Exam 6: Energy and Metabolism

Many metabolic pathways are ultimately concerned with ATP; either with the generation of ATP,or with the requirement of ATP for that pathway to function.Why is ATP so important to metabolism?

A calorie is the commonly used unit of chemical energy.It is also the unit of

The Law of Thermodynamics that states that energy cannot be created or destroyed is:

Phosphofructokinase (PFK)is an enzyme that converts fructose 6-phosphate to fructose 1,6-bisphosphate,by adding a phosphate group.This is the first committed step of the metabolic pathway of glycolysis,and thus it is very tightly regulated.AMP binds to PFK at a site distinct from the binding site for fructose 6-phosphate,and stimulates the formation of fructose 1,6-bisphosphate.ATP binds to PFK at a site distinct from the binding site for fructose 6-phosphate,and inhibits the formation of fructose 1,6-bisphosphate.There are other regulators of this enzyme as well.What is the role of AMP in this example?

A particular reaction has a negative delta G.However,this reaction takes many years to proceed in the absence of enzyme.Why is this the case?

The synthesis of sugar molecules through the process of photosynthesis requires energy absorbed from sunlight.Bearing this in mind,what kind of reaction is photosynthesis?

Why do we have storage macromolecules,such as fats,in our bodies?

The term oxidation is derived from the name of the element oxygen.This is reasonable,because oxygen

Glycolysis is a metabolic process that is conducted by nearly all cells.However,in addition to glycolysis,some cells also make use of another metabolic process called the Krebs cycle.What does this tell you about the evolution of these processes?

The ultimate source of energy for humans comes from what source?

When the substrate is bound to the enzyme,the shape of the enzyme may change slightly,leading to

For a particular chemical reaction,the enthalpy of the reactants is -400 kJ.The enthalpy of the products is -390 kJ.The entropy of the reactants is 0.2 kJ/K.The entropy of the products is 0.3 kJ/K.The temperature of the reaction is 25 degrees Celsius.What can you conclude about this reaction?

Metabolic reactions fall under two general categories: anabolic and catabolic.What type of chemical reactions are these two classes of metabolic reactions?

It is summer,and you are excited about going to your local amusement park,and specifically about riding the new roller coaster that was just built.You imagine waiting at the top of the stairs for the roller coaster to pull into the station,climbing into the car,strapping yourself into the seatbelt,and pulling down the harness.You can imagine the cars slowly chugging up to the top of the first hill,coming down on the other side,and the excitement you expect to feel as you go along for the ride.Of all of the things that you have imagined,which is an example of potential energy?

Glucose is converted into glucose 6-phosphate by hexokinase.Glucose 6-phosphate then serves as the substrate for the enzyme phosphoglucose isomerase,which converts this reactant into fructose 6-phosphate.Fructose 6-phosphate serves as the substrate for phosphofructokinase,which converts fructose 6-phosphate into fructose 1,6-bisphosphate.Based on the information provided,this is an example of what?

RNA molecules that also act as enzymes are given the name

You return home to find that your baby brother has scattered his toy trains and trucks all over the floor of your room.As you begin to pick up the toys and put them away,you realize that even though he is just a baby,he has clearly mastered:

You eat a bowl of beans as part of your dinner.As you digest the beans,the proteins that are present get broken down to their component amino acids.As your body destroys the macromolecules that were present in the beans,is the energy present in those molecules destroyed?

The organic nonprotein components that aid in enzyme functioning are called

When an atom or molecule gains one or more electrons,it is said to be: