Photosynthesis

Question 1

What does ATP stand for?

Answer 1

Adenine triphosphate

Question 2

What parts make up ATP?

Answer 2

One molecule of adenine, one molecule of ribose, and three phosphate groups

Question 3

What does ADP stand for?

Answer 3

Adenine diphosphate

Question 4

What parts make up ADP?

Answer 4

One molecule of adenine, one molecule of ribose, and two phosphate groups

Question 5

Why and how does ADP turn into ATP?

Answer 5

When a cell has excess energy available, it adds a third phosphate group to the ADP, storing a small amount of energy in the bonds between the phosphate groups and producing ATP

Question 6

What is the main job of ATP?

Answer 6

Be the basic energy source of the cell by storing and releasing energy when needed

Question 7

How does ATP release energy to be used by the cell?

Answer 7

It breaks off its third phosphate group, breaking the bond that was storing the energy so the energy can be released and used

Question 8

What is the main job of ADP?

Answer 8

Provide a space where a cell can store excess energy

Question 9

What analogy is used to picture ATP and ADP?

Answer 9

ADP is like a partially charged battery that can be fully charged up by adding an additional phosphate group. ATP is like a fully charged battery that can by used by breaking off a phosphate group

Question 10

What is the first law of thermodynamics?

Answer 10

Nothing (no form of energy) can be created or destroyed (it can only change forms)

Question 11

What do electron receptors do? Give an example of an electron receptor

Answer 11

Accept electrons that need to be transferred
NADP+

Question 12

How is NADP+ turned into NADPH? Vice versa?

Answer 12

Sunlight is absorbed by chlorophyll, energizing electrons. Two electrons and one hydrogen ion are attached to the NADP+, turning it into NADPH
When energy needs to be used, the two electrons are released from the NADPH, breaking off the hydrogen ion as well, producing NADP+

Question 13

What are electron carriers (How do they work)?

Answer 13

Compounds that can accept a pair of high-energy electrons and transfer them, along with most of their energy, to another molecule

Question 14

What is an example of an electron carrier? What can it do?

Answer 14

NADPH
Carry the high-energy electrons produced by light absorption in chlorophyll to chemical reactions elsewhere in the cell

Question 15

What is chlorophyll?

Answer 15

The principle pigment found in plants

Question 16

What is the chlorophyll’s job in photosynthesis?

Answer 16

Capture energy from sunlight

Question 17

Why are plants green?

Answer 17

Chlorophyll absorbs all energy from light wavelengths in the form of colors except for green, which it reflects, making plants appear green

Question 18

Why do leaves change colors in the fall?

Answer 18

The chlorophyll found in the leaves begins to die as the temperature drops, so less green is reflected and the other colors being absorbed can be seen

Question 19

What is the chloroplast?

Answer 19

The organelle found in plant cells where photosynthesis takes place

Question 20

What are the parts of the chloroplast?

Answer 20

Thylakoids and the stroma

Question 20

What are thylakoids? What structures do they form?

Answer 20

Sacklike membranes containing chlorophyll and other pigments arranged in stacks called grana

Question 21

What is the stroma?

Answer 21

The jelly-like substance that fills the spaces between grana within the chloroplast

Question 22

What are the reactants and products of photosynthesis?

Answer 22

Reactants - Carbon dioxide + Water
Products - Sugars + Oxygen

Question 23

What is the balanced equation of photosynthesis?

Answer 23

6CO2 + 6H2O —light–> C6H12O6 + 6O2

Question 24

What are the two reactions that occur during photosynthesis?

Answer 24

Light-dependent reaction and light-independent reaction (Calvin cycle)

Question 25

What are the products of the light-dependent reactions? How are they used?

Answer 25

ATP and NADPH, which are used up in the Calvin cycle and return to the light-dependent reactions as ADP and NADP+ to be recharged and used again

Question 26

Where in the chloroplast do the light-dependent reactions of photosynthesis occur?

Answer 26

The thylakoid

Question 27

Where in the chloroplast do the light-independent reactions of photosynthesis occur?

Answer 27

The stroma

Question 28

How do the light-dependent and light-independent reactions of photosynthesis relate and work together?

Answer 28

The ATP and NADPH created during the light-dependent reactions are used in the light-independent reactions to produce sugars

Question 29

Where is the electron transport chain located?

Answer 29

Within the membrane of the thylakoid

Question 30

What is the overall goal of the electron transport chain?

Answer 30

Convert ADP and NADP+ into the energy carriers ATP and NADPH

Question 31

What are the parts of the electron transport chain?

Answer 31

Photosystem II, electron transport proteins, photosystem I, second chain of electron transport proteins, and ATP synthase

Question 32

What are the abbreviations for each part of the electron transport chain?

Answer 32

Photosystem II = PSII Photosystem I = PSI Electron transport protein chains = ETCs

Question 33

What are the 6 steps of the electron transport chain?

Answer 33

1. Sunlight charges the electrons found in PSII, and the electrons continue down the chain 2. The PSII splits water molecules into hydrogen ions (which remain in the thylakoid) and oxygen (which is released from the plant), and the electrons released by the split enter the PSII and replace the sunlight-charged electrons 3. Electrons move through the ETC, and energy from the electrons is used to pump hydrogen from the stroma across the membrane and into the thylakoid 4. Electrons enter the PSI and are recharged by sunlight 5. Electrons enter the second ETC, and their energy is used to transform NADP+ into NADPH, which is sent to the stroma 6. Hydrogen atoms from the thylakoid move through the ATP synthase, causing the synthase to spin, which creates energy to transform ADP into ATP

Question 34

What is ATP synthesis?

Answer 34

The process in which hydrogen ions are moved across the thylakoid membrane and ATP is formed

Question 35

What is the energy source used in the light-dependent reactions of photosynthesis?

Answer 35

Sunlight

Question 36

What is the energy source used in the light-independent reactions of photosynthesis?

Answer 36

The ATP and NADPH produced in the light-dependent reactions

Question 37

What is the stomata?

Answer 37

Tiny openings on a plant's leaves that open to allow carbon dioxide to enter the plant and oxygen to exit

Question 38

What are the 4 steps of the Calvin cycle?

Answer 38

1. Carbon dioxide enters the stroma 2. ATP and NADPH energy is used to create sugar from the carbon, releasing ADP and NADP+ 3. Sugar (glucose) is released to be used by the pant 4. ATP is used to turn the remaining molecules into the starting molecule, restarting the process

Question 39

What factors affect photosynthesis?

Answer 39

Temperature, light intensity, and availability of water

Question 40

Why and how does temperature affect photosynthesis?

Answer 40

Photosynthesis relies on enzymes that function best between 0 and 35 degrees Celsius. Temperatures above or below this may damage the enzymes, slowing or completely stopping the process

Question 41

How does light intensity affect photosynthesis?

Answer 41

Increasing the amount of light a plant receives will increase the rate of photosynthesis until you reach a certain point of light intensity, at which the speed of photosynthesis reaches its max and cannot increase any further

Question 42

How are some plants adapted to live in extremely hot environments?

Answer 42

Their somata only open at night when it is cooler so they do not lose as much water to evaporation

Question 43

What is an autotroph?

Answer 43

An organism that makes its own food

Question 44

What is a heterotroph?

Answer 44

An organism that obtains its food by consuming other living things