ATP is an energy carrier. Where is the energy actually located?
in the bonds between phosphate groups
The enzyme amylase in human saliva breaks starch polymers down into smaller sugar units. However, it cannot break down cellulose polymers. Both are made of glucose monomers, but in cellulose the monomers are linked together in a different shape than starch. Why can't amylase digest cellulose?
The bonds of cellulose do not fit properly in the active site.
Outside the body, sugar can catch fire and burn in an exergonic reaction. Inside the body, we also talk about burning sugar in an exergonic reaction, but it never catches fire. Why not?
When sugar is lit on fire, all of the bonds are broken at once. When the body breaks down sugar, enzymes break down one bond at a time.
All of the following statements pertaining to catalysts are true EXCEPT:
catalysts increase activation energy requirements.
Which of these statements regarding enzymes is FALSE?
Enzymes provide energy for the reactions they catalyze.
Animals have enzymes that break apart starch molecules but not cellulose, despite the fact that both are made up of glucose subunits. Which enzyme characteristic BEST explains this?
Enzymes are highly specific.
Most enzymes do not work if the temperature is raised too much. Why is this?
Enzymes denature at higher temperatures.
Why do chloroplasts make energy carriers during the light reactions?
to provide energy for the synthesis of sugar
The pigment(s) that absorb light energy to drive photosynthesis is/are:
chlorophyll and carotenoids.
The energy of the movement of electrons down a concentration gradient via electron transport within chloroplasts and mitochondria is used to generate molecules of:
Suppose you are studying photosynthesis in a research lab. You grow your plants in a chamber with a source of water that has a radioactively labeled oxygen atom. What photosynthetic product will be radioactive?
In the Calvin cycle, how many ATP molecules are required to regenerate RuBP from five G3P molecules?
What two molecules are produced by the light reactions and used to power the Calvin cycle?
ATP and NADPH
What provides the carbon atoms that are incorporated into sugar molecules in the Calvin cycle?
Carbon dioxide (CO2)
The light reactions take place in the _________ and the Calvin cycle takes place in the _________.
The term "cycle" is used to describe the Calvin cycle because:
the process begins and ends with RuBP.
Which of the following occurs during the Calvin cycle of photosynthesis?
Carbon dioxide is converted to chemicals that can be used to make sugars.
If photosynthesis and respiration are almost symmetrical processes, how is energy lost in the process of converting sugar back into ATP?
Energy is lost as heat during glycolysis and respiration.
A line of mutated yeast cells, called Wee mutants, has no mitochondria. Their name comes from the fact that these cells are very small compared to other yeast cells. Which energy-harvesting processes can Wee mutants perform?
glycolysis and fermentation
At the end of glycolysis, the original carbons of the glucose molecule form:
two molecules of pyruvate.
If glucose is metabolized under completely anaerobic conditions, then pyruvate:
is converted by fermentation to CO2 and ethanol or to lactate.
All of the following are true statements about ATP EXCEPT that it is:
synthesized only within mitochondria.
If no oxygen is available to a cell, then the net ATP production resulting from the metabolism of a single glucose molecule is:
two ATP molecules.
Which event occurs in the fluid portion of the cytoplasm of a cell undergoing glucose metabolism?
How many of the carbons originally present in glucose continue to other reactions after glycolysis?
Six carbons are left in pyruvate molecules.
Select the correct sequence of steps as energy is extracted from glucose during cellular respiration.
glycolysis → acetyl CoA → citric acid cycle → electron transport chain
What is the correct general equation for cellular respiration?
C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + ATP energy
In what organelle would you find acetyl CoA formation, the citric acid cycle, and the electron transport chain?
Which statement describes glycolysis?
This process splits glucose in half and produces 2 ATPs for each glucose.
Which statement describes the citric acid cycle?
This process produces some ATP and carbon dioxide in the mitochondrion.
Which statement describes the electron transport chain?
This process uses energy captured from electrons flowing to oxygen to produce most of the ATPs in cellular respiration.
Where is the majority of the usable energy found at the completion of glycolysis, acetyl CoA formation, and the Krebs cycle?
What is the purpose of the electron transport chain?
To use energy from the passing of electrons in electron carriers into a high concentration of hydrogen ions
Where are the low-energy electrons located after the electron transport chain is completed?
They are located in the bonds of H2O.