Transport Blood

Blood and Blood Cells Whole blood is slightly heavier and three to four times more viscous than water. A blood sample is usually about 45% cells by volume. Hematocrit - % of cells contained in a blood sample.

Blood Cells Most blood cells are red cells The remaining 55% of a blood sample is clear, straw-colored liquid called plasma. Plasma is a complex mixture of water, amino acids, proteins, carbohydrates, lipids, vitamins, hormones, electrolytes, and cellular wastes.

Red Blood Cells Also called erythrocytes. Bioconcave discs in order to transport gases. Each red blood cell is about 1/3 hemoglobin by volume. Hemoglobin carries oxygen.

Hemoglobin When it combines with oxygen = oxyhemoglobin(bright red) When oxygen is released = deoxyhemoglobin (darker)

White Blood Cells Also called leukocytes. Function to protect against diseases. Develop from hemocytoblasts in response to hormones. Hormones fall into two groups: Interleukins Colony-stimulating factors (CSFs)

Function of White Blood Cells Protect against infection in various ways Some phagocytize(eat) bacterial cells in the body Others produce proteins(antibodies) that destroy or disable foreign particles

Neutrophils and Monocytes Most mobile and active phagocytic leukocytes. Monocytes can engulf large objects Neutrophils engulf same-sized or smaller objects. Both contain many lysosomes

Lymphocytes Are important in immunity. Produce antibodies that attack specific foreign substances that enter the body.

White Blood Cell Counts A total number of white blood cells exceeding 10, 000 per cubic mm of blood is called leukocytosis = an acute infection somewhere in the body. Example: appendicitis.

Leukopenia A total white blood cell count of 5000 per cubic mm of blood. Indicates typhoid fever, influenza, measles, mumps, chicken pox, AIDS, or poliomyelitis.

DIFF Differential White Blood Cell Count Lists percentages of the types of leukocytes in a blood sample. Useful because the relative proportions of white blood cells may change in a particular disease. For example, the number of neutrophils usually increases during bacterial infections. The number of eosinophils increases during parasitic infections and allergic reactions. In AIDS, the number of a certain type of lymphocyte drops sharply.

Blood Platelets Also called thrombocytes. Are not complete cells. Arise from very large cells in red bone marrow called megakaryocytes. Platelets help close breaks in damaged blood vessels and initiate formation of blood clots.

Blood Plasma Assignment: Pg. 325, 1-3, 8, 9, 10, 11, 12, We will go through this on Friday. Assignment: Pg. 325, 1-3, 8, 9, 10, 11, 12, Critical thinking #1

5 Types of White Blood Cells Differ in size, nature of their cytoplasm, shape of their nucleus, and staining characteristics. Neutrophil-lobed nucleus Eosinophil-stains red Basophil- stains deep blue Monocyte- largest blood cells Lymphocyte- large, round nucleus