BIOCHEMISTRY - Main Regulators and Biological Fluids of the Human Body - 2016

5. BLOOD BIOCHEMISTRY

5.3. Chemical Composition of Blood

The Chemical composition of Blood is kept relatively constant, and any deviations are quickly corrected. The organic components of blood are listed in Table 6.

Class="center">Table 6

Organic Constituents of Blood

Parameter

Whole blood

Plasma

Erythrocytes

Volume, %

100

54 - 59

41 - 16

Water, %

75 - 85

90 - 91

57 - 68

Dry residue, %

15 - 25

9 - 10

32 - 13

Hemoglobin, %

13 - 16

-

30 - 11

Total protein, %

-

6.5 - 8.5

-

Fibrinogen, %

-

0.2 - 0.4

-

Globulins, %

-

2.3 - 3.0

-

Albumins, %

-

4.0 - 5.0

-

Non-protein nitrogen, mg %

25 - 35

20 - 30

30 - 10

Glutathione, mg %

35 - 45

Traces

75 - 120

Urea, mg %

20 - 30

20 - 30

20 - 30

Uric acid, mg %

3 - 4

4 - 5

2 - 3

Creatinine, mg %

1 - 2

1 - 2

1 - 2

Creatine, mg %

3 - 5

1 - 1.5

6 - 10

Amino Acid Nitrogen, mg %

6 - 8

5 - 6

8

Glucose, mg %

80 - 110

80 - 120

60 - 70

Lipids, mg %

380

400 - 700

170

Neutral fats, mg %

-

100 - 250

-

Total Cholesterol, mg %

150 - 200

150 - 250

150

Lecithins, mg %

200

100 - 200

350

Ketone Bodies, mg %

-

0.8 - 5

-

Pyruvic acid, mg %

-

0.8 - 1.2

-

Lactic acid at rest, mg %

-

15 - 20

-

Lactic acid under load, mg %

-

up to 250

-

The concentrations of several substances in venous and arterial blood are not identical. For instance, the concentration of glucose is higher in arterial blood, whereas the concentrations of lactic acid and pyruvic acid are lower than in venous blood, because Muscles absorb glucose and release its breakdown products.

5.3.1. Blood Proteins

Erythrocytes contain hemoglobin, while plasma contains albumins, globulins (which differ in charge and molecular weight), and fibrinogen. During muscular activity, the concentration of albumin increases, whereas during severe fatigue it decreases, while The amount of globulins, conversely, rises. Similar changes occur during biological Aging.

In addition, the blood contains intrinsic blood Enzymes (such as erythrocyte catalase) or enzymes entering the bloodstream from other Tissues. During intense muscular work, the amount of enzymes increases (hyperenzymemia develops). Excess enzymes are cleared by the Liver during periods of rest.

5.3.2. Non-Protein Nitrogen of Blood

Blood non-protein nitrogen is represented by nitrogen-containing non-protein substances (namely urea, uric acid, creatine, creatinine, and ammonium salts). During muscular activity, the level of blood non-protein nitrogen rises, and in Renal Dysfunction, it can increase 5- to 10-fold.

5.3.3. Mineral Constituents of Blood

Mineral Substances in Blood Plasma exist in the form of ions. Blood plasma contains the highest amounts of sodium, potassium, chlorides, and bicarbonates (Table 7).

Table 7

Mineral Composition of Blood

Ions

Plasma content, mg %

Erythrocyte content, mg %

Nа+

300 - 500

50 - 100

К+

15 - 20

450 - 180

Fе3+

Traces

In hemoglobin

СI-

370

200

НСО-3

200

-

РО3-4

5

In Organic compounds

Abnormalities in the mineral composition of blood plasma are observed in various diseases and during water loss caused by excessive sweating resulting from, for example, physical exertion.



Last update: 06/08/2026

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