BIOC 212 Lecture Notes - Lecture 53: Gibbs Free Energy, Electrochemical Gradient, Mitochondrial Matrix

1. (1 point) What are transferred in an oxidation-reduction reaction? *

• atoms

• electrons

• ions

• protons

2. (1 point) In the reaction of beryllium with fluorine, which atom is oxidized? *

• fluorine

• beryllium

• neither of them

• both of them

3. (1 point) Ag - - > Ag ^+ +1 e^- This equation represents the type of reaction called _____. *

• hydrolysis

• oxidation

• redox

• reduction

4. (1 point) What is the reducing agent in the following reaction? 2K + S - - > K2S *

• K

• S

• K2S

• None of the above

5. (1 point) The oxidation number of oxygen when it is in a compound other than a peroxide is ____. *

• -2

• -1

• 0

• +2

6. (1 point) What is the oxidation number for each atom in NH4F? *

• N=+3, H=-4, F=+1

• N=-3, H=+1, F=-1

• N=+3, H+1, F=-1

• N=-3, H=-1, F=+1

7. (1 point) Which atom has a change in oxidation number of +4 in the following redox reaction?K2Cr2O7 + H2O + S - - > KOH + Cr2O3 + SO2 *

• K

• Cr

• O

• S

Metal activity series for question 8

8. (1 point) Of the following metals, which ions are most easily reduced? Use the above table to answer the question. *

• magnesium

• lead

• copper

• sodium

9. (1 point) In a zinc-copper cell, Zn(s) | Zn^+2(1M) || Cu^+2(1M) | Cu(s), which electrode is positive? *

• Cu^+2

• Cu(s)

• Zn(s)

• Zn^+2

10. (1 point) How must a redox reaction that is to be used as a source of electrical energy be set up? *

• One half reaction must involve two metals.

• Two half reactions must use a metal wire electrodes.

• One half reactions must involve more than one electron.

• Two half reactions must be physically separated.

11. (1 point) In a voltaic cell at which electrode does reduction occur? *

• anode only

• cathode only

• both anode and cathode

• Either anode or cathode , depending on the metal

12. (1 point) What assures that there is no charge build up in a voltaic cell as oxidation and reduction occur? *

• one of the half cells

• the electrolyte solutions

• the moving electrons

• the salt bridge

13. (1 point) In the most common dry cell what material is the electrode that is the center rod made of? *

• copper

• graphite

• lead

• zinc

14. (1 point) To charge a lead storage battery you must ________. *

• apply a direct current to it.

• hold a magnet close to it.

• Use alternating current through it.

• increase the oxygen in it.

15. (1 point) In a hydrogen- oxygen fuel cell ______________. *

• hydrogen diffuses through the cathode.

• hydrogen and oxygen are mixed before entering the anode.

• oxygen diffuses through the anode.

• oxygen diffuses through the cathode.

16. (1 point) When electrical energy is used to cause a chemical reaction we call this process _____. *

• electronation

• electrolysis

• hydration

• reduction

17. (1 point) Which of the following is true about an electrolytic cell? *

• It changes chemical energy into electrical energy.

• It is the type of cell used in electrocution

• It uses an electric current to make a nonspontaneous reaction go.

• All of the above

18. (1 point) The products formed in the net reaction of the electrolysis of water are ____. *

• aqueous hydrogen ion and hydroxyl ion

• hydrogen gas and oxygen gas

• hydrogen gas and liquid oxygen

• water vapor

19. (1 point) What occurs in electroplating? *

• decomposition of an ionic compound

• decomposition of a salt layer

• deposition of a metal layer on a material

• deposition of a salt layer on a metal

Open response Questions : Answer questions 20 through 22 in complete sentences

20. ( 5 points) Write the equation for the reaction of calcium and oxygen ( 1 point). Write the oxidation numbers for both the reactants and the products ( 2 points) What is the reducing agent and why? ( 2 points)

21. ( 5 points) Tell how a voltaic cell works. Be sure to mention the various parts of the voltaic cell and what they have to do with how it works.

