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Chapter 11: Blood

BIO 105

Spring 2016

Functions of the Blood

1. Transportation

2. Regulation

3. Protection

Composition of blood

Connective Tissue

55% plasma

45% formed elements

Plasma

• Made up of 92% water and 7-8% dissolved substances

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19_01bFormed Elements

Formed Elements

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Red blood cell lifespan

• Lifespan of 120 days

• “Old” RBCs eventually end up in the spleen or

liver

• Cell breakdown causes the release of

hemoglobin and the production of bilirubin

RBC productionAnemia

Anemia – condition in which the blood’s

ability to carry oxygen is reduced

Iron-deficient anemia

Aplastic anemia

Sickle cell anemia

Pernicious anemia

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White blood cells

• Make up less than 1% of whole blood

• Help defend the body against disease

• Remove wastes, toxins, and damaged or

abnormal cells

• Not confined to the bloodstream

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Leukemia

Leukemia is a cancer of the blood or bone marrow

• There is a proliferation of immature WBCs

• Remain relatively unspecialized, so individuals prone to infections

• Bone marrow gets “crowded,” and has a reduced ability to produce other cells, like RBCs and platelets

Platelets

• Platelets (thrombocytes)—cell fragments

that are necessary for clotting of the blood

Clotting cascade (abbreviated) Bleeding disorders

• Hemophilia

• Thrombosis

• Embolism

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Blood Typing

• Human blood is classified into different blood types

(ABO) depending on the presence of proteins on the

surface of the RBCs

– Type A blood—type A antigen on the surface of

the RBC.

– Type B blood—type B antigen on the surface of

the RBC.

– Type AB blood—type A and B antigens on the

surface of the RBC.

– Type O blood—has no antigens on the surface of

the RBC.

Blood Types

Blood Typing

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Rh factor