Digestion prac

and any other non-chem subjects.
Post Reply
User avatar
bindibadgi
Posts: 293
Joined: 13 May 2009, 09:37
Suburb: Kensington Park
State/Location: SA

Digestion prac

Post by bindibadgi »

Hiya,

a cheap & cheerful tip for digestion & absorption pracs....instead of dialysis tubing, you can use tiny zip-lock bags.

Livingstone International have them in all sizes, 40mm x 75mm $3.50 for a box of 1000, 50mm x 75mm $3.65 for a box of 1000.
They're semi-permeable & the kids don't have trouble like they do with the dialysis tubing :clap3:
bindibadgi
Jen2
Posts: 23
Joined: 01 May 2012, 09:48
State/Location: WA

Re: Digestion prac

Post by Jen2 »

wow! thanks for the tip, will try that next year, much cheaper
User avatar
rae
Posts: 1045
Joined: 31 May 2006, 10:00
School: Oxley College
Suburb: Burradoo
State/Location: NSW

Re: Digestion prac

Post by rae »

Do you mean for osmosis and diffusion??
User avatar
lada
Posts: 1024
Joined: 29 Jun 2006, 10:00
State/Location: NSW

Re: Digestion prac

Post by lada »

We use dialysis tubing for digestion prac with starch and sugars.
Great tip. Will make life a lot easier.
Lada
User avatar
rae
Posts: 1045
Joined: 31 May 2006, 10:00
School: Oxley College
Suburb: Burradoo
State/Location: NSW

Re: Digestion prac

Post by rae »

Do you use enzymes??
User avatar
lada
Posts: 1024
Joined: 29 Jun 2006, 10:00
State/Location: NSW

Re: Digestion prac

Post by lada »

Yes, we use amylase to break down starch into simple sugars.
Use iodine to check for starch and benedicts to check for sugars.
Lada
User avatar
lada
Posts: 1024
Joined: 29 Jun 2006, 10:00
State/Location: NSW

Re: Digestion prac

Post by lada »

Bindibadgi,
would you have catalogue number for those bags. Cannot find them
Thanks,
Lada
User avatar
fibreweb
Posts: 620
Joined: 20 Jul 2006, 10:00
School: Oxley High School
Suburb: Tamworth
State/Location: NSW

Re: Digestion prac

Post by fibreweb »

Freezer bags from the supermarket work also.
Even cheaper
User avatar
bindibadgi
Posts: 293
Joined: 13 May 2009, 09:37
Suburb: Kensington Park
State/Location: SA

Re: Digestion prac

Post by bindibadgi »

40 x 75 cat # is BPEZ040X075
50 x 75 cat # is BPEZ050X075

Do a search for 'zip-lock' & it'll show all the sizes...the biggest is 360mmx x400mm! :w00t:

Ditto what Lada said too, we get the kids to set up 3 bags: glucose, starch, starch+amylase all in beakers of water....then test for sugar & starch with the benedict's & iodine straight away, & 24 hours later (I always spike the beakers with a little glucose too of course :wink2: )

A cute little visual demo to do while they're getting their bags & beakers set up is to fill a bag with some starch solution & pop it in a beaker of diluted iodine. Within 10-15 mins the starch in the bag's turning blue-black, but the iodine in the beaker stays the same.
bindibadgi
User avatar
carolmay
Posts: 13
Joined: 24 Mar 2011, 14:01
State/Location: NSW

Re: Digestion prac

Post by carolmay »

Thank you will take that on board, l am new to this site but am loving reading all your ideas and saving a heap of them.
User avatar
nickykinz
Posts: 271
Joined: 02 Feb 2009, 12:53
Job Title: Lab Assistant
School: St Augustine's College
Suburb: Augustine Heights
State/Location: QLD

Re: Digestion prac

Post by nickykinz »

HI guys
I tried this out for the prac we do, with starch and glucose solution inside the dialysis tubing, in a beaker of iodine solution. Iodine moves into the tubing, glucose moves out. With the snap lock bags the starch/iodine bit worked really well but the glucose didn't transfer at all. I was using just some Hercules ones from the supermarket rather than Livingstones ones. I even left it over night and no glucose was detectable. Is it just that the bags are different?
Nicky
;)
St Augustine's College
Augustine Heights, QLD 4300
User avatar
lada
Posts: 1024
Joined: 29 Jun 2006, 10:00
State/Location: NSW

Re: Digestion prac

Post by lada »

Could be. For this to work they have to be permeable (semi-permeable).
Lada
User avatar
nickykinz
Posts: 271
Joined: 02 Feb 2009, 12:53
Job Title: Lab Assistant
School: St Augustine's College
Suburb: Augustine Heights
State/Location: QLD

Re: Digestion prac

Post by nickykinz »

So the glucose definitely works with the Livingstone ones? Maybe I'll have to order some. If I can get that bit to work it is so much easier than the dialysis tubing.
Nicky
;)
St Augustine's College
Augustine Heights, QLD 4300
User avatar
smiley
Posts: 1398
Joined: 20 Nov 2006, 10:00
State/Location: QLD

Re: Digestion prac

Post by smiley »

Hey guys - I have done this with freezer bags, not zip-lock bags! Not to say that the zip-locks don't work, just that the freezer bags do work, especially for the starch/iodine exp.
Cheers, K 8-)
User avatar
Labbie
Posts: 3234
Joined: 28 Nov 2006, 10:00
Job Title: Retired
Suburb: At Home
State/Location: NSW

Re: Digestion prac

Post by Labbie »

Just bumped this page again.
Regards Labbie

Lab Manager/Lab Tech, mind reading etc etc
Now retired :wub:
User avatar
remlap12
Posts: 340
Joined: 26 Jun 2014, 12:23
State/Location: NSW

Re: Digestion prac

Post by remlap12 »

Thanks Labbie
Regards
remlap12
science support and problem solver :mail:
Post Reply