POB Chapter 6

ATP contains

an adenine base, a ribose sugar, and three phosphate groups

Which of the following statements is not true concerning enzymatic activity? 1. As the temperature increases, most enzymatic reactions will still proceed at the same rate 2. Enzyme activity increases as substrate concentration increases until the maximum rate is acheived 3. Above a certain temperature, an enzyme will become denatured 4. Each enzyme has a preferred pH at which the enzyme reaction rate is highest.

As the temperature increases, most enzymatic reactions will still proceed at the same rate

Which of the following statements most accurately describes the first law of thermodynamics? 1. One usable form of energy cannot be completely converted into another usable form 2. One usable form of energy can be completely converted into another usable form 3. Energy cannot be created or destroyed. 4. Energy can be neither created nor destroyed but it can be changed from one form to another

Energy can be neither created nor destroyed but it can be changed from one form to another

Which of the following statements is true about enzymes? 1. They are unaffected by changes in pH 2. They catalyze only one specific type of reaction 3. Their 3D shape can vary and still be active 4. They can associate with a wide variety of substrates 5. Boiling temperature do not affect their activity

They catalyze only one specific type of reaction

If A -> B-> C -> D -> E represents a metabolic pathway, then letter E would be

a product

The location in which the enzyme and substrate complexes is called the

active site

if an enzymatic reaction was controlled by feedback inhibition, we would expect it to stop

as soon as a critical level of end product builds up

Which of the following is not a correct statement about the second law of thermodynamics and entropy 1. living cells without energy become less organized 2. carbon dioxide and water form glucose without the input of energy 3. to maintain organization of a cell, a continual input of energy is required 4. the amount of disorder in the universe is always increasing

carbon dioxide and water form glucose without the input of energy

The main reason that ATP is considered the energy currency in cells is because it

contains accessible energy in phosphate bonds

If you wished to increase enzyme activity, you would do all of the following except 1. decrease the temperature 2. change to optimum pH for the reaction 3. increase the concentration of substrate 4. increase the temperature moderately

decrease the temperature

C6H12O6 versus H20 and C02: molecule on the left

has more potential energy, has a less stable configuration, and is more organized

The function of an enzyme is to

increase the rate of a metabolic reaction

This image demonstrates the second law of thermodynamics in that (solar energy - chemical energy - mechanical energy; heat being given off)

the animal loses some energy to heat when chemical energy is converted to mechanical energy

During an enzymatic reaction, what happens to the enzyme?

the enzyme and the substrate form a temporary complex

This image demonstrates the first law of thermodynamics in that (solar energy - chemical energy - mechanical energy; heat being given off)

the plants convert light energy from the sun to chemical energy

In feedback inhibition of a metabolic pathway, where does the inhibitor bind?

to the enzyme of the first reaction