5 Written questions
5 Matching questions
- While eating a container of yogurt, you have to leave, so you store the yogurt in the refrigerator. A day later you return and find the surface of the yogurt is no longer smooth but has broken into several liquified products. You correctly guess that enzymes from your saliva, via the spoon, have continued digesting the yogurt in your absence. What will happen over time?
A. The reaction will soon stop because the amount of saliva is small, and you would have to add more saliva to continue the degradation.
B. The reaction will continue, since the enzyme is not consumed by the reaction.
C. The reaction will continue until half is digested and then stop because the reaction between substrate and product will be balanced.
D. Absolutely no degradation of the yogurt will occur naturally unless in the presence of this enzyme.
- Which organelles contain functioning ATP synthetase complexes in their membranes?
A. Golgi complexes and lysosomes.
B. Mitochondria and chloroplasts.
C. Endoplasmic reticulum and vesicles.
D. Vacuoles and vesicles.
E. Mitochondria and endoplasmic reticulum.
- The activity of an enzyme might be increased by all of the following except ________?
A. increase in substrate concentration.
B. a vitamin.
C. 2-4 degree increase in temperature.
Identify the graph that depicts the reaction C→D.
- Lactose is milk sugar, and humans produce substantial lactase enzyme to digest it when we are infants. However, we soon lose some or even all of our lactase after childhood. In such cases, undigested lactose passes to the lower intestine where bacteria break it down into lactic acid and CO2, causing painful gas bloating. This problem could be avoided by
A. avoiding all dairy products containing lactose.
B. taking lactase enzyme tablets when consuming lactose products.
C. taking any enzyme tablets when consuming dairy products.
D. consuming lactose in tablet form.
E. Both taking lactase enzyme and avoiding all dairy products would be correct.
- a B. Mitochondria and chloroplasts.
- b D. lead.
- c E. Both taking lactase enzyme and avoiding all dairy products would be correct.
- d B. The reaction will continue, since the enzyme is not consumed by the reaction.
- e B.http://www.flickr.com/photos/60296733@N06/5514033968/
5 Multiple choice questions
- D. All of the choices are correct.
- D. As the substrate binds to the enzyme, the shape of the active site changes to accommodate the reaction.
- E. are about twelve enzymes, at least one responsible for each step in the metabolic pathway.
- D. addition of distilled water
5 True/False questions
Which of these statements is NOT a consequence of the second law of thermodynamics?
A. While the total amount of energy is unchanged, the energy lost as heat is no longer useful to the cell in doing work.
B. Reactions that occur spontaneously are those that increase the amount of useful energy in a system.
C. The amount of disorder in the universe is always increasing.
D. To maintain organization of a cell, a continual input of energy is required. → B. Reactions that occur spontaneously are those that increase the amount of useful energy in a system.
Which of the following is NOT a form of potential energy?
B. water in a dam
C. a muscle contracting
D. All of the choices are not potential energy. → C. Eventually sunlight that is absorbed on the earth returns to space as dispersed heat.
Which statement is NOT true about enzyme inhibition?
A. In competitive inhibition, the inhibitor binds to the active site of the enzyme.
B. In noncompetitive inhibition, the inhibitor binds to the allosteric site of the substrate.
C. In irreversible inhibition, a poison binds to the enzyme so that it can never work again.
D. Most inhibitors act in a reversible fashion.
E. All of the statements are true. → D. An enzyme's activity is generally reduced by an increase in substrate concentration.
In the electron transport systems of chloroplasts and mitrochondria,
A. the system consists of a series of membrane bound carriers that transfer electrons from one carrier to another.
B. high energy electrons enter the system and low energy electrons exit the system.
C. energy release occurs when the electron transfers from one carrier to another.
D. All of the choices are correct. → D. addition of distilled water
If the reaction graphed at right is coupled with D→E, then D →E is:
D. none of the above → B. endergonic