as a compensatory mechanism.
• Erythropoiesis and hematopoiesis
  • Hematopoiesis: the process of producing blood cells; etymology: poiesis means "to make".
  • Erythropoiesis: production of red blood cells.
  • Lymphoid hematopoiesis: production of lymphoid cells in lymphatic organs; hematopoietic tissues like the spleen contribute to immune cell lineages.
  • Myeloid hematopoiesis: production of blood cells in the bone marrow (myeloid lineage includes many white cells and red blood cells).
  • Red blood cells are produced almost exclusively in bone marrow (red bone marrow in adults).
  • The spleen participates in hematopoiesis for immune cells but does not produce erythrocytes in adults.
  • Lifespan of RBCs: about 120 ext{ days}; RBCs are cleared by macrophages in the spleen and liver through a process called hemolysis.
  • Erythropoiesis timeline: about 3 ext{–}5 ext{ days} to mature RBCs and load them with hemoglobin and lose organelles.
  • Daily production estimations mentioned: ~
  • About 4 imes 10^9 RBCs produced per day (per the lecture's figures).
  • Approximately 10^{10} RBCs present in circulation at any given time (as implied by the lecture's discussion of counts).
• Iron metabolism and hemoglobin synthesis
  • Iron is essential for hemoglobin function; without iron, hemoglobin cannot be formed correctly.
  • Iron dietary absorption occurs in the small intestine and can exist as Fe^{2+} or Fe^{3+} ions, depending on diet; the body converts dietary iron to usable forms for transport.
  • Iron distribution: once absorbed, iron goes to bone marrow for erythropoiesis; if iron stores are adequate, excess iron is stored in the liver.
  • Loss of iron occurs daily via sweat, urine, and feces; men typically lose about 0.9 ext{ mg/day}, women about 1.7 ext{ mg/day} due to menstruation.
• Vitamins and cofactors in hematopoiesis
  • Vitamin B12 and folic acid: essential for DNA replication during cell division; critical for cell proliferation in hematopoiesis.
  • Folic acid is particularly important during pregnancy due to rapid fetal DNA replication and cell division.
  • Copper and vitamin C: cofactors that assist in hemoglobin synthesis, though not part of the final Hb molecule.
• Blood typing and membrane components
  • Blood types are determined by a glycoprotein (a surface antigen) on RBCs that marks blood type (A, B, AB, O, etc.).
  • ABO blood group system discussed as a key topic later in the course.
  • RBC membrane proteins include spectrin and actin, which provide structural integrity and elasticity to the RBC membrane.
  • Hemoglobin structure involves four globin subunits and four heme groups; the heme iron is the binding site for oxygen.
• Red blood cell oxygen-binding capacity and saturation
  • Each RBC contains many hemoglobin molecules with iron-containing heme groups.
  • The percentage of binding sites occupied by oxygen reflects oxygen saturation levels; common exam-style interpretation includes the concept of saturation at 75%, 85%, etc. (as described in class examples).
  • Oxygen binding to hemoglobin enables transport; a lack of functional hemoglobin impairs oxygen delivery.

Important numerical references and typical ranges

• Hematocrit (RBC volume fraction)
  • Overall adult range: 42 ext{–}52 ext{ (men)}; 37 ext{–}48 ext{ (women)}
• RBC lifespan
  • Approximately 120 ext{ days}
• RBC production and population estimates (lecture figures)
  • Daily RBC production: approximately 4 imes 10^9 cells/day
  • Total circulating RBCs: on the order of 10^{10} cells
• Blood composition by volume (rough distribution mentioned)
  • RBCs (heaviest) settle at bottom; plasma on top; white cells + platelets occupy the middle (buff-ish region in centrifuge results not explicitly named in the transcript)
  • White blood cells plus platelets together constitute about 1 ext ext{%} of blood components beyond RBCs and plasma
• Iron loss comparisons
  • Men: about 0.9 ext{ mg/day}
  • Women (due to menstruation): about 1.7 ext{ mg/day}

