PH is a scale from 0-14 used to determine if substances or mediums are acidic, alkaline or neutral. Blood is a buffer solution with a PH of 7.4, and it resists change in PH as it contains week conjugate acid and base pair; carbonate HCO3- and carbonic acid H2CO3. Mediums and solutions can be either acidic, alkaline or neutral; acidic if their measured PH is less than 7, neutral if their measured PH is 7, and alkaline if their measured PH is greater than 7. An organ can be made of different types of tissues that combine to form an organ. An organ system or a biological system is when two or more organs work together in execution of a body function. Reproductive organs in men or women are organs involved in the producing of children and involved in sexual function. The series of hollow organs joined in a long tube from mouth to anus is the GI tract. Biological fluids are Liquids within living organisms; each has a distinct physiological role. These fluids can be either extracellular or intracellular. The objective is to determine and list the PH of some internal human organs and their biological fluids based on their acidity or alkalinity. The PH of some internal human organs is listed in Table 1 and the PH of some biological fluids are listed in Table 2.
| Published in | American Journal of BioScience (Volume 14, Issue 4) |
| DOI | 10.11648/j.ajbio.20261404.11 |
| Page(s) | 89-95 |
| Creative Commons |
This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited. |
| Copyright |
Copyright © The Author(s), 2026. Published by Science Publishing Group |
Chemistry, PH gradient, Internal Organs’ PH
Organ Type | PH | Acidic / Basic / Neutral |
|---|---|---|
Bone 33 | 7.4 | Mildly Alkaline |
Skin 5 | 4-6.5 | Weakly Acidic to Mildly Acidic |
Stomach 40,41 | 1.5-3.5 | Strongly Acidic |
Large intestine (Colon) 35, 39,40 | 7.9-8.5 | Mildly Alkaline |
Small intestine 3,39,40 | 7.2-7.5 | Mildly Alkaline |
Rectum 3,39,40 | 6.6-7.5 | Mildly Acidic to Mildly Alkaline. |
Bladder-Gallbladder bile 33 | 6.8 to 7.65 | Mildly Acidic to Mildly Alkaline. |
Liver 33 | 7-7.2 | Neutral to Mildly Alkaline. |
Heart 33 | 7-7.4 | Neutral to Mildly Alkaline. |
Brain 33 | 7.1-7.2 | Mildly Alkaline |
Pancreas and Pancreatic Secretion 33 | 7.5-8 | Mildly Alkaline |
Thyroid Gland | ||
Intrafollicular pH-PH of storage area of thyroid hormone 36 | 7.6 | Mildly Alkaline |
Intracellular pH- Thyroid follicular cells 36 | 6.94-7.01 | Mildly Acidic to Mildly Alkaline. |
Male Reproductive System | ||
Seminal vesicle gland fluid 32,38 | 7.2-8.5 | Mildly Alkaline |
Prostate fluid 32, 38 | 6.6-7.3 | Mildly Acidic to Mildly Alkaline |
Sperm 32,38 | 6.5 to 6.9 | Mildly Acidic |
Liquified semen fluid 32,38 | 7.2-8 | Mildly Alkaline. |
Female Reproductive system | ||
Uterine Cavity 6, 30, 31,34,37 | 6.76 to 7.8 | Mildly Acidic to Mildly Alkaline. |
Upper Vagina 6, 30, 31,34,37 | 5.7 | Moderately Acidic |
Lower Vagina 6, 31,34,37 | 3.8 to 4.5 | Weakly Acidic |
Vaginal PH 6, 31,34,37 | 3.5- 4.5 | Weakly Acidic. |
Fluid Type | PH Value | Acidic/ Basic/ Neutral |
|---|---|---|
Cerebrospinal Fluid | 7.3-7.36 | Mildly Alkaline |
Blood | 7.35-7.45 | Mildly Alkaline |
Stool | 6.5- 7.5 | Mildly Acidic to Mildly Alkaline |
Urine | 4.5-8 | Weakly Acidic to Mildly Alkaline. |
Pancreatic Secretion | 7.5-8 | Mildly Alkaline |
Seminal vesicle gland fluid | 7.2-8.5 | Mildly Alkaline |
Prostate fluid | 6.6-7.3 | Mildly Acidic to Mildly Alkaline. |
Sperm | 6.5 to 6.9 | Mildly Acidic |
Liquified semen fluid | 7.2-8 | Mildly Alkaline |
Gallbladder bile | 6.8 to 7.65 | Mildly Acidic to Mildly Alkaline. |
Saliva | 6.5-7.5 | Mildly Acidic to Mildly Alkaline. |
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APA Style
