Blood

1
Blood

• Marie Cerná

2
Blood

• The blood consists of
• a suspension of special cells - formed elements
  
• in a liquid called plasma
• In an adult man
• the blood is about 1/12th of the body weight
• and this corresponds to 5-6 liters

3
Hematocrit relation (volume ) of plasma (55
) to cells (45 )
4
Blood functions

• maintenance of homeostasis
• osmotic pressure stability (0.15 mM NaCl)
• pH 7.4 (buffer system - HCO3-)
• carries respiratory gases
• oxygen O2 to tissues (by the hemoglobin in red
  cell)
• carbon dioxide CO2 from tissues (by the plasma
• in the form of soluble carbonates HCO3-)
• conveys nutrients (amino acids, sugars, fatty
  acids)
• gathers waste products of metabolism which will
  be excreted through the renal filter
• carries hormones, enzymes, vitamins, mineral
  salts
• performs the defense of the organism
• performs thermoregulation of the organism

5
Plasma

• is a slightly alkaline fluid, with a typical
  yellowish color
• can be obtained by centrifugation
• cells free serum - clotted
• plasma - unclotted due to adding
  anticoagulants
• It consists of 90 water and 10 dry matter
• 9/10 is made up by organic substances
• 1/10 is made up by minerals
• These organic substances are composed of
• glucides (glucose)
• lipids (cholesterol, triglycerides,
  phospholipids, lecithin, fats)
• proteins (globulins, albumins, fibrinogen)
• glycoproteins, amino acids
• hormones, vitamins, minerals
• The mineral substances are dissolved in ionic
  form
• that is dissociated into positive and negative
  ions

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Plasma / Serum
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Hematic cells

• Special cells
• erythrocytes
• leukocytes
• thrombocytes
• are not considered real cells

8
Erythrocytes (red cells) providing oxygen in
hemoglobin to tissues

• 4.5 .106 / mm3 4.5 .1012 / l in female
• 5 . 106 / mm3 5 .1012 / l in male
• 7 . 106 / mm3 7 .1012 / l in newborn
• 8 . 106 / mm3 8 .1012 / l in sportsmen
• size 7,2 µm in diameter

• In man and in all mammals
• they are devoid of a nucleus
• In the other vertebrates
• they have a nucleus
• the lack of nucleus allows more room for
  hemoglobin gt
• the shape of a biconcave lens raises the surface
  and cytoplasm volume ratio.
• gt more efficient the diffusion of oxygen
• The mean life is about 120 days

9
Leucocytes (white cells) the defense of the
organism

• 4-10 .103 / mm3 4-10 .109 / l
• size 10 µm in diameter
• granulocytes (presence of granules in the
  cytoplasm) 70
• granules have a different affinity towards
  neutral, acid or basic stains and give the
  cytoplasm different colors.
• neutrophils
• eosinophils (or acidophils)
• basophils
• agranulocytes (lymphoid cells) 30
• lymphocytes (upper slide)
• monocytes (lower slide)

10
Thrombocytes (platelets)

• 150-300 .103 / mm3 150-300 .109 / l
• size 3µm in diameter
• They gemmate from big leukocytes called
  megakaryocytes.
• main function hematostasis
• to stop the loss of blood from wounds gt they
  aggregate and release factors which promote the
  blood coagulation
• serotonin - vasoconstriction
• fibrin - traps cells forms clotting

11
Hematopoiesis regulationin red bone marrowribs,
vertebrae, breastbone, pelvis
12
Erythropoietin is converted from a plasma
protein in the kidney

• a negative-feedback mechanism
• - is sensitive to the amont of O2 in the blood
• ? O2 gt ? erythropoietin
• ? O2 gt ? erythropoietin
• Erythropoietin
• stimulates production of erythrocytes in the
  bone marrow

13
Blood clotting

• 1) Platelet adhesion
• 2) Platelet plug
• 3) Fibrin clot with trapped cells

14
Blood clotting
15
Blood clotting

• Hemophilia
• X-linked disease
• missing -
• coagulation factor VIII
• symptoms
• spontaneous bleeding
• bleeding into organs (join, brain)

16
Literature

• Biology, eighth edition,
• Campbell, Reece
• Unit seven Animal Form and Function
• Chapter 42 Circulation and Gas Exchange
• Concept 42.4
• Pages 911 915