Question

7.         The reaction in which inorganic phosphate, Pi, is released from ATP is an example of?

a.         respiration

b.         photosynthesis

c.         oxidation

d.         reduction

e.         none of the above

8.         The final electron acceptor for electrons passed through the electron transport chain of aerobic respiration is

a.         oxygen

b.         lactate

c.         NAD+

d.         electron transfer proteins

e.         pyruvate

9.         The “polar nature” of water means that:

            a.      sea level tends to be higher at the north and south poles.

       b.    as global warming occurs, the ice floating at the north pole will melt and cause

              sea level to rise.

            c.      one end of a water molecule is partly positive and the other end is partially     negative.

            d.      as global warming occurs, the ice on top of Antarctica will melt and cause sea

              level to rise.

            e.      both b and d.

10.       Which photosynthetic pigment(s) looses (loose) an electron directly in the light reaction?

a.         NADPH

b.         carotenoids

c.         chlorophyll a

d.         b and c

e.         none of the above

11.       Enzymes:

a.      allow nonspontaneous reactions to occur spontaneously

b.      must be resynthesized after every reaction

c.      can catalyze an upper limit of around 1000 reactions per hour

d.      reduce the energy of activation required for a spontaneous reaction to occur

e.      function most efficiently at low temperatures.

12.       O₂ that is produced during photosynthesis is derived from:

a.      H₂O

b.      CO₂

c.         C₆H₁₂O₆

d.         H₂S

e.      ATP

13. Sulfur contains 16 protons. How many electrons will it have in its second energy shell?

a.         2

b.         6

c          8

d          10

e          16

14.       How many electrons must be added to make sulfur maximally stable?

a.         2

b.         6

c          8

d          10

e          16

15.       The end product of glycolysis is:

a.         acetyl CoA

b.         lactate

c.         Citric acid

d.         pyruvate

e.         ethanol.

16.       Denaturation of an enzyme (a protein) by heating does which of the following?

a.         renders it ineffective by changing its natural shape

b.         enhances its performance

c.         reduces its energy of motion

d.         nothing, all remains the same

17.       When carbon atoms are lost from molecules during respiration, they are given off in the form of:

a.         methane gas

b.         carbon dioxide

c.         carbon atoms

d.         pyruvic acid

e.         molecular oxygen

18.       In order for life to exist on earth, even today, entropy (the tendency for molecules to become disordered) must be overcome. The ultimate source of energy to keep the molecules of living things ordered, and therefore alive, comes from:

a.         fossil fuels

b.         heat in the earth's core

c.         wind energy

d.         heterotrophic organisms

e.         the sun

19.       6CO₂ + 6H₂0 -> C₆H₁₂O₆ + 6O₂ is the general equation for:

        a.      photosynthesis

b.         respiration

20.       ATP is used to:

a.         code messenger RNA

b.         couple exergonic to endergonic reactions

c.         transport phosphorus in the cell

d.         lower activation energy

e.         raise activation energies

21.       In the visible spectrum, the light of highest energy is:

a.         the light with the shortest wavelengths

b.         red light

c.         fluorescent light

d.         both a and b

22.       The most common molecules in cells are:

a.         Carbohydrates

b.         Water

c.         Proteins

d.         Lipids

e.         Salts

23.       The most important result of the light-independent (or Calvin Cycle) reactions is:

a.         the addition of phosphate to sugar to form sugar phosphate

b.         the synthesis of sugar from CO₂

c.         the change of chlorophyll from green to colorless

d.         the transfer of electrons to glucose molecules

e.         the rearrangement of sugar molecules to form O₂ from H₂O

24.       The breakdown of large molecules by the enzymatic addition of water is an example of a(n) _____ reaction

a.         oxidation

b.         reduction

c.         dehydration

d.         hydrolysis

e.      synthesis

25.       Which has more energy:

a.         table sugar (sucrose) with 12 carbons

b.         olive oil with about 55 carbons

26.       A reaction from a higher free-energy molecule to a lower free-energy molecule is:

            a.      exergonic

            b.      endergonic

            c.      unlikely to occur spontaneously

            d.      dependent on combustion to start the reaction.

27.       Carbohydrate produced by photosynthesis in a plant cell can:

            a.      be used for respiration in the mitochondrion of the same plant cell.

            b.      be transported to another plant cell and used there for respiration.

            c.      taken up by a cow chewing on the leaf and used for its respiration.

            d.      taken up by a grub chewing on the plant root and used for its respiration.

            e.      all of the above.

