Chapter 11 Blood Functions transports vital substances distributes heat Blood Cells form mostly in red bone marrow red blood cells white blood cells platelets.

Chapter 11Blood

Functions• transports vital substances• distributes heat

Blood Cells• form mostly in red bone marrow• red blood cells• white blood cells• platelets (cell fragments)

11-1

Blood Volume

• varies with• body size• changes in fluid concentration• changes in electrolyte concentration• amount of adipose tissue

• about 8% of body weight• about 5 liters

11-2

Blood Composition

11-3

Red Blood Cells

• erythrocytes• biconcave• one-third hemoglobin• oxyhemoglobin• deoxyhemoglobin

• can readily squeeze through capillaries• lack nuclei and mitochondria

11-4

Red Blood Cell Count

• number of RBCs in a cubic millimeter of blood

• 4,600,000 – 6,200,000 in males

• 4,200,000 – 5,400,000 in adult females

• 4,500,000 – 5,100,000 in children

• reflects blood’s oxygen carrying capacity

11-5

Red Blood Cell Production

• low blood oxygen causes kidneys and liver to release erythropoietin which stimulates RBC production

• vitamin B12, folic acid and iron necessary

11-6

Types of Anemia

• iron deficiency anemia• hemoglobin deficient• lack of iron

• pernicious anemia• excess of immature RBCs• inability to absorb B12

• sickle cell anemia• abnormal shape of RBCs• defective gene

11-7

Polycythemia- excess number of rbcs

White Blood Cells

• leukocytes• protect against disease• interleukins and colony-stimulating factors stimulate development

• granulocytes• neutrophils• eosinophils• basophils

• agranulocytes• lymphocytes• monocytes

11-8

Lymphocytes

• T cells• B cells• important in immunity• produce antibodies• 25% - 33% of leukocytes• decreased T Cells in AIDS

11-9

White Blood Cell Counts

• number of WBCs per cubic millimeter of blood• 5,000 – 10,000 per cubic millimeter of blood• leukopenia • low WBC count; below 5,000 per cubic mm• AIDS

• leukocytosis • high WBC count; more than 10,000 per cubic mm• acute infections, leukemia

• differential WBC count• lists percentages of types of leukocytes• may change in particular diseases 11-10

Blood Platelets

• thrombocytes• cell fragments of megakaryocytes• 130,000 – 360,000 per cubic millimeter of blood• helps control blood loss from broken vessels

11-11

Hemostasis and Blood Clots

• stoppage of bleeding

11-12

• thrombus – abnormal blood clot• embolus – blood clot moving through blood

Blood Plasma

• straw colored• liquid portion of blood• 55% of blood

11-13

Plasma ProteinsAlbumins• most numerous plasma proteins• originate in liver• help maintain osmotic pressure of blood

Gamma Globulins• originate in lymphatic tissues• constitute the antibodies of immunity

11-14

Gases and Nutrients

Gases• oxygen• carbon dioxide• nitrogen

Nutrients • amino acids• simple sugars• nucleotides• lipids

11-15

Plasma Electrolytes

• sodium• potassium• calcium• chloride• bicarbonate• phosphate• sodium and potassium most abundant

11-16

ABO Blood Group

11-17

Agglutination

11-18

Preferred and Permissible Blood

Types for Transfusion

11-19

O universal donorAB universal recipient

Rh

• Rh factor is another antigen found on about 85% of the population

• Erythroblastosis fetalis

• RhoGAM

11-20