Chemical Aspects in Physiology


    • Have you ever heard your mother say "You need your protein!" Well, this is why. Enzymes are proteins that catalyze (increase or decrease the rates of) chemical reactions. There is a specific enzyme for each chemical reaction. When I think of protein synthesis, I often think of certain puzzle pieces fitting together. Substrates are the reactact molecules. They fit into the active sites of their specific enzyme which forms a enzyme-substrate complex. This complex dissociates, releasing the products of the reaction and the new enzyme. Enzymes play an important part of physiology serving a wide variety of functions in the human body. Cells use enzymes to grow, reproduce, and create energy and are vital in order for a human to live.
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=Above is a diagram outlining amino acids to proteins.
proteins.jpg
If you have learned anything about enzymes, it should be...EAT YOUR MEAT! : )









    • The pH SCALE is a chemical scale that measures how acidic or basic a substance is. The scale ranges from 0-14 with 7 being neutral. (Water is 7 on the PH scale). Normal body PH in a human being is 7.35-7.45.
    • ACIDS have a pH level of less than 7. Acidic substances release hydrogen ions in a solution. An increase in hydrogen ion concentration decreases the pH of a soluation and leads to acidity.
    • BASES have a pH level greater than 7. Bases lower hydrogen ions in a solution and decrease the concentration, leading to an increase in pH and making the solution more basic or alkaline.




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Acid/base imbalances occur when a significant change causes the blood pH to shift out of it's normal range (that being 7.35-7.45). The acid/base system is tightly regulated by buffers, which maintain pH. Buffers are systems of ions and molecules that act to prevent changes in the hydrogen ion concentration of a solution. Examples of buffers in the body are carbonic acid-bicarbonate, intracellular and plasma protein, and hemoglobin buffers. pH is stabilized in the blood by a reversible reaction between bicarbonate and carbonic acid.

=Types of Acid Base Imbalances

Respiratory Acidosis- decreased pH, carbonic acid excess

Examples of causes: Pneumonia, Emphysema

Respiratory Alkalosis- increased pH, carbonic acid deficit

Examples of causes: Hyperventilation, anxiety
=´╗┐Metabolic Acidosis- decreased pH, bicarbonate deficit.

Examples of causes: Poorly managed diabetes, excessive alcohol use

Metabolic Alkalosis- increased pH, bicarbonate excess


Examples of causes: Prolonged vomiting causing loss of acid, excessive indigestion of antacids.


*QUESTION: Describe buffers, their importance, and the buffering system (bicarbonate/carbonic acid) used in the blood to
regulate the narrow range of pH in the blood. What is the difference between acidosis and alkalosis? As briefly described above, pH is a tightly regulated system. Buffers are systems of ions and molecules that act to prevent changes in the hydrogen ion concentration of a solution (pH).

Examples of buffers in the body are carbonic acid-bicarbonate, intracellular and plasma protein, and hemoglobin buffers.

pH is stabilized in the blood by a reversible reaction between bicarbonate and carbonic acid.

HCO3- + (H+) <---> H2CO3

Alkalosis is when there is a deficiency of acids in the body and/or too much base. Directly the opposite is acidosis, resulting from an over abundance of acids in the blood/body and a low amount of base.