A-level BIOCHEMICAL TESTS- test for starch, reducing sugars, non-reducing sugars, proteins, lipids

Поділитися
Вставка
  • Опубліковано 7 лют 2025

КОМЕНТАРІ • 154

  • @ecave3435
    @ecave3435 Рік тому +42

    I left my book at school, thank you

  • @BigRedKanga
    @BigRedKanga Рік тому +8

    I am a private student and self studying looking for a complete career change, I have found your videos that have been an amazing complement to the AQA text book. I watch your videos before studying the topic and it just makes so much more sense. Being a private student, it is tough to get into a lab, so thank you for these brilliant videos. I understand how much time they must take to compile. Thank you!

    • @MissEstruchBiology
      @MissEstruchBiology  Рік тому +1

      You are so welcome! I'm so pleased they are helping you 😊😊

  • @irshaadali795
    @irshaadali795 3 роки тому +32

    I was sick from school and I miss this lab experiment but your video help me to get caught back up and understand everything. Thank you so much and keep being you.

  • @edb3422
    @edb3422 4 роки тому +15

    Who is mean enough to dislike these? They are amazing and so helpful, Thankyou so much 🙏

    • @MissEstruchBiology
      @MissEstruchBiology  4 роки тому +4

      haha thank you 😊
      So pleased you find them helpful. Good luck with your exams!

  • @drhaneenali
    @drhaneenali 4 роки тому +22

    thank you so much for this video Miss Estruch!! the bit about why the colour change starts at the top is so cool :) and the practical video is so helpful since we can't do practicals at the moment :(

    • @MissEstruchBiology
      @MissEstruchBiology  4 роки тому +2

      Really glad you found it helpful as a replacement for actually doing the practical.

  • @kunchaako3848
    @kunchaako3848 3 роки тому +8

    I love how you cover every spec point and put the mark scheme answers in bold. Thank you so so much!!

    • @MissEstruchBiology
      @MissEstruchBiology  3 роки тому +2

      Thank you! So glad you find it helpful the way it's presented. I try to keep it concise and linked to marking points to help with efficient revision.

  • @ranix4866
    @ranix4866 4 роки тому +27

    This channel is underrated
    You are legit the eliot rintoul of A level biology
    Great vid thank u!

    • @MissEstruchBiology
      @MissEstruchBiology  4 роки тому +4

      Thank you so much 😊😊
      Hope the videos help your studies!!

  • @triciahardman5867
    @triciahardman5867 2 роки тому +3

    Excellent - great to share with students who have either not done or have forgotten food tests!

    • @lc4979q
      @lc4979q 2 роки тому +1

      i know you commented this ages ago, but do we need to add water to the sample along with benedicts?

  • @mjdalmoalem4871
    @mjdalmoalem4871 4 роки тому +6

    thanks miss Estruch, you are amazing. I was so confused, but when I watched your video, you clarified everything

  • @KagisoLenyeletse-k6f
    @KagisoLenyeletse-k6f 8 місяців тому +1

    This woman is out here saving lives😭

  • @AG-ql1sy
    @AG-ql1sy 3 роки тому +9

    should be illegal to explain things as good as you do aha, some serious talent for teaching there

  • @user78832
    @user78832 Рік тому

    Words can’t describe how much I love this women

  • @__k.c.e.l.l.a8007
    @__k.c.e.l.l.a8007 4 роки тому +7

    Thank you so much...i even learnt beyond my textbook

  • @florencesk2296
    @florencesk2296 9 місяців тому +1

    Thank you so much, for some of us who are writing GCE.

  • @aymanali6402
    @aymanali6402 3 роки тому +3

    thank you so much for this video Miss Estruch

  • @priyajoseph144
    @priyajoseph144 10 місяців тому +1

    Great video, thanks so much for all the tests in one and the final summary!!!

  • @Aisia-uc7ol
    @Aisia-uc7ol 9 місяців тому +1

    I did experiment but I didn't understand coz our lab supervisor didn't explain it properly but thanks for the help from this video.

  • @wekesastephen
    @wekesastephen 4 місяці тому +1

    Thanks for making me understand better

  • @ShanonLady
    @ShanonLady 3 місяці тому +1

    She's so amazing thanks a lot accept greatings from Cameron 🇨🇲

    • @MissEstruchBiology
      @MissEstruchBiology  3 місяці тому

      ahh thank you!!! Wow watching in Cameroon 🇨🇲 amazing

  • @callummullaney2353
    @callummullaney2353 3 роки тому +1

    Hello Miss!!!!! Thank you so much for the video :)

  • @sarahsalman4114
    @sarahsalman4114 Рік тому

    Excellent video for quick revision... thanks!

  • @priyabharti3812
    @priyabharti3812 11 місяців тому +1

    Thank you for amazing video 🙏🏻❤

  • @FalmyAlex
    @FalmyAlex 7 місяців тому

    The video is mazing so i have downloaded it. Thank u very much.

  • @RennesPuffs10
    @RennesPuffs10 7 місяців тому

    This is extra work given by my teacher, and wooh 😅 this is hard im currently in year 8 and this helped tyssm !!❤❤

  • @ammosatti8988
    @ammosatti8988 Рік тому

    Hi from Pakistan, thanks for saving me. I have shared your this consolidated biochemical test video with my FSc ( high school's students) as I was guilty I couldn't deliver them enough in my practical class.
    Keep up good work . N I would like to suggest u a few more topics along with textbook material that needs 3D demonstration and practical demonstration. If u appreciate it, u may create a video on it. Stay blessed ❤

  • @samirkouzi
    @samirkouzi 2 роки тому +2

    Lovely work, this will be helpful for my tests.
    Thanks!
    ~Mustafa Dafalla.

  • @tinachinyuka126
    @tinachinyuka126 10 місяців тому

    Wow this is helpful thanks so much God bless you abundantly ❤❤

  • @sophieramshaw8082
    @sophieramshaw8082 2 роки тому +4

    Do we need to know why the colour change occurs at the top of the solution first for the exam ? is that on the spec ? Amazing videos ! I'm watching them all before my exams this year , I haven't been able to go to my lessons but have still got As thanks to you !!

    • @MissEstruchBiology
      @MissEstruchBiology  2 роки тому +1

      Hey not on the spec, but an example of an application question

  • @Anonymous-mg9nd
    @Anonymous-mg9nd 2 роки тому +1

    Thanks a lot Miss. It helped a lot...

  • @shahilclips68
    @shahilclips68 10 місяців тому

    can please elaborate on how much you're adding like how many
    drops of acid

  • @jencyauriavales4278
    @jencyauriavales4278 2 роки тому +2

    Just wondering, were we supposed to know oil is a lipid? Just a bit concerned because I didn't really know that
    Thank you!

    • @anittajose
      @anittajose 2 роки тому +1

      yes, it's an unsaturated fat

  • @jasonsingh9698
    @jasonsingh9698 2 роки тому +1

    Hi Miss, do we have to know specific measurements of how much reagent we have to add. Like do we have to say “add 2cm3 of Benedict’s reagent to the test tube”

  • @pakohlomani4100
    @pakohlomani4100 3 роки тому +3

    Hi Miss Estruch .Firstly thanks for the fascinating videos .I would like to ask about the negative result on lipids .Hmm what's the negative result

    • @MissEstruchBiology
      @MissEstruchBiology  3 роки тому

      The negative would be no white emulsion. There isn't a set colour to describe as ethanol is colourless.

    • @pakohlomani4100
      @pakohlomani4100 3 роки тому +1

      Okay thanks

  • @AS-qi2lq
    @AS-qi2lq 3 роки тому +4

    Thanks so much for the video! Really helpful. I have a small doubt if you could answer. What exactly is the reagent in the lipid test? Is it ethanol or distilled water?

