PHYSIOLOGY I
IMPORTANT VALUES FOR INTRODUCTION TO PHYSIOLOGY
COMPOSITION OF THE HUMAN BODY
The approximate composition of an average adult human per body weight is that
 Water
= 60%
 Proteins = 18%
 Fats
= 15%
 Minerals = 7%
Note that CHO do not have structural importance.
HOMEOSTATIC VALUES
1. Body fluid volume = 40 L
a. ECF = 15L
b. ICF = 25L
a. 12L of fluid in the ICF is interstitial fluid
2. Osmolality = 300 mosm/L, (285 – 300 mosm/L)
3. Body T. = 36.3 – 37.1OC
4. pH
= 7.35 – 7.45
5. Blood Gases
a. PCO2 = 35 – 45 mm Hg
b. PO2 = 40 – 104 mm Hg
6. Electrolytes (ECF)
a. Ca2+ =
10 mg/dL or 5 meq/L
b. K+
=
4 meq/L
c. Na+ =
142 meq/L
d. Cl- =
103 meq/L
e. HCO3=
27 meq/L
7. Plasma cholestrol level: 120-220 mg/dl
8. Waste Products
a. Bilirubin
=
0.5 mg/dl
b. Creatinine =
0.6 – 1.5 mg/dL
c. Blood urea nitrogen (BUN) = 8 – 25 mg/dL
d. Uric acid (s):
 Women = 2.3 – 6.6 mg/dL
 Men = 3.6 – 8.5 mg/dL
9. Plasma lactate = 0.5 – 2.2 meq/L
PHYSIOLOGY I
10.Blood Glucose level (fasting): 70 – 110 mg/dL or 80-120mg/dl
11.Arterial Blood pressure (systemic circulation).
a. Systolic pressure
= 120 mm Hg (90 – 140 mm Hg)
b. Diastolic pressure =
80 mm Hg (60 – 90 mm Hg)
c. Pulse pressure
=
40 mm Hg
d. Mean BP
=
96 mm Hg
e. Pulmonary AP
=
25/10 mm Hg
f. Cardiac output
=
5 L/min
g. Blood Flow =
5 L /min
12.RBC count
=
4-6 millions/mm3
13.WBC count
=
4000-11,000/mm3
14.Hemoglobin
=
12-18 g/dl in F, 14-20 g/dl in M
**Deviations in normal ranges
= pathology
PERCENT PROPORTION OF THE CELL’S PLASMA MEMBRANE:
1. Proteins = 55 %
2. Lipids = 42 %
a. Phospholipids = 25 %
b. Cholesterol = 13 %
c. Neutral fats = 4 %
3. Carbohydrate = 3 %
BODY FLUIDS
Concentration of Electrolytes in the ECF
• Na+
142 meq/L
• K+
4 meq/L
2
• Ca +
2.5 meq/L
• Mg2+ 1.2 meq/L
• Cl103 meq/L
• HCO328 meq/L
3
• PO4 - 4 meq/L
• SO42- 1 meq/L
• Glucose
90 mg/dl
• Aminoacids 30 mg/dl
• Lipid (C, P, NF) 0.5 gm/dl
PHYSIOLOGY I
• PO2
• PCO2
• pH
40 mm Hg
45 mm Hg
7.4
Concentration of Electrolytes in the ICF
 Na+ 10 meq/L
 K+ 140 meq/L
 Ca2+ 0.0001meq/L
 Mg2+ 58 meq/L
 Cl- 4 meq/L
 HCO3- 10 meq/L
 PO43- 75 meq/L
 SO42- meq/L
 Glucose 0 to 20 mg/dl
 Amino acide 200 mg/dl
 Lipid 2 – 95 gm/dl
 PO2 20 mm Hg
 PCO2 50 mm Hg
 pH 7.0
HOMEOSTASIS OF WATER
• To remain properly hydrated, water intake must equal water output
• Water intake sources
– Ingested fluid (60%) and solid food (30%)
– Metabolic water or water of oxidation (10%)
• Water output
– Urine (60%) and feces (4%)
– Insensible losses (28%), sweat (8%)
• Increases in plasma osmolality trigger thirst and release of antidiuretic
hormone (ADH)
PH OF DIFFERENT BODY FLUIDS
 Extracellular fluid
