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Flashcards in Photosynthesis Deck (84)
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1
Q

make their own energy

A

autotrophs

2
Q

heterotrophs

A

get energy from other organisms

3
Q

Chloroplasts are found where?

A

mesophyll of leafs

4
Q

Define mesophyll

A

interior tissue of leafs

5
Q

Thylakoids are found where?

A

inside the chloroplast

6
Q

Thylakoids do what?

A

help capture sunlight for plants

7
Q

Thylakoids are arranged in stacks called _____.

A

grana

8
Q

Region of fluid filled space outside the thylakoids is the ______.

A

stroma

9
Q

Define pigment

A

substances that absorb visible light

10
Q

Chlorophyll transmitts _____ light, absorbs all others

A

green

11
Q

There are other pigments such as __________ _ and _________ present in plants.

A

Chlorophyll B; carotenoids

12
Q

Device that measures a pigment’s ability to absorb various wavelengths of light

A

Spectrophotometer

13
Q

How do spectrophotometers work?

A

sends light through pigments and measures amount of light transmitted

14
Q

a graph plotting a pigment’s light absorption versus wavelength

A

absorption spectrum

15
Q

The absorption spectrum of chlorophyll suggests that what type of light work best for photosynthesis?

A

violet-blue and red light

16
Q

tells you which wavelength of light actually drives photosynthesis the best

A

action spectrum

17
Q

Who made an action spectrum using algae and bacteria?

A

Engelmann

18
Q

What do chloroplasts do with light?

A

use light photons to help take electrons from water

19
Q

Where do the electrons taken from water go?

A

The electrons are then added to CO2 to make glucose

20
Q

Photosynthesis is a _____ process in which H2O is oxidized and CO2 is reduced

A

Redox

21
Q

To gain electrons

A

reduction

22
Q

to lose elctrons

A

oxidation

23
Q

Light reaction requires _______.

A

sunlight

24
Q

Light reaction happens where?

A

In thylakoid

25
Q

In light reaction, what happens to water?

A

Water is oxidized

26
Q

Light reaction produces ______ & ___.

A

NADPH; ATP

27
Q

The _________ ___________ contain photosystems.

A

thylakoid membranes

28
Q

Describe photosystem

A

pigment molecules attached to proteins that funnels light energy into a reaction center where electrons are transferred

29
Q

The proteins that photosystems are attached to are what?

A

light harvesting complex

30
Q

In photosystems, what happens with light? (Light Reaction)

A

Light comes in; electrons come out.

31
Q

First step in photosystem II (Light Reaction)

A

Light first enters photosystem II

32
Q

What happens when light enters photosystem II? (Light Reaction)

A

The light excites chlorophyll molecules, who excite other chlorophyll molecules by passing on photons.

33
Q

What happens meanwhile light is entering photosystem II? (Light Reaction)

A

Water is split into hydrogen and oxygen by enzymes

34
Q

What happens to the oxygen and hydrogen when the water is split? (Light Reaction)

A

The oxygen is released as waste. The hydrogen is kept.

35
Q

P680 is named so why?

A

it prefers 680nm light

36
Q

What is P680?

A

a special chlorophyll molecule in photosystem II that takes electrons from the hydrogen that came from the split water

37
Q

Where do the photons being passed by the chlorophyll go? (Light Reaction)

A

They get sent to P680

38
Q

What happens to P680 when it receives photons? (Light Reaction)

A

P680 gets so exited that it loses the electrons it received

from water.

39
Q

Describe Primary Electron Acceptor (Light Reaction)

A

a molecule in the reaction center that

receives electrons from P680.

40
Q

Describe linear flow (Light Reaction)

A

The primary electron acceptor sends the electrons down the electron transport chain (ETC) to Photosystem I

41
Q

During linear flow movement of the electrons is used for what? (Light Reaction)

A

to make ATP

42
Q

As electrons move, what happens? (ATP Production)

A

they cause the Hydrogens (protons) from water to move out of the membrane into the thylakoid space.

43
Q

As hydrogens build up in the thylakoid space, what happens? (ATP Production)

A

they are forced back through the membrane through ATP synthase into the stroma.

