Rate of Respiration in Yeast

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Biology Practicals and Revision Biology Tutor

8 жыл бұрын

Investigating the rate of respiration (anaerobic) in a single celled organism (yeast). Required A level biology practical.

Пікірлер: 85

@myearsgotyouthsystem8802 3 жыл бұрын

Your videos are amazing and clearly, you deserve more views

@enolaliv663 6 ай бұрын

1. Add 10cm^3 of 5% yeast suspension to three boiling tubes labelled A, B, C 2. Add 10cm^3 of 5% glucose solution to tube A, sucrose solution to tube B and maltose solution to tube C 3. Add three drops of Janus Green B indicator to each boiling tube and gently shake to mix the contents 4. Add a thin layer of liquid paraffin (2mm thick) to the top of each boiling tube 5. Leave the boiling tubes until the Janus Green B indicator has changed colour from blue to pink 6. Insert the bung in tube A and stand it in the water bath. The clip should be removed or open. Leave the tube to equilibriate for 5 minutes 7. Close the slip to seal the apparatus and mark the level of the meniscus 8. Use a ruler to mark another line 10mm higher than the miniscus 9. Start the stopclock and time how long it takes for the miniscus to move from its original positition to the 10mm line 10. Repeat 3 times 11. Work out rate of respiration of the different sugars by taking 1000 divided by the mean time for each sugar

@emschool1451 6 жыл бұрын

You are an absolute life saver! Thank you so much!! 👍😃

@biologypracticalsandrevisi8066 4 жыл бұрын

The fluid moves due to the yeast producing CO2 in anaerobic respiration. This increases the pressure inside the apparatus pushing the red liquid along the tube. You can tune the movement of the fluid to give an indication of the rate of anaerobic respiration.

@SaadKhan-tm9rx 4 жыл бұрын

Why r u not making more videos

@SaadKhan-tm9rx 4 жыл бұрын

Only this videos r enough for As paper 3

@estherchue1804 2 жыл бұрын

Ukkkukuul

@estherchue1804 2 жыл бұрын

U hi l oops

@gamingspotlight6194 3 жыл бұрын

Hi, I had three questions after watching the video, I would be so pleased if you could answer them for me .Why is the tap open when the apparatus is assembled? and why is the tap not closed until after 5 minutes after setting up? Why are no readings taken before the indicator changes to pink

@fidahaziz1046 4 жыл бұрын

i dont know if you will reply but is there a list of equipments used

@jesslacuesta8849 4 жыл бұрын

Hi! Is it possible for the sucrose to produce more co2 and have a faster rate given that it needs to be brokendown first into glucose by the enzyme coming from yeast? rather than the readily glucose?

@harrywarman6196 4 жыл бұрын

7:05 pause video for results table

@shiddy5458 3 жыл бұрын

Thanks have this as quarantine work

@Venus0Kets 2 жыл бұрын

What statistical test and graph would you use for the data?

@riviera443 4 жыл бұрын

Nice demo...

@innocentiasigudla5242 3 жыл бұрын

Thank you so much 😪😪

@omsingh8147 Жыл бұрын

what are the controlled variables in this experiment? thank you

@miniescapes2 4 жыл бұрын

Thanks you for this☺☺

@bonniekirk4446 2 жыл бұрын

Hi, can you use normal Benedict's without janus green B, what else can you use if you do not have Janus Green B?

@umarishaque3936 6 жыл бұрын

Excellent video, really helpful and well explained. Quick Question, instead of measuring how long it takes for the fluid to move up a set length of the tube (in this case 1 centimetre), would it also be possible to measure the length moved by the fluid in a set length of time?

@biologypracticalsandrevisi8066 6 жыл бұрын

Zylo gamer yes you could do that. Both ways will allow you to calculate a rate and it does work in aerobic conditions but not as fast. Bung and tube from any scientific school supplier.

@miniblueraven382 6 жыл бұрын

Zylo gamer hi

@monabey5254 6 жыл бұрын

Hi! i love your channel it has helped me a lot. What I want to know is which practicals do I have to perform if I am giving my AS and A2 together. It will be of great help if you can list me the practicals......... no one is helping me out I have tried reaching out to people and I am doing this all alone at home without coaching or any help because I can't afford it and I really need this.

@biologypracticalsandrevisi8066 6 жыл бұрын

Mona Bey The 12 practicals in my channel are the 12 required by AQA exam board For A2 Biology. Learn them all. Good luck. Doing AS and A2 biol on your own at home is tough.

@monabey5254 6 жыл бұрын

yeah... tell me about it but i am in zone 4 and i am from pakistan so some experiments arent usually performed here because they are too sophisticated.

@ezraaigbe1211 7 жыл бұрын

where do you get the bung and capillary tube

@peacexoom4936 6 жыл бұрын

Thank you, very helpful! :)

@dylanh3620 6 жыл бұрын

What fluid are you using to measure the distance?

@biologypracticalsandrevisi8066 6 жыл бұрын

You can use any non toxic coloured fluid. I used water with red food colouring.

@rebeccaolson9669 4 жыл бұрын

Where did you order the capillary u tubing from?? Im planning on doing this experiment for my ib Bio class, but I can't find the tubing anywhere... Thanks

@biologypracticalsandrevisi8066 4 жыл бұрын

Rebecca Olson you can buy the straight capillary tubing and bend it yourself. Flint glass is easier to bend as opposed to borosilicate glass (Pyrex) which is more difficult to work with. A good technician may know how to do it or you can find info and demonstrations on the internet.

@DicedDwebble 3 жыл бұрын

Hi, would it be possible to do the same experiment but with the named variable as temperature instead of type of sugar in a future video? Thanks

@biologypracticalsandrevisi8066 3 жыл бұрын

Yes.

@la6773 2 жыл бұрын

can i replace janus green b with methylene blue?

@MultiBinman1 7 жыл бұрын

Is it possible to do an experiment similar to this but in aerobic conditions? And what did you put in with the yeast to get that brown solution? we will be given 15g only to work with

@MultiBinman1 7 жыл бұрын

or can i just put the yeast into the sugar solution?

@biologypracticalsandrevisi8066 7 жыл бұрын

The yeast is that colour naturally. It is simply a suspension of yeast in warm water with a little glucose added. Yes it would work in aerobic conditions.

@MultiBinman1 7 жыл бұрын

+Biology Practical Activities and Revision Thank you for your fast reply! To do it in aerobic conditions I do the experiment without adding the oil correct? and I'm not sure our school will provide us with janus so I doubt I will use that either

@biologypracticalsandrevisi8066 7 жыл бұрын

Just do it without oil or janus green. It will work fine.

@Mary-wr4uv 3 жыл бұрын

very useful video and very nicely explained! But please change the cameraman.... it's a bit a pitty....

@faisal6167 4 жыл бұрын

Thank j madam

@doublestuffedramenoreo6798 4 жыл бұрын

Great video! But does anyone know why my tube fails to turn pink even after 20 minutes?

@biologypracticalsandrevisi8066 4 жыл бұрын

Double Stuffed Ramen Oreo is the oil layer thick enough to stop oxygen. Are the yeast active and at a good temperature e.g. 40 and is it brewers yeast as opposed to bakers yeast. Brewers works much better.

@yaelkohen7477 7 жыл бұрын

how long does it take for the color to turn pink?

@biologypracticalsandrevisi8066 7 жыл бұрын

It should go pink in around 10 mins as long as the yeast is active at 40C with some glucose first. Also use brewers yeaat instead of bakers. It works much better.

@yaelkohen7477 7 жыл бұрын

thanks!

@noorbaaghil3015 5 жыл бұрын

What is the graph for this experiment

@nashaadrina9042 4 жыл бұрын

Whats the independant variable?

@biologypracticalsandrevisi8066 4 жыл бұрын

Nasha Adrina in this case it is the type of sugar.

@nadineahmed1249 4 жыл бұрын

Is green dye the same as janet green indicator?

@biologypracticalsandrevisi8066 4 жыл бұрын

Nadine Ahmed Sorry for the late response but the indicator is Janus Green.

@biologypracticalsandrevisi8066 4 жыл бұрын

Nadine Ahmed it was once used in breath tests by the police to detect ethanol.

@mateuszkowalski6452 6 жыл бұрын

Can you tell me what was the red liquid used in the capillary tube? By the way, is there anywhere an access to all of the results received in your experiment? They would be really helpful, serving as comparative values for my own results. Thanks in advance.

@biologypracticalsandrevisi8066 6 жыл бұрын

Mateusz Kowalski you can use any red liquid. Ink and food colouring are good. I’ll work in getting the results on here. I thought they were on the end of the clip bug maybe not all of them.

@mateuszkowalski6452 6 жыл бұрын

Okay, by the way, was the experimental set-up picture taken from the Internet or you made it by yourself? If it was self-made, could you give me an access to it? I would appreciate it.

@jesslacuesta8849 4 жыл бұрын

Is it the tube C with 5% of maltose remained blue? And tube A and B turned pink.

@biologypracticalsandrevisi8066 4 жыл бұрын

Jess Lacuesta they should all go pink indicating that conditions are anaerobic.

@jesslacuesta8849 4 жыл бұрын

@@biologypracticalsandrevisi8066 thanks

@attya186 6 жыл бұрын

hi there, is there a respirometer experiment available?

@biologypracticalsandrevisi8066 6 жыл бұрын

Sorry not at the min. If you google around I’m sure you’ll find one. I will do one at some point.

@Zezemint 6 жыл бұрын

How did we get the yeast suspension? What was needed to prepare the yeast suspension?

@biologypracticalsandrevisi8066 6 жыл бұрын

Zezemint it is just dried Brewers yeast in warm water.

@Zezemint 6 жыл бұрын

Is it correct to say that paraffin ONLY prevents O2 diffusion, and not CO2 diffusion? CO2 technically is a bigger molecule, so why can it pass through paraffin while O2 cannot?

@biologypracticalsandrevisi8066 6 жыл бұрын

Zezemint it reduces not completely prevents gas diffusion. As CO2 is being produced at quite a high rate by the yeast, the very steep concentration gradient results in more CO2 escaping.

@DJKaiChannelNB 6 жыл бұрын

why have you got a water bath?

@biologypracticalsandrevisi8066 6 жыл бұрын

Kai it maintains a constant temperature so that in this case temperature doesn’t become a confounding variable. You could also vary the temperature of the water bath if you wanted to investigate the affects of temperature on respiration rate.

@user-wt6yo3ql1z 5 жыл бұрын

Why does the red liquid move? What is the red liquid for? Is it because of pressure change?

@beziik2357 5 жыл бұрын

It is because of the production of CO2 by the yeast.

@Zezemint 6 жыл бұрын

what is the name of this experiment?

@biologypracticalsandrevisi8066 6 жыл бұрын

Zezemint no real name though it is a type of respirometer really.

@Zezemint 6 жыл бұрын

what is the colored fluid? why was it chosen?

@biologypracticalsandrevisi8066 6 жыл бұрын

Zezemint it is just food colouring. You can use ink too. It doesn’t matter what you use but the colour makes it easier to see.

@Zezemint 6 жыл бұрын

and what is the function of the short tube and clip?

@Zezemint 6 жыл бұрын

ie, to prevent air from entering, why not just have a bung without that opening for the short tube?

@minhross1476 6 жыл бұрын

what is the hypothesis for this practical

@biologypracticalsandrevisi8066 6 жыл бұрын

no no Well there isn’t really an hypothesis. But you could predict the best sugar or optimum temperature and put it to the test so the hypothesis could be: The monosaccharide glucose will produce a faster rate if anaerobic respiration in yeast than the disaccharides Maltose and Sucrose.

@minhross1476 6 жыл бұрын

fantastic video, very helpful

@RachelJ715 6 жыл бұрын

There will be no difference in rate of respiration in yeast caused by changing respiratory substrate to a monosaccharide or disaccharide