22. (4 points) What are the signs given to the electrodes in both the voltaic and electrolytic cells? What reaction (oxidation or reduction) is occurring at each?

1.When something appears blue, it is absorbing all colors except__________.

yellow

blue

red

green

orange

2.During heavy exercise, lactic acid can build up in ourmuscles. Why? How does this resemble the metabolism of bacteria andyeast?

lactic acid is results from insufficient oxygen during sugarmetabolism; it is fermentation

lactic acid accumulates when we are dehydrated; bacteria andyeast use the same pathway

lactic acid is built up from carbon dioxide; bacteria and yeaststore energy in this way

3.Why must a cell keep a similar concentration of dissolvedsubstances with the fluid surrounding them?

to avoid dilution of potential energy

to avoid osmotic imbalance and rapid gain or loss of water

to maintain the correct amount of dehydration and hydrolysis

4.What is entropy?

the amount of energy in a system

the amount of disorganization

the amount of organization

5.Burning a log is the reverse reaction found in photosynthesis.What products would be formed in burning a log?

carbon dioxide and water

glucose and oxygen

oxygen and carbon dioxide

oxygen and water

6.The main reason that cellular respiration needs to occur stepby step instead of a single, big reaction is

cells don't store enough oxygen

too much energy would be released for the cell to harness

cells don't have many mitochondria.

cells produce the enzymes needed for cellular respiration veryslowly

7.Enzymes are catalysts because they operate to:

raise activation energy

lower activation energy

supply activation energy

supply the reactants

8.When ATP powers a reaction it becomes ADP. The ADP

can reform ATP by an exergonic reaction

is a waste product for lysosomal breakdown

can reform ATP by an endergonic reaction

can reform ATP by an oxidation reaction

can reform ATP by an equilibrium reaction

9.The energy source that drives photosynthesis is

water

glucose

carbon dioxide

oxygen

sunlight

10. What is the process by which enzymes regulate their ownactivity?

osmosis

self-propulsion

feedback inhibition

11.Coupled reactions are reactions in which a

endergonic reaction drives a spontaneous reaction

exergonic reaction drives a spontaneous reaction

endergonic reaction drives an exergonic reaction

exergonic reaction drives an endergonic reaction

12.How is water used in photosynthesis?

as a substrate for ATP synthase

as an electron donor

to combine with ADP forming ATP

as an electron acceptor

13.Why are the “Dark Reactions” of photosynthesis referred to as“Dark”?

they do not require light

they can only occur at night

they generate excess sugar and the leaves turn brown

14.What is the difference between potential and kineticenergy?

potential is stored, kinetic is being used

potential is being used, kinetic is ready to be used

potential is negative, kinetic is positive

15.The products of cellular respiration are

carbon dioxide, water, and ATP

glucose, water, and ATP

glucose, carbon dioxide, and ATP

oxygen, ATP, and water

carbon dioxide, glucose, and water

16.All of the following are correct about energy except:

The biological world gets its energy from the sun.

Chemical bonds store potential energy.

A boulder perched on a hill has kinetic energy.

Energy is defined as the ability to do work.

All forms of energy can be converted to heat.

17.What is needed for the end product of glycolysis, pyruvate,to enter the citric acid cycle?

More glucose for energy

ATP

Oxygen

Carbon dioxide

18.The enzyme that forms a transmembrane channel in mitochondriaand phosphorylates ADP

a carrier protein

ATP synthase

acetyl CoA

19.Fermentation is most common in

plants

microorganisms

animals

20.During adsorption of sunlight by photosystems, H+ ions aregenerated. Where do they come from? What are they used for?

from the breakdown of sugar; they help form water

water; they help form sugar

from carbon dioxide; they help dissolve NaCl

21.Glycolysis

does not use oxygen

uses oxygen

uses carbon dioxide

22.Photosynthesis is

not dependent on chlorophyll

a process that produces glucose and oxygen

a process that produces water and carbon dioxide

23.Breakdown of glucose generates many ATP molecules, each ofwhich can be used independently. Why is ATP ideally suited to powerbiological reactions?

