Human blood – Structure and Function Biochemical and cellular aspects of blood.

Blood StructureStructure Water with chemicals with cells suspended in it.Water with chemicals with cells suspended in it. FunctionsFunctions Transport gases (O 2, CO 2 ), nutrients, hormones, wasteTransport gases (O 2, CO 2 ), nutrients, hormones, waste Distributes heatDistributes heat Maintains homeostasisMaintains homeostasis

Blood – Connective Tissue Connective tissue = cells + fluid matrixConnective tissue = cells + fluid matrix Blood = fluid matrix for movementBlood = fluid matrix for movement

Blood Composition  Plasma = H2O + chemicals = 55%  Formed Elements = cells and platelets = 45%

Blood Components- Formed Elements  Red blood cells = erythrocytes = cells, no nucleus when mature  White blood cells = leukocytes = cells, with nucleus  Platelets = thrombocytes = not cells, small chunks of cell  ALL formed in bone marrow. Production stimulated by hormones RBC, platelet, WBC

Red Blood Cells Formed in bone marrowFormed in bone marrow No nucleus when matureNo nucleus when mature Limited life spanLimited life span Transport O 2 and CO 2Transport O 2 and CO 2 Hemoglobin = red colored protein that O 2 binds toHemoglobin = red colored protein that O 2 binds to Also called ErythrocytesAlso called Erythrocytes Red Blood Cell White Blood Cell

platelets Not cells, cytoplasmic fragments of a large cellNot cells, cytoplasmic fragments of a large cell Produce protein (fibrin) when activated with clotting factorsProduce protein (fibrin) when activated with clotting factors Fibrin traps RBC’s to produce a blood clotFibrin traps RBC’s to produce a blood clot

Blood and the immune response  The immune response is carried out by white blood cells (leukocytes) that leave the blood stream  When leukocytes leave the blood stream they are ‘fighting’ as part of an active immune response

Types of leukocytes

Granulocytes Neutrophil video Eosinophil video Basophil What functions do these perform in the immune response?

Types of leukocytes Agranulocytes Lymphocyte video Monocyte What functions do these perform in the immune response? video

Types of leukocytes

Differential WBC Count Detection of changes in numbers of circulating WBCs Indicates infection, poisoning, leukemia, chemotherapy, parasites or allergy reaction Normal WBC counts neutrophils 60-70% (up if bacterial infection) lymphocyte 20-25% (up if viral infection) monocytes % (up if fungal/viral infection) eosinophil % (up if parasite or allergy reaction) basophil <1% (up if allergy reaction or hypothyroid)

Pathological conditions: RBC’s Sickle Cell Anemia

Pathological conditions: RBC’s Anemia

Pathological conditions: WBC’s

Infectious Mononucleosis

Pathological conditions: WBC’s Eosinophilia

Complete Blood Cell Counts Using a hematocytometer

The grid has specified dimensions so that the area covered by the lines is known, which makes it possible to count the number of cells in a specific volume of solution.

Complete Blood Cell Counts Using a hematocytometer