Lecture_Two - Class notes-Lecture Two Whole blood Whole...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Class notes-Lecture Two Whole blood Whole blood consists of solids and liquids. The solids of the blood include red blood cells, white blood cells, and platelet. The liquid portion of the blood (plasma) is composed of water, amino acids, proteins, carbohydrates, lipids, vitamins, hormones, electrolytes and cellular wastes. If an anticoagulated blood sample is allowed to stand in a tube the solids will settle to the bottom and become separated from the liquid portion of the blood. When the amount of solids is measured and compared to the amount of liquid the percentage each portion represents can be calculated. As a rule, for every 100 ml of blood there are about 45% solids (males, 40-54%, females 38-47%). This percentage is called the hematocrit (hct) . In other words the hematocrit tells you the percent of solids in a sample of blood as compared to the liquid (plasma). Normally the Hct parallels the red blood cell count. Because the majority of the solids are red blood cells, and a large portion of the red blood cell is hemoglobin, a ratio typically exists between the Hct and Hb in that the Hb value is roughly one third of the Hct value. Knowing this if only the Hct is reported you can divide the value by 3 to estimate Hb. If the Hb is know you can multiply it by 3 to estimate the Hct. How might the Hct level be affected by the persons state of hydration? Red blood cells Red blood cells ( erythrocytes ) are mainly hemoglobin . Each red blood cell is about 1/3 hemoglobin by volume. Red blood cells (RBC s) are produced in the red bone marrow. If released when they are mature, RBC s have no nucleus. However, if conditions like loss of blood and low oxygen levels in the blood stimulate extra release of cells, some nucleated cells may be allowed into circulation. The presence of nucleated RBC s indicates intense erythropoietic activity. Red blood cell production is controlled by the hormone erythropoietin, which is released from the
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 3

Lecture_Two - Class notes-Lecture Two Whole blood Whole...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online