Abdel-Wahab, H., Gund, T., Bozzelli, J. (2026). The Chemistry of Some Internal Human Organs and Its Biological Fluids. American Journal of BioScience, 14(4), 89-95. https://doi.org/10.11648/j.ajbio.20261404.11
ACS Style
Abdel-Wahab, H.; Gund, T.; Bozzelli, J. The Chemistry of Some Internal Human Organs and Its Biological Fluids. Am. J. BioScience 2026, 14(4), 89-95. doi: 10.11648/j.ajbio.20261404.11
@article{10.11648/j.ajbio.20261404.11,
author = {Hebah Abdel-Wahab and Tamara Gund and Joseph Bozzelli},
title = {The Chemistry of Some Internal Human Organs and Its Biological Fluids},
journal = {American Journal of BioScience},
volume = {14},
number = {4},
pages = {89-95},
doi = {10.11648/j.ajbio.20261404.11},
url = {https://doi.org/10.11648/j.ajbio.20261404.11},
eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajbio.20261404.11},
abstract = {PH is a scale from 0-14 used to determine if substances or mediums are acidic, alkaline or neutral. Blood is a buffer solution with a PH of 7.4, and it resists change in PH as it contains week conjugate acid and base pair; carbonate HCO3- and carbonic acid H2CO3. Mediums and solutions can be either acidic, alkaline or neutral; acidic if their measured PH is less than 7, neutral if their measured PH is 7, and alkaline if their measured PH is greater than 7. An organ can be made of different types of tissues that combine to form an organ. An organ system or a biological system is when two or more organs work together in execution of a body function. Reproductive organs in men or women are organs involved in the producing of children and involved in sexual function. The series of hollow organs joined in a long tube from mouth to anus is the GI tract. Biological fluids are Liquids within living organisms; each has a distinct physiological role. These fluids can be either extracellular or intracellular. The objective is to determine and list the PH of some internal human organs and their biological fluids based on their acidity or alkalinity. The PH of some internal human organs is listed in Table 1 and the PH of some biological fluids are listed in Table 2.},
year = {2026}
}
TY - JOUR T1 - The Chemistry of Some Internal Human Organs and Its Biological Fluids AU - Hebah Abdel-Wahab AU - Tamara Gund AU - Joseph Bozzelli Y1 - 2026/08/18 PY - 2026 N1 - https://doi.org/10.11648/j.ajbio.20261404.11 DO - 10.11648/j.ajbio.20261404.11 T2 - American Journal of BioScience JF - American Journal of BioScience JO - American Journal of BioScience SP - 89 EP - 95 PB - Science Publishing Group SN - 2330-0167 UR - https://doi.org/10.11648/j.ajbio.20261404.11 AB - PH is a scale from 0-14 used to determine if substances or mediums are acidic, alkaline or neutral. Blood is a buffer solution with a PH of 7.4, and it resists change in PH as it contains week conjugate acid and base pair; carbonate HCO3- and carbonic acid H2CO3. Mediums and solutions can be either acidic, alkaline or neutral; acidic if their measured PH is less than 7, neutral if their measured PH is 7, and alkaline if their measured PH is greater than 7. An organ can be made of different types of tissues that combine to form an organ. An organ system or a biological system is when two or more organs work together in execution of a body function. Reproductive organs in men or women are organs involved in the producing of children and involved in sexual function. The series of hollow organs joined in a long tube from mouth to anus is the GI tract. Biological fluids are Liquids within living organisms; each has a distinct physiological role. These fluids can be either extracellular or intracellular. The objective is to determine and list the PH of some internal human organs and their biological fluids based on their acidity or alkalinity. The PH of some internal human organs is listed in Table 1 and the PH of some biological fluids are listed in Table 2. VL - 14 IS - 4 ER -