Term
Water Content:
In adults?
Children?
Men vs. Women?
Young vs. Old?
Obese people? |
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Definition
Water content is adults ~50%-60%
~75% in children
Water content tends to be higher in women, as well as in younger people.
Water content tends to be lower in obese peopl due to higher body fat content (lipids and water dont mix!) |
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Term
| Functions of water inside the body |
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Definition
* Bathes our cells
* dissolves and transports compounds in the blood
*dissipates heat, and participates in chemical reactions. |
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Term
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Definition
| A weak and noncovalent bond between hydrogen and a more electronegative atom (in this case- oxygen) |
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Term
| How many hydrogen bonds can a water molecule have? |
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Definition
| 4 bonds. These bonds are not static and thus, do not last long (pico seconds) |
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Term
Water as a solvent:
How does hydrogen interact? |
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Definition
Hydrogen interacts with organicmolecules (O/N).
Hydrogen also interacts with inorganic salts (Cl-),
(HCO3-), and other anions
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Term
| What is the purpose of electrolytes? |
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Definition
Electrolytes maintain volume in the cell to make sure it stay isotonic; very important to maintain constant electrolyre balance.
Constant electrolytes keep you hydrated (during exercise, drinking, etc) |
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Term
| Electrolytes in the ECF and ICF |
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Definition
In the ECF: Na+ and Cl-
In the ICF: K+ and phosphates |
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Term
| What maintains the electrolytic difference along cell membranes? |
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Definition
| The Na-K Pump: an energy requiring transporter that pumps 3 Na+ out of the cell for every 2 K+ pumped back in. This helps maintain homeostasis |
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Term
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Definition
total concentration of all dissolved molecules, including ions, metabolites, and proteins.
Units are in milliosmoles (mOsm/ kg water) |
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Term
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Definition
| An acid donates H+ to a solution and will have pH lower than 7 |
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Term
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Definition
| A base accepts H+ and has pH above 7 |
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Term
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Definition
undissociated acid that still has lots of H+ to give away.
Will usually end in "-ic acid" examples are sulfuric acid and gastric acid (gastric acid is the strongest one found in the body!)
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Term
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Definition
Dissociated acids, will only PARTIALLY give away H+, most acids in the body are weak acids.
Examples: Lactic acid (anaerobic glycolysis) and Carbonic Acid (TCA cycle) |
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Term
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Definition
- solution's tendency to disocciate a proton
- The lower the pKa, the stronger the acid |
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Term
| Henderson Hasselbach Equation |
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Definition
If the pKa of an acid is known, this eqn can calculate the ratio of unprotonated to protonated solution
pH= pKa + log (A-/ HA) |
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Term
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Definition
| A weak acid and its conjugate base. This makes a solution that will resist change in pH when H or OH ions are added. |
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Term
| What is the optimal pH for a buffer? |
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Definition
| ~1 pH unit of is pK. This compensates for any inlux or removal of H+ ions. |
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Term
| How do you increase the capacity of a buffer? |
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Definition
| By adding more concentrated buffers! |
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Term
| Metabolic Acid & Bicarbonate |
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Definition
Bicarbonate serves as a buffering system for the body to keep internal pH in a very tight range! Otherwise, the accumulation of metabolic acid would drop pH down to ~1
Bicarbonate system is at pH 4.76 when pH=pKa |
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Term
| Widest range of extracellular pH? |
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Definition
pH= 6.8-7.8
this tight pH regulation is held by major body buffer systems! |
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Term
| What are the 4 buffer systems in the body? |
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Definition
1. Bicarbonate- ECF
2. Hemoglobin- RBCs
3. Phosphate- all cell types
4. Proteins- cells and plasma |
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Term
Bicarbonate Buffer System
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Definition
| Bicarbonate will combine with H+ to form Carbonic acid. through carbonic anhydrase, this acid is broken down into CO2 and H2O |
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Term
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Definition
In RBCs
H+ is buffered by Hb and phosphate |
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Term
| What neutralizes HCl from parietal cells in the stomach? |
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Definition
| Bicarbonate that is secreted by pancreatic cells and cells lining the intestine will neutralize pH so the acidity does not cause the intestinal lining to rupture |
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Term
| Body Buffer Systems Working Together |
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Definition
1. CO2 from cellular metabolism will make bicarbonate, which is then transported into blood to buffer H+ from other metabolic acids (ex: acetoacetic acid)
2. Inside RBCs, H+ is buffered by phosphate and Hb. |
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