44
Q

enzyme that makes ATP as hydrogens pass through

A

ATP synthase

45
Q

Where does PI get its electrons? (Light Reaction)

A

from the ETC

46
Q

____ in photosystem I is going to receive electrons coming from the ETC (Light Reaction)

A

P700

47
Q

What does light do in PI? (Light Reaction)

A

Light excites chlorophyll molecules in PI who excite other chlorophyll molecules by passing on photons

48
Q

What happens when photons are sent to P700? (Light Reaction)

A

P700 who gets so excited that it loses the electrons it got from the ETC.

49
Q

Describe cyclic flow (Light Reaction)

A

The primary acceptor can then send the electrons back to the top of the ETC so they call come down again and make more ATP

50
Q

The _______ _______ _________ receives the electrons from P700 (Light Reaction)

A

primary electron acceptor

51
Q

The primary acceptor in PI can also send the electrons to an electron carrier called _____ (Light Reaction)

A

NADP+

52
Q

How is NADPH created from NADP+? (Light Reaction)

A

Once NADP+ gets electrons to carry (gets reduced) it becomes NADPH

53
Q

The NADPH will take electrons to the stroma to do what? (Light Reaction)

A

begin the second cycle

54
Q

___ will also go to the stroma to help start the second cycle. (Light Reaction)

A

ATP

55
Q

The synthesis part is photosynthesis is called?

A

Calvin cycle

56
Q

What is another name for the Calvin cycle?

A

Light-Independent reaction

57
Q

Where does the Calvin cycle take place?

A

In stroma

58
Q

Calvin cycle does what with CO2?

A

reduces CO2

59
Q

Calvin cycle needs what two key molecules made in Light Reaction?

A

NADPH; ATP

60
Q

Calvin cycle produces what?

A

glucose

61
Q

What is the process called of incorporating Carbon dioxide (Calvin cycle Phase 1)?

A

carbon fixation

62
Q

The 5 carbon sugar in Phase 1-Step 1 of Calvin cycle is called what

A

RuBP

63
Q

Calvin cycle Phase 1-Step 1

A

An enzyme adds one CO2 to RuBP to make a 6 carbon sugar. (this happens three times)

64
Q

enzyme adds one CO2 to RuBP to make a 6 carbon sugar is called

A

rubisco

65
Q

Calvin cycle Phase 1-Step 2

A

The 6 carbon sugar then splits into two 3 carbon molecules

66
Q

What is Phase 2 of Calvin cycle

A

Reduction

67
Q

Calvin cycle Phase 2-Step 1

A

ATP is used to add a phosphate to the 3 carbon molecules (makes the molecule unstable)

68
Q

Calvin cycle Phase 2-Step 2

A

NADPH then reduces the 3 carbon molecule, replacing the newly added phosphate with electrons

69
Q

3 carbon molecule is now called ___. (Calvin Cycle Phase 2-Step 2)

A

G3P

70
Q

What is Phase 3 of Calvin Cycle?

A

Regeneration

71
Q

What is the point of regeneration of Phase 3?

A

replacing RuBP

72
Q

Calvin Cycle Phase 3-Step 1

A

1 Molecule of G3P is sent out to make glucose

73
Q

_ G3P’s make _ glucose

A

2 G3P’s make 1 glucose

74
Q

Calvin Cycle Phase 3-Step 2

A

5 Molecules of G3P are used to make 3 RuBP. This starts over the Calvin Cycle

75
Q

Describe C3 Plants

A

initial fixation of CO2, via rubisco, forms a three-carbon compound

76
Q

Most plants are what type?

A

C3

77
Q

What do C3 plants do on hot, dry days

A

plants close stomata, which conserves H2O but also limits intake of CO2

78
Q

What do C4 plants do on hot, dry days

A

counteract hot dry days by fixing CO2 into four-carbon compounds in mesophyll cells.

79
Q

C4 requires the enzyme ___ _________ because it can fix CO2 even when there isn’t much of it.

A

It requires the enzyme PEP carboxylase because it can fix CO2 even when there isn’t much of it.

80
Q

C4-The four-carbon compounds are send to ______-______ ____, where they release CO2 that is then used in the Calvin cycle

A

bundle-sheath cells

81
Q

Goal of C4 plants

A

Increases CO2 for the calvin cycle when stomata are closed to save water

82
Q

CAM plants do what?

A

Cam plants use CAM to fix CO2 into 4 carbon molecules

83
Q

CAM plants open their stomata when?

A

at night

84
Q

Main process of CAM plants

A

Stomata close during the day, and CO2 is released from the 4 carbon molecules and used in the Calvin cycle