Exam 3: How Cells Take in and Use Energy

A hummingbird is "drinking" nectar containing sugar from a red columbine flower. Arrange the following events to occur in the hummingbird in order from the first to last: (1)Glucose sugar is converted to pyruvate. (2)Energy from high-energy electrons is released from an electron transport chain. This energy is used to make ATP. (3)The hummingbird exhales carbon dioxide and energy is stored in electron carriers. (4)The hummingbird has the ability to beat its wings 40 - 80 times a second.

In photosynthesis, the light-dependent reactions

Which color of light has the least important role in photosynthesis?

Regulation of metabolism uses feedback inhibition. Describe how this type of mechanism regulates the production of ATP.

Why do you have to use an oven to transform batter into a cake?

How does an enzyme lower the energy of activation needed for a chemical reaction?

Almost all enzymes are

The role of oxygen in cellular respiration is to

Which of the following chemical reactions will provide most of the energy to the hummingbird so it can beat its wings 40 - 80 times a second?

What process occurs in both the aerobic and anaerobic pathways?

People adopt a vegetarian diet for a variety of reasons. Justify such a diet using the laws of energy and the idea of efficient energy usage.

Recall that your text states the following energy analogies: a.ATP is compared to a few coins in your pocket. b.Creatine phosphate is compared to a handful of dollars. c.The glycolytic system is like an account in the bank. d.The oxidative energy system is compared to stocks and bonds. In your own words explain why each is a valid comparison.

You have to light a fuse before a firecracker will explode. Would you classify this as an energy- releasing or an energy- absorbing reaction? Please explain your answer.

Burning fossil fuels releases carbon dioxide into the atmosphere. This additional carbon dioxide is causing a phenomenon called global warming. Which process "put" the carbon into our fossil fuels? Explain the process.

High temperatures can alter the three-dimensional shape of a protein. This process is called denaturing. How might this affect the activity of an enzyme?

The active site of an enzyme

The majority of ATP produced in cellular respiration is produced during

During the Calvin-Benson cycle (carbon-fixing reactions), in the red Columbine plant, high-energy electrons are transferred into a newly made 3-carbon compound. Eventually these electrons will end up as part of glucose molecules. What was the original source of these electrons in photosynthesis?

Hummingbirds break down glucose and other food molecules during cellular respiration. The carbon atoms in these organic molecules are released as ____________during the _____________.

All enzymes act by