'Algal balls' - Photosynthesis using algae wrapped ..

Algal balls are a method of studying photosynthesis by using algae immobilised in an alginate gel

'Algal balls' - Photosynthesis using algae wrapped in jelly balls.

Some animals are capable of using photosynthesis for short periods of time in order to gain the essential proteins they need to survive. These animals, most living on the bottom of the ocean floor, ingest algae and keep the chloroplasts in their bodies for several months at a time. The chloroplasts allow for photosynthesis to take place so that these animals may live. Animals that are capable of doing this include corals, sponges, sea anenomies, and slugs. It has been discovered, in fact, that slugs possess some of the genes that plants have which allow the chloroplasts to get the proteins that they need. It is even believed that chloroplasts themselves may have started out as a form of symbiotic bacteria that adapted itself to the conditions inside plant cells. Chloroplasts maintain their own DNA separate from the plant's DNA and resembles the DNA of some forms of bacteria.

Measuring the rate of photosynthesis - Science and …

Photosynthesis can be treated with a top-down approach starting with gross primary productivity and relating the process to world food production and the base of food chains, or from a bottom-up perspective starting with the cell, chloroplast and biochemical detail. Experiments can come first to devise first principles about the factors necessary for and affecting the rate of photosynthesis, or can be used to reinforce theory. Experimental work can either use whole plants (e.g. Elodea in a photosynthometer) or plant parts (e.g. leaf discs) or cell free systems (e.g. Hill reaction) or manufactured units (e.g. immobilised algae balls).

» As time progressed, the cyanobacteria evolved into a chloroplast, and evidence proves such; ribosomes in chloroplast resemble that in cyanobacteria and much of the DNA are similar
[1] [2]
» By measuring the changes in O2 production, we can compare how the intensity and the light color affected photosynthetic rate
» In addition, we also performed a chromatography on the algae samples in order to determine the Rf values
» Using the Rf values we were then able to determine the pigments that were found in the algae
» For part 1 we observed green algae and cyanobacteria, and noticed a dispersion of iodine in the cyanobacteria, while we saw a concentration of iodine in the green algae

» This allowed us to conclude about the site of starch production/storage in each of these two organisms
Green Algae
Results II
» Chromatography: technique used to separate a mixture by passing the mixture through a medium whereby the components move at different rates
» The green pigment (spinach) had an overall Rf factor of 0.207, which corresponded with Chlorophyll c from the table
-The green-yellow pigment (algae sample) had an overall Rf factor of 0.728, which corresponded with Xanthophyll from the table
Results III Cont'd
» Results are not accurate because the green light should not have produced as much O2 as the others, and the white light should have produced more O2 than any of the three colored solutions especially when placed at a closer shorter distance due to the increased light intensity
» White light should have produced the most oxygen because more light should have been absorbed
» Green light should have had much less oxygen produced than any of the other solution because the majority of the light was absorbed by the green solution before it reached the plant (i.e photosynthesis would have been limited to the accessory pigments only and not the primary pigment)
Results III
» Results from the whole class averaged out focusing on the last column which is the volume of oxygen gas produced
» From this table we can see that the most oxygen was produced using white light at a distance of 5 cm and the least using white light at a distance of 30 cm
» Initially, if white light is used, photosynthesis is unaffected, but if the intensity changes, photosynthesis is affected
» As well, the color also affects photosynthesis.


Introduction to symbiotic algae which live in the tissues of animals such as sea slugs and corals. Students frequently wonder if photosynthesis would be a desirable attribute for animals or even humans. This page and related links explore photosynthesis using symbionts in animals.

How to Take Care of Marimo Balls

If 4 bottles that contain 21 algal balls are each placed in front of a light at different distances of 0 cm, 10 cm, 20 cm, and 30 cm, then the bottle at 0 cm will have the highest pH followed by 10 cm, 20 cm, and 30 cm, because the closer the bottle is to the light, the more light it is exposed to, thus causing a greater amount of photosynthesis.

Method sheets and a great slideshow with pictures of some stages

In this procedure, algae, immobilised in calcium alginate, provide a standardised amount of photosynthetic material, enabling semi-quantitative experiments to be undertaken. The rate of carbon dioxide uptake by the immobilised cells is used to measure the rate of photosynthesis; this can be done simply by observing the colour change of hydrogencarbonate indicator, either by eye or using a colorimeter.

SAPS - Photosynthesis with Algal Balls - SlideShare

This kit, which is based on one previously supplied by (SAPS), allows students to investigate photosynthesis semi-quantitatively using algae immobilised in calcium alginate.

Photosynthesis with algal balls ..

In this experiment, single celled algae are grown into a concentrated culture. The concentrated algae are then immobilised in a jelly-like substance, creating equal amounts of photosynthetic material in each sphere. Using a pH indicator, we can measure the rate of photosynthesis and the effect of variable contributing factors.
The experiment can be recreated in the classroom using created by the University of Reading. This activity was adapted from a resource developed through the Science and Plants for Schools (SAPS) programme. The original resource and others supporting biology education can be downloaded for free from the SAPS website: