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Blood Physiology

royal family. Alexandra, granddaughter to Queen Victoria, married Nicholas (Tsar of Russia in the
1900s). Alexandra was a carrier of the disease and passed the disease to their first son, Tsarevich Alexi,
who was heir to the throne of Russia. The family tried to keep their son's secret from the people, but
Alexi suffered with serious bruises and extreme pain. The family found help from a monk named
Rasputin. He kept their secret and gained a great deal of power over the family, making them think he
was their only hope. During this time of great turmoil in Russia, Nicholas and Alexandra spent most of
their attentions on their son, and not on the people. It wasn't long before the Bolshevik Revolution of
1917 began.

Factor V Leiden

The opposite of Hemophilia, Factor V Leiden is the name given to a variant of human factor V that
causes a hypercoagulability disorder. In this disorder the Leiden variant of factor V, cannot be
inactivated by activated protein C. Factor V Leiden is the most common hereditary hypercoagulability
disorder amongst Eurasians. It is named after the city Leiden (The Netherlands), where it was first
identified in 1994 by Prof R. Bertina et al. Those that have it are at a slightly higher risk of developing
blood clotts than those without. Those that test positive for factor V should avoid (oral contreseptives,
obesity, smoking, and high blood pressure.)

Anemia

Anemia (AmE) or anaemia (BrE), from the Greek ( ναιμία) meaning "without blood", refers to aἈ
deficiency of red blood cells (RBCs) and/or hemoglobin. This results in a reduced ability of blood to
transfer oxygen to the tissues, causing hypoxia. Snce all human cells depend on oxygen for survival,
varying degrees of anemia can have a wide range of clinical consequences. Hemoglobin (the oxygen-
carrying protein in the red blood cells) has to be present to ensure adequate oxygenation of all body
tissues and organs.

The three main classes of anemia include excessive blood loss (acutely such as a hemorrhage or
chronically through low-volume loss), excessive blood cell destruction (hemolysis) or deficient red
blood cell production (ineffective hematopoiesis). In menstruating women, dietary iron deficiency is a
common cause of deficient red blood cell production.

Sickle cell

Sickle-cell disease is a general term for a group of genetic disorders caused
by sickle hemoglobin (Hgb S or Hb S). In many forms of the disease, the red
blood cells change shape upon deoxygenation because of polymerization of the
abnormal sickle hemoglobin. This process damages the red blood cell
membrane, and can cause the cells to become stuck in blood vessels. This
deprives the downstream tissues of oxygen and causes ischemia and infarction.
The disease is chronic and lifelong. Individuals are most often well, but their Image of RBC's with
lives are punctuated by periodic painful attacks. In addition to periodic pain, Sickle Cell mutations.
there may be damage of internal organs, and/or stroke. Lifespan is often
shortened with sufferers living to an average of 40 years. It is common in people from parts of the
world where malaria is or was common, especially in sub-Saharan Africa or in descendants of those

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