    • @MissEstruchBiology
      @MissEstruchBiology  3 роки тому +1

      There isn't a single reagent, both are required and both are worth separate marks in the exam.
      Hope that helps 😊

    • @AS-qi2lq
      @AS-qi2lq 3 роки тому +1

      Thank you!

    • @AS-qi2lq
      @AS-qi2lq 3 роки тому

      And also one more thing, is emulsion and turbidity the same thing?

    • @MissEstruchBiology
      @MissEstruchBiology  3 роки тому

      no, turbidity is a measure of cloudiness, but emulsion is the technical name for a fine dispersion of minute droplets of one liquid in another in which it is not soluble or miscible.

  • @sofiasolanki7839
    @sofiasolanki7839 4 роки тому +3

    Hi Miss Estruch,
    Firstly thank you for these videos, they're amazing!!
    I was just wondering if we need to know the names of the 'acid' and 'alkali' in the tests- like non-reducing sugars?

    • @MissEstruchBiology
      @MissEstruchBiology  4 роки тому +1

      Hello,
      No, its not specified on the specification. Just need to know it is 'boil in acid' and then add alkaline to make slightly alkaline as that is required for Benedicts

    • @sofiasolanki7839
      @sofiasolanki7839 4 роки тому +1

      @@MissEstruchBiology Ahh ok, thanks so much!

  • @9xelle
    @9xelle 3 роки тому +5

    Hi :)
    I'm confused. In my book it says that for the buiret test for protiens that you need to add Sodium hyroxide solution to the test sample, then add Copper(II) sulfate solution.
    I'm not sure, in an exam situation, what to put to get the marks. Your explanation or the textbooks, OR is it the same thing?
    Thanks :))

    • @MissEstruchBiology
      @MissEstruchBiology  3 роки тому +1

      Hello,
      Those are the chemicals that biuret is made of, so you can say either in the exam 😊

  • @AS-mw6pw
    @AS-mw6pw 3 роки тому +3

    Hi Miss, for the test for proteins, do we just need to say ‘add Biuret solution’, because I was doing some questions from the revision guide and in the answers it says ‘add a few drops of sodium hydroxide solution, then add some copper (II) sulphate solution’.

    • @MissEstruchBiology
      @MissEstruchBiology  3 роки тому +1

      Hello,
      For AQA they accept either answer, so I always say biuret as it's less to remember 😊

    • @AS-mw6pw
      @AS-mw6pw 3 роки тому +1

      @@MissEstruchBiology ok thanks Miss

  • @CatherineVanArsdale
    @CatherineVanArsdale 6 місяців тому

    How do you dispose of the material following the tests? Any particular way?

    • @MissEstruchBiology
      @MissEstruchBiology  6 місяців тому

      Ethanol- we keep this sample and the technician distils it.
      All the others are washed down the sink as they don't have the harmful to environmental haz card

  • @SharifahNamuwonge
    @SharifahNamuwonge 6 місяців тому

    Thanks for the info

  • @dcarbou
    @dcarbou 3 роки тому +2

    greatest channel of all time

    • @MissEstruchBiology
      @MissEstruchBiology  3 роки тому

      ☺☺ aww you're too kind, thank you!!! Hope the videos are helping you.

  • @-nb1fm
    @-nb1fm 6 місяців тому

    thank you

  • @alexiaplacinta5468
    @alexiaplacinta5468 3 роки тому +1

    Very helpful

  • @tanvirdipsheikh1514
    @tanvirdipsheikh1514 2 роки тому +1

    Hi, miss! What changes would you make to obtain semi-quantitative results, please?

  • @sarahkreidly6732
    @sarahkreidly6732 2 роки тому

    Whats the use of distilled water in tests ?do we use distilled water As a control? To compare other tubes with its results

    • @MissEstruchBiology
      @MissEstruchBiology  2 роки тому

      yes that's it! It's the control to show it was the test substance causing any changes seen

  • @Sweetroses-v4n
    @Sweetroses-v4n 4 місяці тому

    Hi at 5:56 exactly why does it say for reducing sugars that copper sulfate is reduced to form copper oxide, when a molecule gains oxygen should it not be considered oxidised!

