Chapter 5: Energy and Life

Enzymes increase the rate of reaction by ) contributing electrons to the reaction ) contributing water to the reaction ) decreasing activation energy ) changing the pH of substrates ) increasing the temperature of substrates

Decreasing activation energy

Usually, enzymes are ) monosaccharides ) phospholipids ) steroids ) fats ) proteins

Proteins

An enzymes function is dependent on its ) size ) shape ) weight ) temperature ) pH

Shape

Which of the following is true for all exergonic reactions? ) the reaction proceeds with a net release of free energy ) the products have more total energy than the reactants ) some reactants will be converted to products ) a net input of energy is required for the reaction to proceed ) the reactions are non spontaneous

The reaction proceeds with a net release of free energy

Some bacteria are metabolically active in hot springs because ) high temperatures make catalysis unnecessary ) their enzymes are completely insensitive to temperature ) that are able to maintain a cooler internal temperature Their enzymes have high optimal temperatures

Their enzymes have high optimal temperatures

The region of an enzyme where the substrate binds is called the _____ site ) active ) conformational ) enzymatic ) substrate ) denatured

Active

How can one increase the rate of a chemical reaction

Add a catalyst

Sucrose is a disaccharide, composed of monosaccharides glucose and fructose. The hydrolysis of sucrose by the enzyme sucrose results in )bringing glucose and fructose together to form sucrose ) breaking the bond between glucose and fructose and forming new bonds from atoms of water ) the release of water from sucrose as the bond between glucose and fructose is broken

Breaking the bond between glucose and fructose and forming new bonds from atoms of water

How does a noncompetitive inhibitor decrease the rate of an enzyme reaction? )By decreasing the activation energy of a reaction ) by changing the free energy change of the reaction ) by changing the shape of the reactant ) by acting as a coenzyme for the reaction

By acting as a coenzyme for the reaction

Which term most precisely describes the cellular process of breaking down large molecules into smaller ones? ) Metabolism ) catabolism ) catalysis ) dehydration ) anabolism

Catabolism

If you have a severe fever, what may be the grave consequence?

Change in the folding of enzymes

A chemical reaction with a positive change in energy (delta G) is correctly described as ) endergonic ) spontaneous ) exothermic ) endothermic ) enthalpic

Endergonic

Which of the following statements is the first law of thermodynamics ? ) kinetic energy is stored energy that results from the specific arrangement of matter ) energy cannot be created or destroyed ) energy cannot be transferred or transformed ) the entropy of the universe is decreasing ) the entropy of the universe is comstant

Energy cannot be created or destroyed

What term is used to describe the transfer of free energy from catabolic pathways to anabolic pathways? ) bioenergetics ) entropy ) feedback regulation ) energy coupling

Energy coupling

The energy required to initiate an exergonic reaction is called

Energy of activation

Which of the following is a measure of disorder? ) conservation of energy ) respiration ) potential energy ) entropy ) kinetic energy

Entropy

Substances that plug up an enzymes active site are ) enzyme products ) enzyme substrates ) enzyme inhibitors ) ractants

Enzyme inhibitors

Which of the following statements regarding enzymes is true ) enzymes change the direction of chemical reactions ) enzymes decrease the free energy change of a reaction ) enzymes prevent changes in substrate concentrations ) enzymes increase the rate of reaction

Enzymes increase the rate of reaction

Catabolism is to anabolism as _____ is to _____ ) exergonic, spontaneous ) work, energy ) exergonic, endergonic

Exergonic, endergonic

Which of the following is most similar to that of an enzyme inhibitor ) changing tires on a car ) driving the wrong way on a one way street ) combining new ingredients in a new recipe ) keeping someone from parking by parking in their designated spot

Keeping someone from parking by parking in their designated spot

Which component in the following reaction is an enzyme? Lactose+lactase+water--> lactase+glucose+fructose

Lactase

Which component of the following reaction is the substrate? Lactose+lactase+water--> lactase+glucose+fructose ) fructose ) glucose ) lactose ) lactase

Lactose