White Blood Cells - COHS Anatomy & Physiology

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Chapter 11
The Cardiovascular System: Blood
Anatomy & Physiology
• “The living body is in constant communication
with it’s external environment. Nutrients are
absorbed through the lining of the digestive tract,
gases move across the epithelium of the lungs,
and wastes are excreted in the feces and urine.
Even though these chemical exchanges occur at
specialized sties, they affect every cell, tissue, and
organ in a matter of moments because all parts of
the body are linked by the cardiovascular system,
an internal transport network.” (p. 365)
Chapter 11
The Cardiovascular System: Blood
Objective 6
6. Categorize the various white blood cells on the
basis of their structures and functions.
White Blood Cells
• WBC’s are also
known as leukocytes
• Recognized and
distinguished from
RBC’s by
• Larger size
• Presence of a nucleus
• Presence of other
organelles
• Lack hemoglobin
• Help defend the body
by
• Removing pathogens,
toxins, and waste
• Removing abnormal or
damaged cells
• Capable of amoeboid
movement (crawl)
• Migrate out of
bloodstream
• Called diapedesis
Categories of WBC’s
• Granulocytes
• Contain abundant number of stained granules
• neutrophils, eosinophils, & basophils
• Agranulocytes
• Have very few, if any, stained granules
• monocytes & lymphocytes
White Blood Cells
Granulocyte: Neutrophil
• Nucleus
is contorted
After
eating
1-2
into bacteria,
2-5 lobes they
dozen
• Phagocytic
dies
and burst open.
• First“insides”
to arrive at
Their
attract
injury
more neutrophils to
• Specialize
in eating
the
site. Dead
bacteria
neutrophils and cell
• 50-70% of WBC’s
debris form pus.
Granulocyte: Eosinophil
• 2-lobed nucleus
• Attack object coated
with antibodies
• They like parasites
and responding to
allergic reactions
• 2-4% of WBC’s
Granulocyte: Basophil
• Filled with numerous
granules
• Rare – less than 1%
of WBC’s
• Attracted to tissue
damage where they:
• Release heparin
• Prevents blood clotting
• Release histamine
• Enhances inflammation
started by mast cells
Agranulocyte: Monocyte
• Very large oval or
kidney bean shaped
nucleus
• Migrate through
tissues
• Called macrophages
• phagocytic
• Very large, 2x bigger
than RBC’s
• 2-8% of WBC’s
Agranulocyte: Lymphocyte
• Almost completely
filled by large round
nucleus
• Migrate between
blood and tissues
• Attack foreign cells
• Secrete antibodies
• 20-30% of WBC’s
Changes in WBC Abundance
• Leukopenia – indicates reduced numbers of
WBC’s
• Leukocytosis – refers to excessive numbers of
WBC’s
• May indicate leukemia, a cancer of bloodforming tissue
• Sometimes indicated by abnormal or immature
WBC’s
• Can make skin look white and blood gray-ish in
appearance
• from SO MANY white blood cells….
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