Circulatory System: Blood And Vessels Flashcards
What Are The Components of Blood?
Platelets (55%)
Erythrocytes (45%)
Leukocytes
Plasma
What Is Plasma?
A Transport Medium For Inorganic/Organic Substances
Consists Of:
- 90% Water
- Na+ and Cl–
- Plasma proteins (Organic)
- (Other Organic): Waste Products, Dissolved
Gases + Hormones
What Are The Key Plasma Proteins?
- Albumins
- Globulins (Alpha, Beta, Gamma)
- Fibrinogen
Describe Erythrocytes.
Red Blood Cells, Transport Oxygen in Blood Structure Contains Globin (Protein) and Haem (Non-Protein)
Lack Nucleus and Organelles
Mature Erythrocytes only contain few key non-renewable enzymes
Describe Haemoglobin.
A Tetramer Containing x2 Alpha and x2 Beta Subunits with Haem Groups
List Erythrocyte Development Stages.
- Pluripotent Stem Cell → Myeloid Stem Cell
- Myeloid Stem Cell → Erythroblast
- Erythroblast → Reticulocyte
- Reticulocyte → Erythrocyte
Describe:
Pluripotent Stem Cell → Myeloid Stem Cell
- Pluripotent Stem Cells Commit to Myeloid
Lineage - Commitment Regulated By Transcription
Factors (PU.1 + GATA-2) - Commitment Driven By Interleukin-3 and
Stem Cell Factor (SCF)
Describe:
Myeloid Stem Cell → Erythroblast
Erythroid Lineage Commitment Established using:
GATA-1: Activates Erythroid-Specific Genes
KLF1: Drives Haemoglobin Synthesis + RBC Maturation
Erythropoietin:
Hormone binds → Erythroid Precursor Receptors
Survival, Proliferation + Differentiation into Proerythroblasts Promoted
Describe:
Erythroblast → Reticulocyte
Erythroblasts Maturation Through Various Stages
Key Stages:
- Hemoglobin synthesis: Iron (Delivered by
Transferrin) Incorporated into Haem Groups - Nuclear Condensation: Nucleus Shrinks and
Is Enucleated In Bone Marrow with
Macrophages - Reticulocyte Formed
Describe:
Reticulocyte → Erythrocyte
- Reticulocytes enter Bloodstream, Mature
Into Erythrocytes - Residual organelles lost, Cell Membrane
Remodeled into Biconcave Shape - Haemoglobin packing Complete, Cell
Becomes Fully Functional
What is The Role of The Bone marrow In Relation To Erythrocytes?
To Continuously replace Erythrocytes using Erythropoiesis, as they have a short life span
How Is Erythropoiesis Controlled?
Controlled By Kidneys
Mechanism:
- Kidneys Detect Low O2 Carrying Capacity of
Blood - Kidneys Secrete Erythropoietin Into Blood
- Erythropoietin Stimulates Erythropoiesis by
Red Bone Marrow - Additional Circulating Erythrocytes Increase
O2 Carrying Capacity - Increased O2 Carrying Capacity Relieves
Initial Stimulus That Triggered Erythropoietin
Secretion
What Are Reticulocytes?
Immature Erythrocytes
What Is Synthetic Erythropoietin Used For?
To Boost RBC Production In Individuals With Suppressed Erythropoietic Activity
What Is Polycythemia?
Excess Erythrocytes Circulating In Blood, Causes Elevated Hematocrit
Consists Of 2 Types:
- Primary
- Secondary
What Are The Different Blood Types?
- Type A
- Type B
- Type AB
- Type O
What is Different Between The Blood Groups?
The Antigens Each Blood Type Contains
Type A: A Antigens
Type B: B Antigens
Type AB: A and B Antigens
Type O: (Doesn’t Have A or B)
What Blood Groups Are Compatible?
Type O
Can Donate To: All Blood Types
Can Receive: Only Type O Blood
Type A
Can Donate To: A and AB
Can Receive: A and O
Type B
Can Donate To: B and AB
Can Receive: B and O
Type AB
Can Donate To: AB
Can Receive: All Blood Types
How is Blood Rh Positive/Negative Established?
By Identifying Rh Factor
Rh Factor Present: Rh Positive
Rh Factor Absent: Rh Negative
Which Antibodies Does Each Blood Group Contain:
Type A: Anti-B
Type B: Anti-B
Type AB: None
Type O: Anti A & B
What Would Happen If Incompatible Blood is Transfused?
Donor RBCs Have Antigens that react with recipient’s plasma antibodies (anti-X antibodies)
Antibodies in Recipient’s Plasma Bind To Donor RBC antigens, forming Antigen-Antibody Complexes
- Complement Activation
Immune System Activates Complement proteins, which punch holes in Donor RBC membranes.
This triggers haemolysis, releasing hemoglobin into bloodstream.
- Hemoglobin Release & Kidney Damage
Free hemoglobin clogs kidney tubules, causes:
Acute Kidney Injury (Dark Urine Due To Hemoglobinuria)
Severe Pain In Lower Back/Loins
- Clotting Cascade Activation
Damaged RBCs Release Pro-Clotting Factors, Leads to:
Disseminated Intravascular Coagulation (DIC)**: Widespread clotting → depletion of clotting factors → uncontrolled bleeding.
- Systemic Effect
Massive Immune Response Causes: Fever, Chills, Nausea, Vomiting, Rapid Heart Rate, Hypotension (low blood pressure).
What Are Leukocytes?
Mobile Units Of The Body’s Immune Defense System
What Are The 5 Types Of Leukocytes?
- Neutrophils
- Eosinophils
- Basophils
- Monocytes
- Lymphocytes
Describe The Function Of Each Leukocyte?
Neutrophils: Engulf + Destroy Bacteria Intracellularly
Eosinophils: Associated With Allergic Conditions + Parasite infestations
Basophils: Synthesize + Store Histamine and Heparin
Monocytes: Perform Phagocytosis
Lymphocytes: Provide Specific Immune Defense
