Chapter 10

Question 1

Photosynthesis

Answer 1

• the process that converts solar energy into chemical energy
• helps nourish the biosphere

Question 2

Chloroplasts

Answer 2

found in plants

- use photosynthesis to capture light energy from the sun and convert it into stored sugars and organic molecules

Question 3

Autotrophs

Answer 3

• are major producers of the biosphere that produce organic molecules from CO2
  i. e. plants

Question 4

2 types of Autotrophs

Answer 4

1) Photoautotrophs

2) Chemoautotrophs

Question 5

Photoautotrophs

Answer 5

use the energy of sunlight to make organic molecules from water and CO2

i.e. plants

Question 6

Chemoautotrophs

Answer 6

.

Question 7

Heterotrophs

Answer 7

• live on organic compounds produced by other organism
• are the consumers of the biosphere
• i.e. animals, fungi, and many prokaryotes

Question 8

Where photosynthesis occurs?

Answer 8

• plants
• algae
• certain other protists
• some prokaryotes

Question 9

Chloroplasts

Answer 9

• the sites of photosynthesis in plants
• found in the mesophyll cells forming the tissues in the interior of the leaf
• the organelles in which photosynthesis occurs

Question 10

Leaves of plants

Answer 10

major sites of photosynthesis

Question 11

Chlorophyll

Answer 11

leaf color comes from this

Question 12

Stomata

Answer 12

the pores in the leaf through which O2 and CO2 leave and enter

Question 13

The composition of Chloroplasts

Answer 13

• 2 membranes around an aqueous space
• the stroma
• contain thylakoids and grana

Question 14

Thylakoids

Answer 14

stacked into grana

contain the chlorophyll

Question 15

Photosynthesis overview

Answer 15

6 CO2 + 12 H2O + Light source => Glucose + 6 O2 + 6 H2O

Question 16

overall chemical reaction change during photosynthesis is the …

Answer 16

• reverse of cellular respiration

- anabolic

Question 17

Anabolic

Answer 17

energy (sugar synthesizing) reaction

Question 18

Chloroplasts split …

Answer 18

H2O => H2 + O2

- incorporating the electrons of H2 into sugar molecules

Question 19

Photosynthesis is a redox reaction

Answer 19

H2O is oxidized

CO2 is reduced

Question 20

2 stages of photosynthesis

Answer 20

1) The light (photo) reactions

2) The Calvin Cycle (synthesis)

Question 21

1) The light (photo) reactions

Answer 21

• occurs in the grana,
• split H2O, release O2,
• produce ATP, and form NADPH

Question 22

2) The Calvin Cycle (synthesis)

Answer 22

• occurs in the stroma
• Input: ATP, NADPH, CO2
• Output: Sugar, ADP + P + NADP+

(forms sugar from CO2, using ATP for energy and NADPH for reducing power)

Question 23

Light Reaction convert…

Answer 23

solar energy to the chemical energy of ATP and NADPH

Question 24

Light

Answer 24

• is a form of electromagnetic energy: which travels in waves

Question 25

Wavelength

Answer 25

the distance between the crests of waves and determines the TYPE of electromagnetic energy

Question 26

Visible Light Spectrum

Answer 26

includes colors of light we can see and the wavelengths that drives photosynthesis

Question 27

Pigments

Answer 27

i. e. Chlorophyll a

- substances that absorb visible light and reflect the light that we see

Question 28

Action-Spectrum

of a pigment profiles

Answer 28

the relative effectiveness of different wavelengths of radiation in driving photosynthesis

• 1st determined by Theodor W. Engelmann 1833

Question 29

Chlorophyll a

Answer 29

the main photosynthetic pigment

Question 30

Chlorophyll b

Answer 30

an accessory pigment

Question 31

Accessory pigments

Answer 31

absorb different wavelengths of light and pass the energy to chlorophyll a

Question 32

when a pigment absorbs light

Answer 32

its electrons become unstable and goes from a ground state to an excited state, that releases heat energy and sometimes fluorescence

Question 33

in the Thylakoid Membrane

Answer 33

chlorophyll is organized with other proteins into a photosystem

-ATP is produced in here

Question 34

Photosystem

Answer 34

composed of a reaction center (chlorophyll a) surrounded by a number of light-harvesting complexes or pigment molecules

Question 35

Light-harvesting complexes

Answer 35

funnel the energy of photons of light to the reaction center

Question 36

Reaction-Center chlorophyll molecules

Answer 36

absorbs energy and as the electrons “fall” to a lower energy level, their energy is harnessed to produce ATP

Question 37

Chemiosmosis in Chloroplasts vs. Mitochondria

Answer 37

Both organelles:
- redox reactions of electron transport chains generate a H+ gradient across a membrane

• use ATP synthase and proton-motive force to make ATP

Question 38

Calvin Cycle

Answer 38

uses ATP and NADPH to convert CO2 => sugar

occurs in the stroma
has three phases
(carbon fixation, reduction, regeneration of CO2 acceptor)

similar to the Citric Acid Cycle

Question 39

3 phases of the Calvin Cycle

Answer 39

1) Carbon fixation
2) Reduction
3) Regeneration of the CO2 acceptor