Biology 20: Module 5: Lesson 21Assignment

(30Marks) / Module 5: Lesson 2 ASSIGNMENT
This Module 5: Lesson 2 Assignment is worth 30 marks. The value of each assignment and each question is stated in the left margin.

Lesson 2Assignment: Light-Dependent Reactions

(16 marks) /

LAB

(8marks) / /

Using Chromatography to Separate Plant Pigments

Complete the following chart. You may have completed “Investigation 5.B” from pages 172 and 173 of the textbook in a laboratory setting. If so, you may complete the following chart using your own chromatography paper from the investigation. If you were unable to perform the investigation, use the diagram provided in this assignment to help you fill out the chart. Once you have filled out the chart, answer questions 1 to 4.

Diagram of a Leaf Pigment Chromatogram


Chromatography Analysis
Pigment Name / Pigment Colour / Distance Travelled by Pigment (cm) / Distance Travelled by Solvent Front (cm) / Reference Flow (Rf)
carotenes
chlorophyll A
chlorophyll B
xanthophylls
(1 mark) /
  1. The presence of pigments other than chlorophyll in plants is important because these pigments
  1. are used to build chlorophyll
  2. can use oxygen to carry out photosynthesis
  3. function in exactly the same way as chlorophyll
  4. allow the plant to utilize wavelengths of light other than those used by chlorophyll

Answer:

(4 marks) /
  1. Describe two practical uses for an artificial chemical that behaves like chlorophyll. Explain the value of each of the uses to society.

Answer:

(1 mark) /
  1. If a certain band on one chromatography strip has been identified as chlorophyll a, chlorophyll a could be identified on a second chromatography strip by looking for a band
  1. with no colour
  2. of darker colour
  3. in reverse position
  4. in a parallel position

Answer:

(2 marks) /
  1. Describe a practical application of chromatography, and give an example that is unrelated to photosynthesis.

Answer:

(14 marks) /

Reflect and Connect

(4 marks) /
  1. How can your new knowledge of photosynthesis help to solve world fuel shortages? Scientists have looked to hydrogen as an alternative clean-burning fuel. The catch is that hydrogen is not free in nature. The amount of energy required to split H2O is more than what is obtained when hydrogen is burned.Explain why scientists are investigating ways to produce hydrogen using an artificial system similar to photosystem II.

Answer:

(10 marks) /
  1. Summarize in point form, by illustration, by podcast, or by poem the events that take place in the light-dependent reactions of photosynthesis.

Answer:

Once you have completed all of the questions, submit your work to your teacher.