o Arterial blood = 7.4
PHYSIOLOGY I
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



o Venous blood = 7.35
Interstitial fluid = 7.35
Intracellular fluid = 7.0
Urine = 4.5 - 8.0
Gastric HCl = 0.8
Pancreatic juice = 8.0
CHARACTERISTICS OF BLOOD
• The pH of blood is 7.35–7.45 and its salt content is 0.9%
• Temperature is 38C, slightly higher than “normal” body temperature
• Blood accounts for approximately 8% of body weight
• Average volume of blood is 5–6 L for males, and 4–5 L for females
• Contains 55% plasma and 45% formed elements
Plasma: Liquid portion of blood
• It makes up 55% of the blood volume
• Has the osmolality of 300 mosm/l
• Composed of:
1. Water (90%)
2. Organic constituents (9%)
a. Plasma proteins (7%)
1. Albumin (4%)
2. Globulins (2.7%)
3. Fibrinogen (0.3%)
b. Lipids, lipoproteins, phospholipids
c. Hormones and enzymes
d. Nutrients: CHO, vitamines, amino acids, fats
e. Metabolic waste products: urea, creatinine
3. Inorganic constituents: electrolytes (1%)
4. Respiratory gases – oxygen and carbon dioxide
PHYSIOLOGY I
RED BLOOD CELLS
• Major content of RBCs is Hb (97% )
• Size:
• Diameter 7.5 µm
• Thickness 1 and 2 µm
• RBC Count
• Male = 5.2 millions/mm3
• F = 4.6 millions/mm3
• Filled with hemoglobin Hb = 1/3 Hct
Hematocrit values:
• Men 42 – 48%
• Women 38 – 43%
• Children 35 – 42%
HEMATOPOEISIS
• Begins in early embryonic life and continues
throughout life
• Yolk sac = 3rd to 10th Week
• Liver = 6th to 32nd Week
• Spleen = 10th to 25th Week
• Bone marrow
30th to 36th Week and also after birth
RED BLOOD CELL (RBC) INDICES
 Mean corpuscular volume (MCV) = 80 – 100 femtoliter fL
 Mean corpuscular hemoglobin (MCH) = 26 – 32 picograms pg
 Mean corpuscular hemoglobin concentration (MCHC)
o Normo chromic cells 32 - 36 g/dL.
o Hypo chromic cells <32 g/dl.
o Hyper chromic cells are >37g/dl.
HEMOGLOBIN
• Males: 14-18 gm/100ml blood
• Females: 12-16 gm/100 ml blood
PHYSIOLOGY I
IRON METABOLISM
Iron exists in the body in different forms
 65% in the form of Hb
 4% in the form of Mb
 1% in the form of cytochromes
 0.1% in combination with transferin
 15-30% stored in the liver in the form of ferretin and
ANEMIA
Hb 10-11.9 g/dl = mild anemia
7- 9.9 g/dl = moderate anemia
<7g/dl = severe anemia that needs blood transfusion
WHITE BLOOD CELLS (WBCs)
 Make up 1% of the total blood volume
 Normal WBC count: 4000 – 11000/mm3
o Average: 7000/mm3
WBC differential count
 Neutrophils:
 Eosinophils:
 Basophils:
 Monocytes:
 Lymphocytes:
50-60% (60%), 3000-7000/mm3
1-4% (2.4%), 100-440/mm3
0.3-0.5% (0.4%), 20-50/mm3
2-8% (5.3%), 100-700/mm3
20-40% (30%), 1500-3500/mm3
hemosiderin