I believe the second answer is correct.
Answer:
Birds, like mammals, have a 4-chambered heart (2 atria & 2 ventricles), with complete separation of oxygenated and de-oxygenated blood. The right ventricle pumps blood to the lungs, while the left ventricle pumps blood to the rest of the body.
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<u>PLEASE</u><u> MARK</u><u> ME</u><u> BRAINLIEST</u></h3>
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Answer:
A. pH
Explanation:
Denaturation of proteins is a protein whereby the protein molecule loses its primary structure and ultimately its physical functioning as a result of factors including pH, temperature or concentration of chemicals. Based on this definition, it is visible that denaturation of proteins can be caused by these three factors: pH, chemical and temperature.
However, in this case of PEPSIN enzyme, which is a proteinous molecule produced in the stomach of humans and functions in breaking down proteins, its denaturation occurs as it moves along the digestive tract to the intestines. This is as a result of the changes in pH in the digestive tract.
The pH of the stomach where pepsin is produced is acidic i.e. <3.0. However, as one moves towards the intestine, the pH increases, which is unfavorable or considered harsh for the pepsin enzyme. Hence, it gets denatured.
When humans and other animals lack sufficient oxygen, they'll create ATP through a form of anaerobic respiration that produces lactic acid as a byproduct. ... Yes 'Anaerobic' means 'without oxygen. Cells will produce ATP through lactic acid fermentation only under when they lack sufficient oxygen.