Lab 4 Energy and BIO101
L
Photosynthesis
Student Name:
Access Code (located on the lid of your lab kit):
Lab Report Format Expectations
Utilize college level grammar and professional formaṄng when completing this worksheet.
Pre-Lab Questions
1. Chloroplasts and mitochondria are both unusual in that they have double membranes
and contain their own set of DNA. Can you think of any explanations for this observation?
These organelles likely originated from free-living bacteria that were engulfed by early
eukaryotic cells in an endosymbiotic event. Their double membranes and retained DNA
support this evolutionary theory.
2. Many deciduous trees have leaves that turn yellow in the fall. What do you suppose
is happening in the leaves at the cellular and molecular level?
As autumn approaches, chlorophyll breaks down and is reabsorbed, revealing the
underlying carotenoids that give leaves their yellow or orange color.
EXPERIMENT 1: PAPER CHROMATOGRAPHY
Introductory Questions:
1. What are you observing in this experiment?
I am observing how the pigments in a leaf extract separate on chromatography paper.
2. What factors affect the separation of the pigments in paper chromatography?
The separation is influenced by the polarity of the solvent, the solubility of each
pigment, and the interaction between the pigments and the paper.
3. What three solutions did you use in this experiment? Why did you use these three
different solutions?
I used acetic acid, acetone, and mineral oil. These solvents were chosen because they
have different polarities, which helps to separate pigments based on how each pigment
dissolves in a polar versus nonpolar medium. (If water was also used as a control,
mention that it provided a comparison to a highly polar environment.)
, Lab 4 Energy and BIO101
L
Photosynthesis
Data and Observations
Table 1: Part 1: Chromatography Data
Distance from
Solvent Original Line to Number of Bands Rf Factor
Solvent Font
Acetic Acid 8 1 0.17mm
Acetone 7.5 1 0.95mm
Mineral Oil 6.4 1 0.25mm
Water 6 4 0.67mm
Insert a picture of the four pieces of chromatography paper with your name and access code
handwritten in the background. (Part 1)
L
Photosynthesis
Student Name:
Access Code (located on the lid of your lab kit):
Lab Report Format Expectations
Utilize college level grammar and professional formaṄng when completing this worksheet.
Pre-Lab Questions
1. Chloroplasts and mitochondria are both unusual in that they have double membranes
and contain their own set of DNA. Can you think of any explanations for this observation?
These organelles likely originated from free-living bacteria that were engulfed by early
eukaryotic cells in an endosymbiotic event. Their double membranes and retained DNA
support this evolutionary theory.
2. Many deciduous trees have leaves that turn yellow in the fall. What do you suppose
is happening in the leaves at the cellular and molecular level?
As autumn approaches, chlorophyll breaks down and is reabsorbed, revealing the
underlying carotenoids that give leaves their yellow or orange color.
EXPERIMENT 1: PAPER CHROMATOGRAPHY
Introductory Questions:
1. What are you observing in this experiment?
I am observing how the pigments in a leaf extract separate on chromatography paper.
2. What factors affect the separation of the pigments in paper chromatography?
The separation is influenced by the polarity of the solvent, the solubility of each
pigment, and the interaction between the pigments and the paper.
3. What three solutions did you use in this experiment? Why did you use these three
different solutions?
I used acetic acid, acetone, and mineral oil. These solvents were chosen because they
have different polarities, which helps to separate pigments based on how each pigment
dissolves in a polar versus nonpolar medium. (If water was also used as a control,
mention that it provided a comparison to a highly polar environment.)
, Lab 4 Energy and BIO101
L
Photosynthesis
Data and Observations
Table 1: Part 1: Chromatography Data
Distance from
Solvent Original Line to Number of Bands Rf Factor
Solvent Font
Acetic Acid 8 1 0.17mm
Acetone 7.5 1 0.95mm
Mineral Oil 6.4 1 0.25mm
Water 6 4 0.67mm
Insert a picture of the four pieces of chromatography paper with your name and access code
handwritten in the background. (Part 1)
