Science & Art 2nde session SVT: Lichen Art

Source : http://www.barelyimaginedbeings.com/2013_02_01_archive.html

Pb: Lichens are amazing and beautiful organisms. What can we learn about them? Work session objectives 1- Watch the video from Natural History Museum and answer the five questions. 2- Look at rocks and tree branches picked up in our region and take a photo of it showing different kinds of lichens. Try to get an artistical picture! 3- Use the identification key to give the name of the species you found. 4- Observe symbiotic relationship between alga and fungus in microscope. 5- Write a short text to explain lichenic symbiosis & the link between lichen and air quality. Scientific report: 3 of you will be chosen randomly to prepare a short video report about lichens with an ipad. This group will present his work to the others during the last 15' and will have to use props given by the teacher (3 different lichens, a picture of lichen in cross-section). No more than 1'30 for the video but no less than 1'. In a group, you have to cooperate (a cameraman and 2 reporters sharing time speaking). Organisation: in group of 3 / for 1h30 NB : don't forget to save your work on a memory stick in order to print it for the exhibition! Resources

document 1: video from Natural History Museum http://www.nhm.ac.uk/nature-online/species-of-the-day/biodiversity/climate-cha nge/xanthoria-parietina/

document 2: Air quality survey What is air pollution? Much of the air pollution in Britain today is largely invisible and is difficult to detect, although you may be able to smell the pollutants from car exhausts, farmyards and heavy industry. These include ammonia and oxides of nitrogen. Although nitrogen is essential for the growth of all living organisms, too much nitrogen can cause problems. So what it all has to do with lichens? Nitrogen can stimulate the growth of some plants and fungi but stop others from developing. In our survey we were looking for lichens that are known to grow particularly well when they are close to sources of ammonia, as well as lichens that do not like excessive nitrogen in any form. Lichens are well known for their sensitivity to air pollution, which is why they are being used in our survey.

document 3: illustration of lichen morphology & mutually beneficial relationship

Questions about the video 1) Why is the group of volunteers so interested in lichens? a) ...because they want to harvest lichens for cooking

c) ...because lichens can give information about weather forecast

b) ...because lichens can give information about air quality

d) ...because lichens are pollution sensitive organisms

2) What are lichens? a) Lichens are special mushrooms

c) Lichens are plants that grow up on trees and rocks

b) Lichens are both fungi and algae living together

d) Lichens are an example of symbiosis

3) Why can we say that symbiosis is a mutually beneficial relationship? a) ...because each organism could have grown separately

c) ...because fungus can take advantage of alga's photosynthesis

b) ...because alga is sheltered in a constant and moist atmosphere

d) ...because fungus can eat alga if it's hungry

4) Xanthoria produces a molecule that gives it protection against UV: which one? a) Oenobiol

c) Ozone

b) Parietina

d) Palatina

5) In what environment does this lichen grow? a) ...in lot of places because it's a nitrogen tolerant lichen

c) ...in trees, rocks, roof slates well exposed to sun

b) ...in pollution free environement

d) ...in shade old walls

Moreover... ...The higher is the number of lichen species you can find, the healthier is the environment!