28.       Plants are green because

a.         chlorophyll absorbs green light

b.         chlorophyll does not absorb green light

c.         chlorophyll reflects red and blue light

d.         carotenoids absorb green light

e          green light has the lowest energy

29.       The art of making bread and wine is thousands of years old. What energy-releasing pathway is responsible for both these legacies of human culture.

a.         aerobic respiration

b.         alcoholic fermentation

c.         lactate fermentation

d.         glycolysis

e.         none of the above

30.       The emperor penguins of Antarctica live on a diet of fish and crustaceans obtained from the cold Antarctic seawaters. During their annual breeding cycle, however, they migrate across the frozen continent to their breeding grounds 50 miles away from the sea (and their source of food). For more than 2 months, the male penguins care for and incubate the eggs while the females return to the sea to feed. During this time the males can lose up to 50% of their biomass (by dry weight). Where did this biomass go?

a. The mass was released as CO2 and H2O

b. The mass was converted to energy and used up.

c. The mass was converted into ATP molecules

d. The mass was broken down to amino acids and eliminated from the body.

e. The mass was converted to urine and feces and eliminated from the body.

31.       A potted geranium plant is kept watered in a dark closet. After a week it will weigh:

            a.         less because it is still respiring.

            b.         less because no photosynthesis is occurring.

            c.         more because the light independent (dark reactions) Calvin cycle continues.

            d.         the same because no biomass is produced.

            e.         more because it still has access to water and nutrients in the soil.

32.       Where do the light-dependent reactions of photosynthesis take place?

a.         grana

b.         stroma

c.         outer membrane

d.         cristae

e.         a and b

34.       Where are the enzymes of the Krebs Cycle located?

a.         cytoplasm

b.         outer mitochondrial membrane

c.         mitochondrial matrix

d.         inner mitochondrial membrane

e.         inter-membrane space of mitochondrion

35.       Why must one refer to a "net gain" of 2 ATP's per molecule of glucose undergoing glycolysis when 4 ATP's are actually produced?

a.         in order to account for the 2 ATP's used as activation energy

b.         because ATP's produced by substrate-level phosphorylation are less energized than those produced by oxidative phosphorylation

c.         in order to account for the 2 NAD⁺s used

d.         in order to account for the 2 inorganic phosphates added in the middle steps of the process

36.       Enzymes are used up in chemical reactions.

            a.         True

            b.         False

41        Hydrogen bonds in water are due to an attraction between

a.         a hydrogen on one water molecule and a hydrogen on a neighboring water molecule

b.         a hydrogen on one water molecule and an oxygen on a neighboring water molecule

c.         an oxygen on one water molecule and an oxygen on a neighboring water molecule

d.         all of the above

42        Electron transfer proteins are found mainly in

            a.         mitochondria and chloroplasts

            b.         nuclei

            c.         cilia and flagella

            d.         all of the above

43        Make this a true statement: _____ undergo photosynthesis, ____ undergo respiration.

            a. plants; animals

            b. plants; plants

            c. plants; plants and animals

            d. plants and animals; plants and animals

            e. all of the above

44        What ratio of C:H:O defines a carbohydrate?

a.         1:3:1

b.         1:2:1

c.         2:1:2

d.         2:2:2

Essay

1 (6 pts). What is the first law of thermodynamics and explain how it relates to the function of ecosystems on earth.

(6 pts). Describe three major differences between plant and animal cells.

Answer 1

8)a) Oxygen

It is necessary for aerobic respiration,it becomes water upon being reduced by the accepted electron, without the presence of oxygen electron would remain bound in the final step of ETC(electron transport chain) , preventing further reaction.

12)a)water

Oxygen during photosynthesis come from spit water molecule

During photosynthesis plant absorbs water and carbon dioxide after absorption water convert into oxygen and hydrogen and later joined to the Corbin dioxide to create a sugars and it is light dependent reaction

14)a)2

According to octet rule most atoms gain stability in their outer most level by filling the S and P orbitals of highest energy level with eight electron

Sulfur electronic configuration is 1s² 2s²2p⁶3s²3p⁴

additional 2 electron fill to the p orbital give the stability to sulfur 1s²2s²2p⁶3s²3p⁶

15)d) pyruvate

Glycolysis involves the breaking down of a sugar in to more manageable compounds in order to produce energy,end product is 2 pyruvate molecule

19)a) photosynthesis

I'm supposed to answer only 4 question as our guidelines .

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