Question

enzymes and cellular regulation
what are the factors that regulate the rate at which enzymes catalyze reactions?
why?
digestive enzymes are protein - based biological catalysts that play important roles in our lives. they help remove stains from our shirts, turn milk into cheese, and are responsible for turning our dinner into use - able fuel for our bodies. enzymes however do not work well universally. some are meant to work at high temperatures, others at low temperatures. they may work best in acidic conditions or neutral conditions.
in this activity we will look at the optimal conditions for two different enzymes. the digestive enzyme lipase is made in the pancreas and breaks down lipids in the small intestine, while pepsin breaks down proteins in the stomach.
model 1 - two digestive enzymes
lipase
triglycerides → glycerol + fatty acids
pepsin
large polypeptides → smaller polypeptides + amino acids
effect of ph on enzyme activity

1. name the two enzymes illustrated in model 1.
2. consider the information provided in the why? box and in model 1 about these proteins.

a. in which body organ is pepsin active?
b. in which body organ is pancreatic lipase active?
enzymes and cellular regulation
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Explanation:

1. The text in Model 1 clearly shows the two enzymes: lipase and pepsin.
2. a. The "Why?" box states that pepsin breaks down proteins in the stomach.

b. The "Why?" box mentions that lipase is made in the pancreas and breaks down lipids in the small intestine.

Answer:

1. Lipase and pepsin.
2. a. Stomach.

b. Small intestine.