Excerpts from Photosynthesis Abstract Sections

Good Excerpts

Note that while none of these quotes would stand alone as a good Abstract, a number of these ideas combined together might do quite nicely.

• Chlorophyll A, chlorophyll B, xanthophylls, and carotenes were extracted from a spinach leaf using paper chromatography. Once the pigments had been absorbed into the paper, they were identified, cut apart from each other, and redissolved in 100% ethanol.
• Carotene was determined to be the smallest molecule because it moved the farthest, with the xanthophylls, chlorophyll A, and chlorophyll B following, respectively.
• Using a spectrophotometer, an absorption spectrum was obtained for each pigment. Readings were obtained at 25 nm increments from 350 to 800 nm.
• The carotenes, xanthophylls, and chlorophyll B all reached maximums at 450 nm, while the chlorophyll A reached its maximum at 425 nm. Minimums were 625, 575 to 650, 525 to 600, and 525 nm, respectively.
• The various food colorings tested were yellow, red, blue, and green. Maximum absorptions were determined to be 400 to 425, 525, 625, and 625 nm, resptectively. Minimums were 550 to 650, 600, 475, and 525 to 700 nm, respectively.
• Elodea was inserted into test tubes containing bicarbonate solution. Some of the test tubes also contained various food colorings. Some were placed in the light, while others were placed in the dark. The change in fluid volume in each tube was calculated to determine the amount of oxygen evolved.

Not So Good Excerpts (including some grammatical problems)

• In the first part of the photosynthesis lab distinguishing between the different pigments on the spinach leaf was the first thing that was needed to be done. The colors that were abstracted from the piece of leaf on the chromatography paper was a pea green, a bluish green, yellow, and lastly there was a orange color.
• A spinach line was created on a piece of paper chromatography submitted into 90% pet ether and 10% acetone to test which pigment was the first to appear.
• 90% petroleum ether and 10% acetone were placed in the bottom of a flask. Fumes accumulated, while chromatography paper was cut. Spinach line was made, chromatography paper placed in flask with a t-pin. Pigments were cut apart and placed in respective test tubes.
• A 250 mL Erlenmeyer flask was filled with 90% petroleum ether and 10% acetone solution. Spinach was rolled onto a piece of chromatography paper. The paper was attached to a stopper with a T-pin and then the tip was placed into the flask. The pigments were separated and placed into separate test tubes along with 5 mL of 100% EtOH and sealed with Parafilm.
• Next, for each of these different pigments we determined the absorption spectra and found the maximum absorbance and also where the minimum absorbance was at. The carotenes was at 450nm minimum absorbance was at 550nm to 600nm. . .
• The results showed that all items tested had a common wavelength between each. The relative wavelength that the absorbance was at a constant was received at 500-650 nm. The blue and green food coloring did not have a common absorbance. The highest absorbance for the pigments and the food coloring was received at 6 absorbance by red food coloring. . .
• Elodea was found to give off more oxygen when submitted into red food coloring at a rate of 237.50%. The Elodea was tested by submitted into different food coloring and one with out food coloring. The yellow was the next food coloring to have a high rate of oxygen evolution was the yellow food coloring at 162.50%. . .

(I’m not entirely sure what some of these mean. I just copied them “as-is.” —jsc)