ATP has many hydrogen bonds

ATP has enough energy to power one biological reaction

ATP readily dissolves in water

24.Objects that are not actively moving but have the capacity todo so are said to possess:

kinetic energy

entropy

potential energy

living energy

25.The first stage of cellular respiration, called ___________,takes place in the cytoplasm of the cell and needs no oxygen.

photorespiration

citric acid cycle

glycolysis

oxidation

26.Diffusion

requires energy

utilizes proteins to move molecules across a membrane

moves molecules against a concentration gradient

does not require energy

cannot occur without a membrane present

27.What is the name of the molecule on which an enzymeworks?

substrate

monomer

polymer

28.ATP contains

phenylalanine

two phosphate groups

three nitrate groups

three phosphate groups

29.How does chlorophyll function in photosynthesis?

by absorbing carbon dioxide

by absorbing the sun's energy

by absorbing water

30.Objects that are moving are said to possess:

living energy

potential energy

entropy

kinetic energy

31.The respiration pathway that evolved first is probably

glycolysis

aerobic respiration

citric acid cycle

32.The energy source for the process of photosynthesis is

oxygen

sunlight

carbon dioxide

chlorophyll

glucose

33.Burning wood generates heat and light. What type of reactionis this?

exergonic

kinetic energy

endergonic

potential energy

equilibrium

34.What is meant by a “coupled reaction” in terms of energy?

many poymers are built simultaneously

energy released by one reactions powers another reaction

some reactions occur in the same organelle

35.The First Law of Thermodynamics states:

energy is constantly being created by entropy events

energy can be changed from one form to another, but cannot becreated or destroyed

energy can be used and then destroyed because of entropy'sactions on it

energy can be destroyed while it is producing entropy

36.How do we dispose of the carbon derived from the glucose thatis metabolized during respiration?

by breathing out

via our urine

it is broken down in lysosomes

37.Both plant and animal cells have mitochondria because theyboth

carry on respiration

carry on photosynthesis.

require water

38.What is Activation Energy?

the energy needed to initiate a reaction

the energy that transports water into cells

potential energy

39.If you put a plant in a chamber and shine a light on it

oxygen will decrease and carbon dioxide will increase

oxygen will increase and carbon dioxide will decrease

oxygen and carbon dioxide will increase

oxygen and carbon dioxide will decrease

40.What are the inputs and the output molecules for the overallphotosynthetic process?

input sugar and oxygen; output carbon dioxide and water

input oxygen and water; output sugar and carbon dioxide

input carbon dioxide and water;output sugar and oxygen

41.What kind of reaction is photosynthesis?

endergonic

kinetic energy

exergonic

potential energy

equilibrium

42.In the process of glycolysis, glucose is cleaved into a pairof three-carbon molecules called

lactate

pyruvate

acetyl CoA

ATP

alcohol

43.Entropy is

order

disorder

complexity

Both order and disorder are correct

Both complexity and disorder are correct

44.Glycolysis takes place in the _____________ and the citricacid cycle and electron transport chain take place in the___________.

cytoplasm; endoplasmic reticulum

mitochondria, chloroplast

mitochondria; cytoplasm

cytoplasm; mitochondria

45.The organelle that carries out photosynthesis in plants isthe

mitochondria

chloroplast

ribosome

chlorophylllysosome

46.The energy to power the Calvin cycle comes from

cellular respiration

oxygen

the light reactions of photosynthesis

47.Which of the following can be broken down into intermediateproducts that enter cellular respiration?

Proteins

Lipids

Carbohydrates

All of these.

48.When cellular product levels get too high, the responsibleenzyme is inhibited. This is an example of

promotion

denaturation

equilibrium

a coenzyme

feedback inhibition

49.How is respiration the opposite of photosynthesis?

respiration breaks sugar down to carbon dioxide; photosynthesisbuilds sugar from carbon dioxide

respiration builds sugar from carbon dioxide; photosynthesisbreaks sugar down to carbon dioxide

respiration requires energy input; photosynthesis gives offexcess energy

50.The molecule that absorbs sunlight for photosynthesis is

oxygen

carbon dioxide

chlorophyll

glucose

sunlight