bio test #2 ferrante questions
Which pH value indicates the most basic solution?
11
How many total moles of KNO3 must be dissolved in water to make 1.5 liters of a 2.0 M aqueous solution?
3.0 moles
A 3.0 M aqueous HCl solution contains a total of
3.0 moles of HCl per liter of solution
The pH of the internal environment of lysosomes (organelles that contain digestive enzymes) is approximately 4.5, while the pH of the surrounding cytoplasm is approximately 7. The average pH of the human stomach during digestion is approximately 2.5, while the average pH of the small intestine during digestion is about 8. The graph below shows how pH affects the enzyme activity of four different enzymes, A, B, C, and D. Which enzyme functions best in a pH environment most similar to that of human stomach enzymes?
A
Many hormones are proteins used in calculate communication. Each hormone carries a specific message to specific target cells. State why each of these hormones is able to deliver a different message.
Each hormone has a specific shape that enables it to interact with a specifically shaped receptor. (Lock and key/model)
Based on the investigation, the student should conclude that enzymes
Function best within a specific range of conditions
Which statement explains the importance of maintaining a constant internal environment to ensure proper enzyme functioning?
Increasing the temperature and pH can alter the specific shape of enzymes.
The pH of the internal environment of lysosomes (organelles that contain digestive enzymes) is approximately 4.5, while the pH of the surrounding cytoplasm is approximately 7. The average pH of the human stomach during digestion is approximately 2.5, while the average pH of the small intestine during digestion is about 8. The graph below shows how pH affects the enzyme activity of four different enzymes, A, B, C, and D. What will most likely happen to the action of an enzyme from the small intestine if it is placed in an environment similar to the environment in which enzyme C functions best?
It would be able to function because the pH of the environment is similar to that of the intestine.
Some carbonated beverages are made by forcing carbon dioxide gas into a beverage solution. When a bottle of one kind of carbonated beverage is first opened, the beverage has a pH value of 3. State, in terms of the pH scale, why this beverage is classified as acidic.
It's pH is 3 which is lower than 7
Base your answers to the question on the diagram below, which represents a chemical reaction that occurs in the human body, and on your knowledge of biology.
Molecule Z will function best at a specific pH.
An enzyme was isolated from digestive juices taken from the small intestine. An experiment was set up to test the ability of the enzyme to break down protein. Two test tubes, labeled A and B, were placed in a hot water bath at 37 degrees C, human body temperature. Test tube A contained only protein and test tube B contained protein and the enzyme. The chart below shows the set-up. After two hours, the contents of both test tubes were analyzed. Test tube A showed only the presence of end products of protein digestion, indicating the enzyme had successfully broken down the protein. State what the result would be if the same enzyme that was added to test tube B was added to a test tube containing starch.
Nothing happens; Low digestion
A fully functioning enzyme molecule is arranged in a complex three- dimensional shape. This shape determines the
Specific type of molecule it interacts with during a reaction.
Explain the importance of temperature in the functioning of enzymes.
Temperature affects the shape of an enzyme+ therefore it's function.
Which statement is supported by the information in the graph below?
The enzymes respond in a similar way to changes in temperature.
The pH of the internal environment of lysosomes (organelles that contain digestive enzymes) is approximately 4.5, while the pH of the surrounding cytoplasm is approximately 7. The average pH of the human stomach during digestion is approximately 2.5, while the average pH of the small intestine during digestion is about 8. The graph below shows how pH affects the enzyme activity of four different enzymes, A, B, C, and D. Lysosomes break open during the process of digestion, releasing enzymes into the cytoplasm. Which statement may explain why the entire cell may not be digested?
The pH of the cytoplasm causes the enzymes to function less effectively.
Which statement best describes enzymes?
The rate of activity of an enzyme might change as pH changes.
The molecules represented in the diagram below can interact to cause a biochemical process to occur. Molecule A and molecule B most likely represent
a receptor and a hormone
The basic building blocks of a protein are
amino acids
Shrimp that live in the cold waters off Alaska will die if introduced into warm water. One likely reason these shrimp do not survive is that enzymes in the shrimp
change of shape
One effect of uncontrolled diabetes is that the blood might develop an acidic pH. As a result, cells may not be able to regulate their internal pH. Within these cells, this could cause a disruption of the function of biological catalysts known as
enzymes
The process of transferring energy during respiration occurs in a series of steps. This prevents too much heat from being released at one time. Maintaining an appropriate temperature is beneficial to an organism because
enzymes need a proper range of temperatures to catalyze vital reactions
The way a protein molecule is folded determines the shape of the molecule, which determines the
function of that protein
The shape of a protein molecule directly determines its
functions inside and outside of cells
The pH of an aqueous solution changes from 4 to 3 when the hydrogen ion concentration in the solution is
increased by a factor of 10
The least pH it has the
more acidic it is
A student wants to test the hypothesis that an acidic environment will decrease enzyme activity. In the experiment, the student used an enzyme that breaks down hydrogen peroxide into water and bubbles of oxygen. To test the hypothesis, the student should collect data on the number of oxygen bubbles produced at differen
pH levels
The function of a specific enzyme is most directly influenced by its
physical shape
The shape of each of the molecules is important because
the shape of a molecule determines how it functions in chemical reactions
The graph below represents the effect of pH on three different enzymes at normal body temperature. The graph illustrates that enzymes 1, 2, and 3 (June 2015)
work best at different pH levels