Clinical and practical implications highlighted in the lecture

• Hypoxemia and clinical responses
  • Low blood oxygen triggers compensatory responses to increase oxygen transport capacity; in some chronic diseases (e.g., COPD), this can lead to persistent elevation of RBC counts.
• Hematopoietic tissue sources and lineage distinctions
  • Lymphoid lineage: T cells, B cells originate in lymphoid tissues; associated with lymphoid hematopoiesis.
  • Myeloid lineage: erythrocytes, monocytes, neutrophils, eosinophils, basophils originate from bone marrow; associated with myeloid hematopoiesis.
• Phlebotomy and lab workflows
  • Centrifuges are used to separate plasma, buffy coat (white cells/platelets), and erythrocytes.
  • In certain settings (e.g., jail labs), centrifuges and freezers are used to process and preserve samples when lab services are unavailable for long periods.
• Blood testing and clinical relevance
  • Plasma carries therapeutic and diagnostic substances; monitoring plasma components (e.g., albumin) is important for assessing viscosity and oncotic pressure.
  • RBC oxygen-carrying capacity is central to assessing anemia and related disorders; iron status critically affects hemoglobin synthesis.
• Practical exam and study tips mentioned
  • Study calendar will specify which chapters and labs are covered by each exam.
  • The instructor may explicitly call out exam-relevant points that appear verbatim on the test; students should note these items.
  • Handwritten notes are allowed for a limited time on tests to encourage active synthesis and retention of material.

Additional clarifications and terms introduced

• Key terms and their meanings
  • Hypoxemia: low oxygen content in the blood.
  • Hypoxia: insufficient oxygen delivery to tissues.
  • Hematopoiesis: the process of producing blood cells.
  • Erythropoiesis: the production of red blood cells.
  • Lymphoid: relating to lymphoid tissues and cells (e.g., T cells, B cells originating from lymphoid lineage).
  • Myeloid: relating to bone marrow-derived cells (e.g., most RBCs and myeloid leukocytes).
  • Heme: iron-containing component of hemoglobin that binds oxygen.
  • Bilirubin (note: transcription ends with “bilirubin” concept; bilirubin is a breakdown product of heme used in pigment formation and bile).
• Examples and memory aids mentioned in lecture
  • A mnemonic-like approach was used to remember that lymphoid cells are associated with lymphatic tissues and have letter-based naming (e.g., T cells, B cells).
  • The instructor uses direct references to upcoming exam questions to emphasize important topics and the expectation of word-for-word recall on certain items.

Study and course logistics recap

• First exam window
  • Week 5 focuses on heart and cardiovascular topics.
• Study materials and access
  • Course calendar lists exam coverage and lab coverage; students should review the calendar to know what content is on each exam.
  • A study guide or study pack may be provided; handwritten notes are permitted for a subset of time during tests.
• Instructor expectations and student support
  • Students are encouraged to ask questions during lectures if something is unclear.
  • The instructor aims to support student understanding and will offer help as needed, without judgment.
• Practical context reminders
  • Immunology, hematology, and cardiovascular topics connect to real-world settings, including clinical labs, patient care, and disease management.
• Miscellaneous notes
  • The instructor has health-related reasons for being “immobile” at present but expects to improve mobility.
  • The course includes a mix of lectures and labs that are integrated with the weekly modules; students should plan to attend both lectures and labs as required by their cohort.

Quick reference: key concepts to memorize for exams

• RBCs: structure, hemoglobin, iron dependence, oxygen transport, lack of nucleus/mitochondria in mature cells, lifespan ~120 ext{ days}
• Plasma proteins: albumin (viscosity, oncotic pressure), globulins (antibodies), fibrinogen (coagulation), liver as the production site
• Blood components distribution: RBCs ~hematocrit ranges; plasma; WBCs/platelets ~1%
• Iron metabolism: absorption in the gut, transport to bone marrow, daily loss rates (men vs. women), role of B12 and folic acid in cell division, copper and vitamin C as cofactors
• Hematopoiesis pathways: erythropoiesis; lymphoid vs myeloid origins; bone marrow vs spleen roles
• Oxygen transport mechanics: hemoglobin iron, heme group, O₂ binding and release dynamics
• Hemolysis and bilirubin pathway (conceptual end of lecture): RBC destruction, iron recycling, bilirubin formation
• Blood viscosity and osmolarity regulation; kidney roles in maintaining osmolarity and fluid balance
• Blood typing basics: surface glycoprotein antigens on RBCs; ABO system introduction

Note: If you’d like, I can tailor these notes to a specific chapter or add more diagrams and example problems to match your course syllabus.