Chapter 7

Question 1

What is photosynthesis?

Answer 1

The process where plants use light energy to make food molecules from carbon dioxide and water.

Question 2

What are the root words for photosynthesis?

Answer 2

Photo - light; synthesis - to put together.

Question 3

What is the summarized chemical equation for photosynthesis?

Answer 3

6 CO2 + 6 H2O → C6H12O6 + 6 O2

Question 4

What is the full equation for photosynthesis?

Answer 4

6 CO2 + 12 H2O → C6H12O6 + 6 O2 + 6 H2O

Question 5

What does autotroph mean?

Answer 5

Comes from Greek meaning ‘self-eater’: organisms that make their own food without consuming other organic molecules.

Question 6

What are photosynthetic producers?

Answer 6

Plants that produce the earth’s food supply and carry out photosynthesis.

Question 7

What is chlorophyll?

Answer 7

The green color in plants comes from chlorophyll pigment.

Question 8

Where does photosynthesis occur?

Answer 8

In the chloroplasts of plant cells.

Question 9

What are thylakoids?

Answer 9

Disk-like membranous structures in the stroma that contain chlorophyll.

Question 10

What is a granum?

Answer 10

A stack of thylakoids.

Question 11

Which molecules are oxidized and reduced in photosynthesis?

Answer 11

CO2 is reduced as it transforms into glucose; H2O is oxidized into O2.

Question 12

What are the two stages of photosynthesis?

Answer 12

Light reactions and the Calvin Cycle.

Question 13

Where do light reactions occur?

Answer 13

In the grana of the chloroplasts.

Question 14

What happens during light reactions?

Answer 14

Light is used to phosphorylate ADP into ATP and reduce NADP+ to NADPH.

Question 15

Where does the Calvin Cycle occur?

Answer 15

In the stroma, the open fluid-filled part of the chloroplast.

Question 16

Where are most chloroplasts found in a plant?

Answer 16

In the mesophyll of the leaves.

Question 17

What part of the electromagnetic spectrum powers photosynthesis?

Answer 17

Photosynthesis is powered by a small part of the visible light spectrum.

Question 18

What are stomata?

Answer 18

Small pores on the undersurface of the leaf through which CO2 enters and O2 exits.

Question 19

What light does chlorophyll-a absorb?

Answer 19

Mainly blue-violet and red light.

Question 20

Why do leaves appear green?

Answer 20

Chlorophyll-a reflects and transmits green light, allowing our eyes to perceive the leaves’ typical color.

Question 21

What is chlorophyll-b?

Answer 21

A pigment that absorbs blue and orange light and has a yellow appearance. It assists Chlorophyll a in providing energy for the pigment.

Question 22

What is the stroma?

Answer 22

The thick fluid in the chloroplasts.

Question 23

What are carotenoids?

Answer 23

Pigments that help dissipate excess light energy that could damage chlorophyll; they are orange in appearance.

Question 24

Photosystem

Answer 24

Groups of clustered chlorophyll pigments that make energy collecting units

Question 25

How the photo systems were names?

Answer 25

Named in the order they were discovered, photosystem I and photosystem II

Question 26

Photon

Answer 26

A packet of light energy often referred to as a particle of light

Question 27

Reaction center

Answer 27

A single chlorophyll molecule that donates excited electrons to a primary electron acceptor

Question 28

Primary electron accepter

Answer 28

The molecule that makes ATP and NADPH molecules for use in the Calvin cycle

Question 29

P680, Photosystem II

Answer 29

Best absorbs the red-orange light that had a wavelength of p680 nm

Question 30

P700,Photosystem I

Answer 30

Best absorbs the red light that has a wavelength of 700nm

Question 31

1st step in the light reactions

Answer 31

Photons hit photosystem II

Question 32

2nd step of the light reactions

Answer 32

The molecules of antennae assist the p680 reaction center to split a water molecule obtaining 2 H+ and freeing 2 electron to send to the primary electron acceptor

Question 33

3rd step of the light reactions

Answer 33

The 2 electrons start an electron transport chain in the thylakoid membrane which pumps more H+ ions across the thylakoid membrane. ATP is produced by chemiosmosis with help of ATP sentence.

Question 34

4th step in the light reactions

Answer 34

The electrons are then sent to photosystem I in the molecules of antenna assist the P 700 Reaction Center to send the electrons on a smaller electron transport chain were NADP+ is reduced to NADPH

Question 35

5th step of the light reactions

Answer 35

The ATP and the NADPH are then sent to the Calvin cycle to manufacture sugars

Question 36

Three products of the light reactions

Answer 36

ATP, NADPH, and O2

Question 37

Photophosphorolation

Answer 37

The production of ATP by light

Question 38

Where the CO2 that is used in the Calvin cycle comes from

Answer 38

Enters the typical plant by diffusion through the leaf’s stomata on the leaf’s undersurface

Question 39

What defines a C-3 plant

Answer 39

C3 means that the plants utilizes CO2 directly from the air to make a 3 carbon compound 3-PGA

Question 40

General description of a c-4 plant

Answer 40

Made for dry condition. When their stomata close they can continue with regular photosynthesis

Question 41

How C-4 plants perform differently than C-3 plants

Answer 41

C4 plants have a special enzyme that allows them to make CO2 from a 4- carbon compound that is stored in plants tissues when the plant has its stomata open during times of adequate water.

Question 42

Examples of c-4 plants

Answer 42

Corn, sugar cane , sorghum

Question 43

How CAM plants different from C-4 plants (nighttime)

Answer 43

During the night when temperatures are lower and humidity is higher, the plants open their stomata and allow the entry of CO2 and the exit of O2. The next day the plant closes the stomata to prevent water loss and the banked carbon is split back into CO2 to conduct photosynthesis.

Question 44

Examples of CAM plants

Answer 44

Cactus, jade plants, pineapples, and other succulent plants