Blood and Hematopoiesis

Functions of Blood

Hematopoiesis Higher Vertebrates Bone marrow, spleen lymph nodes, thymus Bone marrow, spleen lymph nodes, thymus Lower Vertebrates Liver, kidney capsule, cranial capsule, genital organs Liver, kidney capsule, cranial capsule, genital organs Embryonic and Fetal Yolk sac, liver, spleen, and bone marrow Yolk sac, liver, spleen, and bone marrow

Blood Plasma Homogeneous, alkaline fluid Contains albumin, globulins, water, inorganic ions, nutrients, and hormones Percent of plasma in whole blood is about 55%

Red Blood Cells

Erythrocyte A: Erythrocyte: B: Platelets

Reticulocyte A: Reticulocyte B: Erythrocyte

Clinical Connections

Sickle Cell Anemia Source: en.wikipedia.org/wiki/Sickle-cell disease Anemia is the failure to maintain adequate hemoglobin concentration RBCs assume an abnormal, sickle shape which decreases flexibility Occurs because of a mutation in the hemoglobin gene

Polycythemia Vera Source:

Granulocytes

Neutrophil A: Neutrophil B: Erythrocyte

A B

A B

Eosinophil A: Eosinophil: B: Erythrocyte.

A

Basophil A: Basophil B: Erythrocyte. C: Thrombocyte

A

Agranulocytes

Monocyte A: Monocyte B: Erythrocyte

Lymphocyte A: Lymphocyte B: Erythrocyte

Clinical Connections

Leukemia Broad term covering a wide spectrum of diseases - acute and chronic Lymphocytic or myelogenous Characterized by an abnormal increase in immature WBCs Diagnosed via blood smear or bone marrow biopsy Source:

Megakaryocyte & Platelets A: Megakaryocytes B: Platelets or thrombocytes

Review Name the cell types, percentage, lifespan and function

Review WBC% of WBCLifespanFunction NeverNeutrophil40-75%Circulation: 1 week Tissue: 1-4 days Phagocyte LetLymphocyte20-50%Circulation: months to yearsGeneral immunity Inflammatory Response MonkeysMonocyte2-10%Circulation: 2-5 days Tissue: 1-3 months Phagocyte EatEosinophil1-6%Circulation: 2 weeksParasitic invasion BananasBasophil < 1% Circulation: 1-2 yearsAllergic response Secretes histamine and heparin RBCLifespan Erythrocytes120 days

Lymphatic System

Lymphocyte Role in Immunity B Lymphocytes Originate from myeloid tissue and mature within bone marrow Originate from myeloid tissue and mature within bone marrow Activated by antigens and eventually differentiate into plasma cells that secrete antibodies Activated by antigens and eventually differentiate into plasma cells that secrete antibodies T Lymphocytes Originate from myeloid tissue and complete maturation in the thymus Originate from myeloid tissue and complete maturation in the thymus Role in the destruction of foreign macromolecules, viruses and antigens without producing antibodies Role in the destruction of foreign macromolecules, viruses and antigens without producing antibodies

Lymph and Lymphatics Lymph Contains water, electrolytes, and variable amounts of protein Returned to the circulatory system via thoracic duct and main lymphatic duct Lymphatic Vascular System Principle function is to return fluid, plasma proteins, lymphocytes, and immunoglobins back to circulation Picks up extracellular fluid from tissues and returns it to the circulatory system

Lymph Node Lymph Nodes Consists of a cortex and medulla Endothelial lined channels with phagocytic cells that clear foreign matter and bacteriaCortex The cortex appears darker and contains follicles The inner portion of the follicle is the germinal center Germinal center contains lymphoblasts, monoblasts, and plasma cells

Lymphoid Organs Spleen Largest lymphoid organ Consists of red and white pulp Also a “storage” area for bloodThymus First lymphoid organ to form First lymphoid organ to form Center for T cell development Center for T cell development Lymphatic Aggregations Peyer’s patches in the ileum Peyer’s patches in the ileum Appendix Appendix Tonsil Tonsil

Lymph Node A: Medulla B: Cortex C: Lymph nodules D: Germinal center D A B C

A B

A B C D

Germinal Center A B A: Cortex of lymph nodule B: Germinal center

A

Peyer’s Patch A B C D A: Mucosa of the ileum. B: Submucosa C: Peyer’s Patches D: Germinal center.

Practice

Appendix A B C C D D A: Invagination of the mucosa. B: Simple columnar epithelium. C: Lymphatic Nodule D: Germinal Center

Spleen A D B A A C A: White pulp B: Red pulp C: Trabecula D: Germinal Center.

A C B C Practice A: DCCTRA with elastic fibers B: Red pulp C: White pulp

Thymus A B C D E A: Cortex B: Medulla. C: Lobules of the thymus. D: Interlobular septa E: Hassall’s corpuscle.

A B B C

A B C

Tonsil A B C A: Lymph Nodule B: Germinal center C: Stratified squamous epithelium

A B

Lymphatic Vessel AB A: Lymphatic vessels are lined with endothelium which is simple squamous epithelium. B: Lymphatic valve