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Which curve(s) on the graphs may represent the temperature and pH profiles of enzymes taken from a bacterium that lives in a mildly basic hot springs at temperatures of 70 degrees Celsius or higher?

A series of enzymes catalyze the reaction X –> Y –> Z –> A.  Product A binds to the enzyme that converts X to Y at a position remote from its active site.  This binding decreases the activity of the enzyme.  What is substance X?

The figure above represents a rough endoplasmic reticulum. Which of the following best describes the role of the structure labeled Y?

Which of the following is TRUE of the structure shown below:

A substance that releases hydrogen ions (H+) in solution is known as:

Which of the following terms describes a molecule that is attracted to water?

In a laboratory experiment using spectrophotometry, an enzyme is combined with its substrate at time zero.  The absorbance of the resulting solution is measured at time zero and at five-minute intervals.  In this procedure, an increase in absorbance is related to the amount of product formed during the reaction.  The experiment is conducted using the three preparations shown in the table below. Absorbance of Solution at different times Enzyme Preparation 0 min 5 min 10 min 15 min 20 min I.    3 mL of enzyme preparation    2 mL of substrate   pH 5.0 0.0 0.22 0.33 0.38 0.37 II.    3 mL of boiled enzyme preparation      2 mL of substrate      pH 5.0 0.0 0.06 0.04 0.03 0.04 What is the constant (standardized) variable of this experiment? Check all that apply.

If a substance has a pH of 6, it is considered …

The diagram above represents a typical rod-shaped bacterium. Which of the following best describes a feature shown in the diagram that is unique to bacteria?

If the shape of an enzyme’s active site is altered, it can result in: