Joan in GE Posted November 17, 2011 Share Posted November 17, 2011 Hello to all using M/L Biology (Macaw) Book and Lab manual.... Another mom and I have been exchanging questions and she proposed starting a support group to share tips and tricks we've learned....so voila... It's so helpful to know when we can substitute materials as well - and sometimes more fun... I thought if people put the chapter in the heading of the post, it would help people identify more easily where an answer might be... After time is spent chasing down some detail that wasn't well-explained, it's fun to be able to share it... Any other ideas/suggestions are welcome - the value of the hive is building together... Joan Quote Link to comment Share on other sites More sharing options...
Joan in GE Posted November 17, 2011 Author Share Posted November 17, 2011 An example :001_smile: In this lab it suggests using glucose test strips to test for the presence of glucose... Since I didn't want to open my very hard to get (over here) pack of glucose test strips just for one strip (because they go bad once the pack is opened), I did a quick search online for another way of testing for glucose... and found that I could put some drops of Benedict's reagent in the glucose solution in a test tube, heat it in a water bath and at a certain temp, it flash changed into a bright yellow-orange colored solution... Joan Quote Link to comment Share on other sites More sharing options...
Joan in GE Posted November 17, 2011 Author Share Posted November 17, 2011 (edited) Another example It calls for chromatography paper...we used filter paper...you can even use coffee filters as it explains on this page under tips. Also - you need red leaves (ETD - faulty info before - see Debbie's post below) Also - here are the answers for the colors - both will show a green pigment, but the green leaf may produce a more prominent green band... Green - chlorophyll...chlorophyll a generally appears blue-green. chlorophyll b appears yellow-green. Yellow orange pigments are carotenoids. Purple-red pigments are anthocyanins. Yellow-brown pigments are xanthophylls... We have just done this one but are going to redo it and rub more of the leaf onto the paper as the results were very weak... Joan Edited November 17, 2011 by Joan in Geneva Quote Link to comment Share on other sites More sharing options...
Joan in GE Posted November 17, 2011 Author Share Posted November 17, 2011 We bought a shiitake mushroom spores... Warning - these take 6 months or more to produce anything... You need to also have access to fresh logs from certain kinds of trees, a drill to drill holes in the logs, etc. BUT I can't wait to eat them :001_smile: The lab manual says there are some kinds of kits available that will grow in 10 days. It takes time to get the kits too, just to count that into your lab prep so you don't think you can just open the lab manual and do the experiment. :001_smile: Joan Quote Link to comment Share on other sites More sharing options...
Mom22ns Posted November 17, 2011 Share Posted November 17, 2011 Another example It calls for chromatography paper...we used filter paper...you can even use coffee filters as it explains on this page under tips. Also - you need red leaves (not ones that have changed due to autumn), so it is better to do this a bit earlier in the season... Also - here are the answers for the colors - both will show a green pigment, but the green leaf may produce a more prominent green band... Green - chlorophyll...chlorophyll a generally appears blue-green. chlorophyll b appears yellow-green. Yellow orange pigments are carotenoids. Purple-red pigments are anthocyanins. Yellow-brown pigments are xanthophylls... We have just done this one but are going to redo it and rub more of the leaf onto the paper as the results were very weak... Joan Actually, red leaves that have changed colors will work too, you will get a different pigment though. I looked up the lab on the internet then redid it following those instructions instead of the ones provided in the Pearson Lab manual. Much more accurate results. Then were were able to actually calculate the Rf values and use a table to identify the pigments that were in the leaves. Quote Link to comment Share on other sites More sharing options...
Joan in GE Posted November 17, 2011 Author Share Posted November 17, 2011 (edited) Actually, red leaves that have changed colors will work too, you will get a different pigment though. I looked up the lab on the internet then redid it following those instructions instead of the ones provided in the Pearson Lab manual. Much more accurate results. Then were were able to actually calculate the Rf values and use a table to identify the pigments that were in the leaves. Thank you so much - the thread is useful already! ETA - here is one site that has it....http://www.phschool.com/science/biology_place/labbench/lab4/intro.html Joan Edited November 18, 2011 by Joan in Geneva Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.