CHAPTER 5-ENERGY

Question 1

Photosynthesis; SLIDE 14

Answer 1

Plants capture energy from the sun and store it in chemical bonds of sugars and other food molecules

Question 2

Cellular Respiration

Answer 2

Organisms release energy stored in the chemical bonds of food molecules they eat (or the sugar they produce in photosynthesis and) use it as fuel

Question 3

Kinetic Energy

Answer 3

energy of motion, such as legs pushing pedals, birds flapping wings and the rapidly moving molecules in a fire

Question 4

Potential Energy

Answer 4

energy stored in an object, such as water trapped behind a dam, or a skier poised at the top of a hill;

Question 5

Chemical Energy

Answer 5

is a form of potential energy stored in chemical bonds

Question 6

First Law of Thermodynamics

Answer 6

states that energy is always conserved, it cannot be created or destroyed; In essence, energy can be converted from one form into another

Question 7

Second Law of Thermodynamics

Answer 7

is about the quality of energy; It states that as energy is transferred or transformed, more and more of it is wasted ; the Second Law also states that there is a natural tendency of any isolated system to degenerate into a more disordered state.

Question 8

Entropy

Answer 8

a thermodynamic quantity representing the unavailability of a system’s thermal energy for conversion into mechanical work, often interpreted as the degree of disorder or randomness in the system.

Question 9

ATP

Answer 9

adenosine triphosphate: adenine, ribose (sugar), phosphate groups (high energy bonds)

Question 10

ADP

Answer 10

adenosine diphosphate: adenine, ribose (sugar), phosphate groups

Question 11

High Energy Bonds

Answer 11

takes energy to make bonds & energy is released when broken; LOOK AT POWERPOINT SLIDE 11

Question 12

Thylakoid

Answer 12

location of “photo synthesis reactions, where light energy is converted into chemical energy

Question 13

Stroma

Answer 13

location of “synthesis” reactions, where chemical energy from the “photo” reactions is used to synthesize sugar

Question 14

Photosynthesis Pigments

Answer 14

plants produce several different light- absorbing pigments; each photosynthetic pigment absorbs and reflects specific wavelengths

Question 15

Energy Movement through Chlorophyll; SLIDE 20-21

Answer 15

(1) light energy bumps an electron in the chlorophyll molecule to a higher, excited energy level (2) the excited electron generally has one of two fates: (a) some energy is transferred to a nearby molecule, where it excites another electron or (b) the excited electron is transferred to a nearby molecule

Question 16

The Water-Splitting Photosystem; SLIDE 24

Answer 16

(1) the energy from the excited electrons is transferred to nearby pigment molecules (2) at the reaction center, the primary electron acceptor grabs excited electrons and sends them to the electron transport chain (3) to replace electrons, water molecules are split, and oxygen and hydrogen ions are released as by-prodcucts

Question 17

The Photosynthetic Electron Transport Chain ; SLIDE 25-26

Answer 17

(1) Electrons move through the electron transport chain, releasing energy as they fall to lower energy state (2) the released energy powers proton pumps that move hydrogen ions from the stroma into the thylakoid (3) Protons rush out of the thylakoid - through the molecule ATP synthase-with great kinetic energy that is used to build ATP

Question 18

The Calvin Cycle ; SLIDE 28

Answer 18

(1) Fixation: the enzyme rubisco plucks carbon atoms, one at a time, from CO2 molecules in the air, attaching them to an organic molecule (2) Sugar Creation: the organic molecule is modified into a small sugar called G3P, using energy from ATP and NADPH; some molecules of G3P are combined to form six-carbon sugars such as glucose and fructose (3) Regeneration: some molecules of G3) are used to regenerate the original organic molecules, using energy from ATP (could take multiple cycles to produce a sugar)

Question 19

Glycolysis; SLIDE 37

Answer 19

occurs in cytoplasm; glucose is split into pyruvate; energy spent: 2 ATP ; energy acquired: 4 ATP, 2 NADH

Question 20

Acetly-CoA Production

Answer 20

(1) as each pyruvate is broken down, a pair of electrons ( and a proton) are passed to NAD+, producing NADH (2) a carbon and two oxygen are released as carbon dioxide (3) Coenzyme A attaches itself to the remaining molecule, creating acetyle CoA

Question 21

The Citric Acid Cycle ; SLIDE 39

Answer 21

(1) A NEW MOLECULE IS FORMED: an Acetly Co-A molecule enters the cycle and binds to oxaloacetate, creating a six carbon molecule (2) HIGH ENERGY ELECTRON CARRIERS (NADH) ARE MADE AND CARBON DIOXIDE IS EXHALED: the six carbon molecule donates electrons to NAD+, creating NADH; two carbon dioxide molecules are released into the atmosphere (3) OXALOACETATE IS REFORMED, ATP IS GENERATED, AND MORE HIGH ENERGY ELECTRON CARRIERS ARE FORMED: the remaining four carbon molecule is rearranged to form oaxalocacetate, in the process, ATP is formed and the electrons are passed to form NADH and FADH2

Question 22

The Mitochondrial Electron Transport Chain ;SLIDE 41

Answer 22

High energy electrons are passed from the carriers NADH/ FADH2 to a series of molecules embedded in the inner mitochondrial membrane called the electron transport chain; Steps on PP slide

Question 23

Respiration

Answer 23

Glucose+O2—> CO2+ H2O+ ATP; exchange of gases, breathing: obtain oxygen, release carbon dioxide, cellular respiration: harvesting energy from food molecules by cells

Question 24

Cellular Respiration (oxygen present)

Answer 24

electron receptor: oxygen–> end product: water

Question 25

Fermentation

Answer 25

IN ANIMALS: electron receptor: Pyruvate–> end product: lactic acid; IN YEAST: electron receptor: Acetaldehyde –> end product: Ethanol