Page 125 - 84 human physiolofy part-1

Blood Physiology

then water). A drop in pH is called Acidic. This condition is also called Acidosis. A jump in pH higher
then 7.45 is called "Alkalis". To maintain the homeostasis (or balance,) the blood has tiny molecules
within the RBC that help prevent drops or increases from happening.

Destruction

Red blood cells are broken down and hemoglobin is released. The globin part of the hemoglobin is
broken down into amino acid componants, which in turn is recycled by the body. The iron is recovered
and returned to the bone marrow to be reused. The heme portion of the molecule experiences a
chemical change and then gets excreted as bile pigment (bilirubin) by the liver. Heme portion after
being broken down contributes to the color of feces and your skin color changing after being bruised.

White Blood Cells

Shape

White blood cells are different from red cells
in the fact that they are usually larger in size 10-
14 micrometers in diameter. White blood cells do
not contain hemoglobin which in turn makes them
translucent. Many times in diagrams or pictures
white blood cells are represented in a blue color,
mainly because blue is the color of the stain used From left to right diagram of Erythrocyte, Thrombocyte, and
to see the cells. White blood cells also have Leukocyte
nucleii, that are some what segmented and are
surrounded by electrons inside the membrane.

Functions

White blood cells (leukocytes) are also known as "WBC's". White blood cells are made in the
bone marrow but they also divide in the blood and lymphatic systems. They are commonly amoeboid
(cells that move or feed by means of temporary projections, called pseudopods (false feet), and escape
the circulatory system through the capillary beds. The different types of WBC's are Basophils,
Eosinophils, Eeutrophils, Monocytes, B- and T-cell lymphocytes. Neutrophils, Eosinophils, and
Basophils are all granular leukocytes. Lymphocytes and Monocytes are agranular leukocytes.
Basophils store and synthesize histamine which is important in allergic reactions. They enter the tissues
and become "mass cells" which help blood flow to injured tissues by the release of histamine.
Eosinophils are chemotaxic and kill parasites. Neutrophils are the first to act when there is an infection
and are also the most abundant white blood cells. Neutrophils fight bacteria and viruses by
phagocytosis which mean they engulf pathogens that may cause infection. The life span of a of
Neutrophil is only about 12-48 hours. Monocytes are the biggest of the white blood cells and are
responsible for rallying the cells to defend the body. Monocytes carry out phagocytosis and are also
called macrophages. Lymphocytes help with our immune response. There are two Lymphocytes: the B-
and T- cell. B-Lymphocytes produce antibodies that find and mark pathogens for destruction. T-
Lymphocytes kill anything that they deem abnormal to the body.

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