Procedure I – Net Photosynthesis Rates – 100% Illumination

Procedure I – Net Photosynthesis Rates – 100% Illumination

Complete the tables below using your data and information found under the Background tab (see the Summary of Needed Formulas section)

4

TableTop Science – All Rights Reserved

1

Leaf

Sample

Type

Illumination

Level

Oxygen

Concentration

Change Data (ppm)

Elapsed

Time

(s)

Oxygen

Change Rate

(ppm/s)

Sun-

Adapted

100% 21.36 40.0 (s)
Shade-Adapted 100% 12.96 40.0 (s)
Leaf

Sample

Type

Illumination

Level

Carbon Dioxide

Concentration

Change Data

(ppm)

Elapsed

Time

(s)

Carbon Dioxide

Change Rate

(ppm/s)

Sun-

Adapted

100% -21.36 40.0 (s)
Shade-Adapted 100% -12.96 40.0 (s)

Observations and Questions

[1] Show your oxygen change rate calculation for the Sun-Adapted data run.

[2] Show your carbon dioxide change rate calculation for the Shade-Adapted data run.

[3] Examine your results. Do your results reveal a possible relationship between (rates of) production of oxygen and carbon dioxide? Explain. Cite your results as part of your explanation.

[4] Using your results for change in oxygen concentration as a reference, discuss whether your Procedure I results confirm research findings about differences in the amount of chlorophyll production for sun-adapted and shade-adapted leaves.

[5] How is the net photosynthesis rate related to the rates you determined? (note that this is not a calculation)

[6] Explain why (or why not) you would expect respiration to occur when the illumination is 100%?

Procedure II – Respiration Rates – 0% Illumination Data Run

Complete the tables below using your data and information found under the Background tab (see the Summary of Needed Formulas section)

2

3

Leaf

Sample

Type

Illumination

Level

Oxygen

Concentration

Change Data (ppm)

Elapsed

Time

(s)

Oxygen

Change Rate

(ppm/s)

Sun-

Adapted

0% -14.01 40.0 (s)
Shade-Adapted 0% -8.41 40.0 (s)
Leaf

Sample

Type

Illumination

Level

Carbon Dioxide

Concentration

Change Data (ppm)

Elapsed

Time

(s)

Carbon Dioxide

Change Rate

(ppm/s)

Sun-

Adapted

0% 14.01 40.0 (s)
Shade-Adapted 0% 8.41 40.0 (s)

Observations and Questions

[7] Sample Calculation: Show your oxygen change rate calculation for the Sun-Adapted data run.

[8] Sample Calculation: Show your carbon dioxide change rate calculation for the Shade-Adapted data run.

[9] Cite your results for the change in carbon dioxide concentration as a reference and compare the respiratory rates for sun-adapted and shade-adapted leaves. Explain the biological principles/bases underlying this comparison.

[10] What would be the photosynthesis rate if you measured it at 0% illumination in Procedure II? Explain your answer. Cite your results from Procedure I to assist with your explanation.

Procedure III – Low-Light Net Photosynthesis Rates – 15% Illumination

Complete the table below using your data and information found under the Background tab (see the Summary of Needed Formulas section)

Leaf

Sample

Type

Illumination

Level

Oxygen

Concentration

Change Data (ppm)

Elapsed

Time

(s)

Oxygen

Change Rate

(ppm/s)

Sun-

Adapted

15% 4.78 40.0 (s)
Shade-Adapted 15% 8.19 40.0 (s)

4

TableTop Science – All Rights Reserved

5

Observations and Questions

[11] Sample Calculation: Show your oxygen change rate calculation for the Sun-Adapted data run.

[12] Based on the data you collected in Procedures I (100% illumination) and III (15% illumination), which system of leaves produces the most oxygen: Sun-adapted or shade-adapted? Explain how your results support your answer.

[13] Are your results from Procedure II and Procedure III consistent with research findings that there are differences in chlorophyll production and enzyme activity between shade-adapted leaves and sun-adapted leaves? Explain your reasoning. Cite your results from Procedure II and Procedure III to support your explanation.

"Get 15% discount on your first 3 orders with us"
Use the following coupon
FIRST15

Order Now