Spinach Leaf Chromatography Lab Report

Chromatography Lab

Riley Borklund
Table 5, Seat 2A
Lab Partners: Martin, Katherine, and Dakari
Honors Biology, Mrs. Semaan
January 5, 2016 Abstract: The purpose of this lab is to find what pigments are in a spinach leaf. The only pigments visible to the eye are chlorophyll a and chlorophyll b. We know this because chlorophyll reflects the green wavelength of light and shows us that it is present. We also, however, wanted to know what else is present in the spinach leaf. The way we found this is by using chromatography paper. After following the procedure, the chromatography paper revealed that Carotene, Xanthophyll, Chlorophyll a, and chlorophyll b are present in a spinach leaf.

Introduction: This lab is an investigation

The constants include the spinach leaf, quarter, jar, solvent, chromatography paper, and ruler.

Materials: spinach leaf, quarter, jar with lid, solvent, chromatography paper, ruler

Procedure:
Obtain a jar containing 1 cm of chromatography solvent. This jar is closed because the solvent is volatile, and you should be careful to keep the lid on as much as possible.
Obtain an 8cm square piece of chromatography paper and one fresh spinach leaf.
Make two pencil marks 1.5 cm from one edge of the chromatography paper.
Lay the leaf on the chromatography paper near one edge. Using the marks as a guide, lay a ruler on top of the leaf, so that the edge of the ruler is on the paper 1.5 cm from and parallel to the edge.
Using the ruler as a guide, roll a coin over the leaf so that you drive the leaf pigments into the paper in a straight line, 1.5 cm from the edge of the paper. You should see a dark green stripe of pigment. If not, repeat this step using the same 1.5-cm line, but reposition the leaf so that you are rolling the coin over fresh leaf tissue. Use a pencil to mark the location of the bottom of the pigment line on the paper. Use this line as the

Analysis: The chromatography paper revealed that chlorophyll a, chlorophyll b, carotenes, and xanthophylls, are present in a spinach leaf. This is because a plant needs several different types of pigments in order to photosynthesize properly while simultaneously protecting itself from the dangers of too much sunlight. Chlorophyll a is the primary photosynthetic pigment in all plants, however, all of the other pigments are important as well because they are the ones that provide extra layers of protection in order to shield the plant from harm.

Discussion/conclusions: I accept my hypothesis because the data from the lab revealed that a spinach leaf does not only have chlorophyll, although that is all we can see with our naked eye, but also contains carotenes and xanthophylls that help to protect it. One thing I learned through this lab is that chlorophyll, although it is very important to the plant, it is not the only pigment that is important. The other pigments are also very important because the plant needs protection. Plants do not have mobility and cannot control how much sunlight they get, so they need all the protection they can get- especially if they are in a place where they are exposed to sunlight for excessively long periods of