Unit 4 Photosynthesis

Question 1

Define Photosynthesis

Answer 1

solar energy used to convert CO2 and H2O into sugar and O2

Question 2

Define Autotrophs

Answer 2

Organisms that make their own food
“self-feeders”

Question 3

Define Photoautotrophs

Answer 3

Autotrophs that use energy from light

Question 4

Define heterotrophs

Answer 4

the consumers of the Biosphere
-cannot make own food
-consume animals and plants

Question 5

Define Chlorophyl

Answer 5

Light absorbing pigment in the Chloroplasts

Question 6

how many chloroplasts does s mesophyll cell have

Answer 6

30-40 Chloroplasts

Question 7

Define Stomata

Answer 7

Pores that allow CO2 in the leaf and O2 out of the leaf

Question 8

Define veins

Answer 8

deliver water, minerals, sugars to all part of the plants

Question 9

Define a wavelength

Answer 9

the distance between the crests of the electromagnetic waves

Question 10

Define the Electromagnetic Spectrum

Answer 10

full range of wavelengths

Question 11

Define a Photon

Answer 11

Discreet packet of light energy

Question 12

Which wavelengths have more energy Longer or shorter

Answer 12

Shorter wavelengths have more energy

Question 13

Define Pigments

Answer 13

light absorbing molecules

Question 14

Where are pigments located?

Answer 14

build into the Thylakoid membranes

Question 15

How do Pigments work

Answer 15

absorb some wavelengths and reflect others

Question 16

Define Chlorophyll a

Answer 16

Absorbs blue-violet and red light

Question 17

What pigment participates directly in photosynthesis

Answer 17

pigment Chlorophyll a

Question 18

Define Chlorophyll b

Answer 18

Absorbs blue and orange light

Question 19

which pigment transfers energy to another pigment

Answer 19

Chlorophyll b

Question 20

Define Carotenoids

Answer 20

reflect shades of yellow and orange

Question 21

Define Photoprotection

Answer 21

protection from excessive light energy

some Carotenoids capture and dissipate excessive light energy

Question 22

What is the opposite of Cellular respiration

Answer 22

Photosynthesis

Question 23

What are the stages of Photosynthesis

Answer 23

1. Light reactions
2. Calvin cycle

Question 24

where do light reactions happen

Answer 24

In the Thylakoids

Question 25

where does the Calvin Cycle happen

Answer 25

in the Stoma -carbon fixation

Question 26

What is the first stage of Light reactions

Answer 26

1. Light energy is absorbed by chlorophyll 2. H2O is split and O2 is released 3. the electrons from H2O are transferred to NADP+ to reduce it to NADPH 4. ATP is produced

Question 27

how is solar energy gotten

Answer 27

a pigment molecule absorbs a photon which makes an electron jump to another energy level as the electron drops back down it releases energy in the form of heat or light

Question 28

Define Reaction Centre

Answer 28

pair of specialized chlorophyll a molecules bound to proteins

Question 29

which photosystem works first 1 or 2

Answer 29

Photosystem 2 works first

Question 30

Define Carbon Fixation

Answer 30

the incorporation of inorganic CO2 into Organic molecules which are reduced to form sugars

Question 31

what are the reactants of the Calvin Cycle

Answer 31

CO2 from air ATP and NADPH from light reactions

Question 32

What are the products of the Calvin Cycle

Answer 32

G3P

Question 33

How many main steps in the Calvin Cycle

Answer 33

4 main steps

Question 34

What is the first step of the Calvin Cycle

Answer 34

1. Carbon Fixation - starts with a 5-carbon sugar (RuBP) cycle turns 3 times to generate 1 molecules of G3P

Question 35

what is the second step of the Calvin cycle

Answer 35

2. Reduction - ATP and NADPH are used to reduce the 3-carbon Molecules to G3P

Question 36

what is the third step of the Calvin cycle

Answer 36

3. Release of G3P -every 3CO2 molecules, 1 molecule is released as a product

Question 37

what is the fourth step of the Calvin cycle

Answer 37

4. Regeneration of RuBP - 5 G3P molecules rearranged to make RuBP

Question 38

What are C3 Plants

Answer 38

start plants the use CO2 directly from the air due to hot/dry conditions the plants close their stomata to reduce loss of water when that id done the leaf also cannot get any CO2 in and O2 out

Question 39

what are C4 Plants

Answer 39

Fix carbon into a 4-carbon intermediate compound Storing the CO2 in one type of cell then releasing it into another cell to perform Photosynthesis

Question 40

What are CAM plants

Answer 40

adaptive to very dry climates -conserve water by only opening its Stomata at night then the CO2 is released during the day so the Calvin cycle can proceed