In this post we are going to discuss the evolution of the column in the fifth (the last) week,
The surface is more green compairing with the fourth week, due to the growth of microalgae and cianobacteria (aerobic photosinthetic). Furthermore in this part of the column there are more bubbles because there is more oxygen than the previous week.
In the middle of the column the pink is more intense because the anaerobic photosintetic bacteria have been producing more sulphure. For that reason when we hit the column in the table the smell is worse than the last week.
The part of the column that is reached by the sunlight has a brown colour while the otherside is black, due to the presence of heterotrophic bacteria which oxidate iron, in the brown part.
To sum up, comparing with the prediction in the first post we can conclude thet,
1. Halophilic bacteria haven't appeared apparently.
2.Cianobacteria (autotrophic bacteria) have grown in the surface of our column, as we expected.
3.Heterotrophic microorganisms have appeared too (they oxidate iron).
4.Microorganisms which can assimilate the sulfur have appeared.
Winogradsky column lab page!
Welcome to the Winogradsky column lab page! Students from the Departments of Biological Applications and Technology, University of Ioannina and Icthyology and Aquatic Environment, University of Thessaly, Greece and the Microbiology course, Faculty of Sciences, University of Cádiz, Spain, discuss their findings on Winogradsky columns they constructed!
If you want to add a post, please feel free to contact the blog administrators (Hera Karayanni, Sokratis Papaspyrou or Kostas Kormas)!
Καλωσορίσατε στη σελίδα των Winobloggers! Διαδικτυακός τόπος συνάντησης φοιτητών, φοιτητριών και διδασκόντων δύο Τμημάτων από την Ελλάδα: Tμήμα Βιολογικών Εφαρμογών και Τεχνολογιών, Παν/μιο Ιωαννίνων και Τμήμα Γεωπονίας, Ιχθυολογίας και Υδάτινου Περιβάλλοντος, Παν/μιο Θεσσαλίας και ενός από την Ισπανία: Σχολή Θετικών Επιστημών, Πανεπιστήμιο του Cadiz. Παρακολουθούμε, σχολιάζουμε, ρωτάμε, απαντάμε σχετικά με τα πειράματά μας, τις στήλες Winogradsky!
Bienvenidos a la pagina web de los Winobloggers! Aquí los estudiantes y profesores de dos departamentos griegos, el Departamento de Aplicaciones y Tecnologías Biológicas de la Universidad de Ioannina y el Departmento de Agricultura, Ictiología y Sistemas Acuáticos de la Universidad de Thessalia, junto con los estudiantes de Microbiología de la Facultad de Ciencias en la Universidad de Cádiz, se reúnen para observar, comentar, preguntar y responder a preguntas relacionadas con nuestro experimento, la columna Winogradsky.
Unfortunately we cannot see the photos. Can you upload them again?
ReplyDelete"1. Halophilic bacteria haven't appeared apparently."
How could you tell if you have halophilic bacteria?
"2.Cianobacteria (autotrophic bacteria) have grown in the surface of our column, as we expected."
Great!
"3.Heterotrophic microorganisms have appeared too (they oxidate iron)."
What types of heterotrophic bacteria do you know? Among other hteretrophic groups the ones that use iron are the iron reducers, not iron oxidisers. The latter are usually autotrophs.
"4.Microorganisms which can assimilate the sulfur have appeared."
All microorganisms need to assimilate one way or the other S. The pink coloured bacteria are purple sulfur bacteria. They are photosynthetic bacteria that use hydrogen sulfide (H2S) instead of H2O.
I hope the experiment helped you to learn some things on the complexity of microbial metabolisms.