Blood Recording (W2025)

Course Calendar Update

• New Schedule: A rearranged calendar has been shared and is accessible in the course content section.

• First Class Review: The initial class titled "Course Introduction" includes student conduct policies, medical terminology, and study tips.

Exam Adjustments

• Regular Class Review: Discussed the rearrangement of topics due to a recent snow day.

• Current Topic: Blood studies being conducted today, which is prerequisite for upcoming lymphatic system discussions.

• Reading Break: Follows next week (students have time for self-study).

• Endocrine System Exam Date: Moved exam to March 11 to provide more study time. Initially planned for March 4.

• Next Session: Respiratory system discussion on March 6, which will not be included in upcoming exam.

Examination Progress Discussion

• Previous Exam Results:

  • Average score: Approximately 70.6%, higher than the usual 68% average.

  • Some scores below 50% were noted, but a significant number scored in the 90s.

  • Emphasis on not panicking over initial low scores as there are more exams ahead.

Course Challenges and Strategies

• Material Volume: Acknowledgment of the course's extensive material, significantly more challenging than typical high school coursework.

• Study Strategies: Encourage students to find study methods that work for them. Suggested techniques include:

  • Repeated reading

  • Flashcards

  • Oral recitation

• Understanding Pace: Students should balance studying with personal life and work commitments.

Exam Policy and Support

• Individual Review: Offered individual Zoom sessions for exam review upon request.

• Upcoming Coverage for Second Exam: Will cover sensory systems to endocrine.

Blood as a Connective Tissue

• Characteristics of Blood:

  • Connective tissue with specialized cells (red blood cells, white blood cells, platelets).

  • Blood matrix: Plasma constitutes majority (fluid portion).

  • Oxygen-rich blood appears bright red due to oxygen binding with hemoglobin, whereas oxygen-poor blood appears darker.

• Blood Composition:

  • Approximately 5 liters in the body.

  • Common donation amount is about 450 mL.

  • Fun Fact: Blood historically associated with essence of life; terms like "blue blood" refer to nobility.

Functions of Blood

• Transportation: Carries gases (O2, CO2), nutrients, hormones, and wastes.

• Regulation: Maintains pH, water content, and body temperature.

• Protection: Eliminates pathogens and prevents excessive blood loss via clotting.

Overview of Blood Cells

• Red Blood Cells (Erythrocytes):

  • Lifespan: 80-120 days, filled with hemoglobin for oxygen transport.

  • No organelles, thus do not undergo division and are destroyed in the liver and spleen.

• White Blood Cells (Leukocytes):

  • Larger than red blood cells, involved in immune responses.

  • Types include neutrophils (phagocytosis of pathogens), basophils (inflammatory response), and eosinophils (allergic reactions).

• Platelets (Thrombocytes):

  • Involved in clotting, derived from megakaryocytes.

  • Form a temporary plug and contribute to coagulation.

Blood Clotting Process

• Hemostasis: Sequence of events to stop bleeding after an injury.

  • Vasoconstriction occurs immediately, followed by platelet plug formation.

  • Clotting cascade activates fibrinogen to fibrin, which stabilizes the clot.

Blood Type System

• ABO Blood Groups: Four main types A, B, AB, and O based on antigens present on red blood cells.

  • Type O: Universal donor, lacks antigens.

  • Type AB: Universal recipient, contains no antibodies to attack incoming blood antigens.

• Rh Factor:

  • Presence of Rh antigen determines positive or negative blood type; a negative mother may require RhoGAM after delivering a positive baby to prevent immunization against Rh factor in future pregnancies.

Conclusion and Questions

• Encouraged to study the new material and review the blood study group. Addressed the need for understanding blood types and their significance in transfusions.