Lab 10: Photosynthesis

Question 1

The ability to convert solar energy into chemical energy is a trait of what?

Answer 1

autotrophs

Question 2

What is a by-product of photosynthesis?

Answer 2

oxygen

Question 3

What is the molecular formula of photosythesis?

Answer 3

6 CO2 + 12 H2O uses light energy to convert to C6H12O6 + 6 H2O and 6 + O2

Question 4

What are the reactants of photosynthesis?

Answer 4

Water and Carbon Dioxide

Question 5

What are the products of photosynthesis?

Answer 5

Glucose
Water
Oxygen Gas

Question 6

Where does photosynthesis occur?

Answer 6

The chloroplasts

Question 7

Where are pigments located?

Answer 7

in the thylakoid phospholipid bilayer

Question 8

What are the four types of pigments used in this lab?

Answer 8

Chlorophyll A
Chlorophyll B
Carotene
Xanthophylls

Question 9

Heavy pigments go farther. T or F?

Answer 9

F

Question 10

What is the equation for Rf?

Answer 10

distance moved by the pigment/ distance moved by the solvent front

Question 11

List the pigment in order of increasing molecular weight?

Answer 11

Beta Carotene, Xanthophyll, Chlorophyll A, Chlorophyll B

Question 12

What pigment will likely move the farthest?

Answer 12

Beta Carotene

Question 13

What pigment has the greatest Rf value?

Answer 13

Beta Carotene

Question 14

Small Rf indicated small molecular weight? T or F

Answer 14

F

Question 15

What could prevent the movement on the solvent if you were to touch the chromatography paper?

Answer 15

lipids

Question 16

What is DPIP

Answer 16

blue dye indicator

Question 17

What is DPIP functioning as in this experiment?

Answer 17

electron acceptor

Question 18

What type of electron acceptor does DPIP mimic?

Answer 18

a final electron acceptor in the light dependent reaction

Question 19

What is the electron acceptor that DPIP replaces?

Answer 19

NADP+

Question 20

What color is DPIP in its oxidized form?

Answer 20

blue

Question 21

What color is DPIP in its reduced form?

Answer 21

colorless

Question 22

When loosing electrons a molecule is being (reduced/oxidized)?

Answer 22

oxidized

Question 23

When gaining electrons a molecule is being (reduced/oxidized)?

Answer 23

reduced

Question 24

When DPIP accepts electrons it is becoming (reduced/oxidized)?

Answer 24

reduced

Question 25

In what way does DPIP signify that photosynthesis is occurring?

Answer 25

Color change

Question 26

What is added to the spinach smoothie solution to keep it isotonic?

Answer 26

sucrose solution (0.5 M)

Question 27

What are the two versions of the spinach solution being observed?

Answer 27

boiled and unboiled

Question 28

What parts of the spinach are affected by boiling?

Answer 28

The proteins and the pigments in the thylakoid membrane

Question 29

What was the wavelength used in this experiment and what color does this signify?

Answer 29

635 nm (red)

Question 30

What was being "absorbed" in this experiment?

Answer 30

635 nm (red) light

Question 31

Why did absorbance decrease over time?

Answer 31

The electrons are being used for photosynthesis

Question 32

What color experienced transmittance the most through this experiment?

Answer 32

Blue

Question 33

What color did the solution turn as photosynthesis occurred (unboiled reaction)?

Answer 33

from blue to green

Question 34

What color did the solution turn for the boiled spinach?

Answer 34

from blue to blue (no color change)

Question 35

Why did the color of the unboiled solution fail to change?

Answer 35

wasn't reduced (DPIP didn't change)

Question 36

Was the rate of photosynthesis positive or negative for the unboiled spinach? Why?

Answer 36

Negative because electrons were used, therefore there were less and less available to reduce DPIP

Question 37

What was the expected rate of the boiled spinach?

Answer 37

zero

Question 38

What is the opposite of transmittance?

Answer 38

absorbance

Question 39

The light that makes it through the liquid chamber is (more/less intense)?

Answer 39

less intense

Question 40

What is a colorimeter measuring?

Answer 40

The amount of light transmitted through a sample

Question 41

The color of the solution is the color of the light that passes through. T or F?

Answer 41

T

Question 42

Would electrons be transferred to DPIP in the dark? Why?

Answer 42

No, light energy required to carry out light reactions and DPIP is the final electron acceptor in light reactions