    • @Phosphoenoylpyruvate
      @Phosphoenoylpyruvate 4 місяці тому

      Yeah it doesn’t make any sense. I thought the reducing sugars donate electrons to copper IONS reducing them and forming a coloured precipitate

  • @comixgamez3390
    @comixgamez3390 3 роки тому +2

    do we not need to specify which acid and alkaline to add for the non reducing sugar test?

    • @MissEstruchBiology
      @MissEstruchBiology  3 роки тому

      Hello,
      For AQA it doesn't specify that you need exact names of the acids and alkaline.

    • @comixgamez3390
      @comixgamez3390 3 роки тому +1

      @@MissEstruchBiology Okay thank you very much, I looked them up and they arent hard to remember.

  • @Naveenbabuborugadda
    @Naveenbabuborugadda 9 місяців тому

    Which acid and alkali have you taken for the non reducing sugars?

  • @miketyson-g6b
    @miketyson-g6b Рік тому

    THANK you so much .

  • @aaronrajimon312
    @aaronrajimon312 3 роки тому +3

    Hello miss , I know this isnt part of the video , but im a 2 year a level student , i have my A LEVEL paper 1 exams in about 3 days , should i go through AS paper and A LEVEL PAPER , or should i just go through a level past paper

    • @MissEstruchBiology
      @MissEstruchBiology  3 роки тому +1

      Hello,
      It depends how much time you feel you have. The A-level papers should be a priority, but the AS papers do have a lot of really good maths questions and practical questions in too that will be helpful. If you have time, then yes I would recommend you do.
      Good luck!

    • @aaronrajimon312
      @aaronrajimon312 3 роки тому +1

      @@MissEstruchBiology ok thank you soo much :)

  • @idontknowwhattonamethis75h82
    @idontknowwhattonamethis75h82 2 роки тому +1

    Hey miss, is it fine if i use some of the picture of your videos for my flashcards, non-commercial use. I would really like to take pictures of your tests and a few diagrams for my anki deck

    • @MissEstruchBiology
      @MissEstruchBiology  2 роки тому +1

      Hey yeah of course, that sounds like a good way to make flash cards

  • @darrenpattison7674
    @darrenpattison7674 Рік тому

    I always thought Biuret was pronounced Bee-oooh-ray. Thats what I get from learning it by myself from a Textbook and no other input (until I discovered your channel of course) :)

  • @ell6311
    @ell6311 3 роки тому +1

    Do you know what Reducing sugars we have to learn for AQA are?

    • @MissEstruchBiology
      @MissEstruchBiology  3 роки тому +1

      glucose, fructose, galactose, maltose and lactose 😊
      Sucrose is non reducing

    • @ell6311
      @ell6311 3 роки тому

      @@MissEstruchBiology thank youuuu

  • @daltonbbosa7659
    @daltonbbosa7659 Рік тому

    Thanks for that madam biology am kyobs science because I knew what I was eating

  • @myrtle9681
    @myrtle9681 6 місяців тому

    Thanks for the contant

  • @TripexxGaming
    @TripexxGaming 3 місяці тому

    Wakhanda forever❤❤

  • @fergus3417
    @fergus3417 3 роки тому +2

    may i ask how is the starch orange in colour

    • @MissEstruchBiology
      @MissEstruchBiology  3 роки тому

      Starch is colourless. It is the iodine that is orange, and it turns blue/black in the presence of starch

  • @amttpassion9371
    @amttpassion9371 4 роки тому +5

    Hello. This video explained the biochemical tests really well, thank you! May I ask that I don't still get why the non-reducing sugar (sucrose) is not able to reduce the copper sulphate. Lactose and Maltose are also disaccharides, so how is this different to Sucrose, may I ask why aren't they non-reducing sugars. I hope that makes sense. Thank you Miss Estruch.

    • @MissEstruchBiology
      @MissEstruchBiology  4 роки тому +4

      Hello,
      Its because of the monomers sucrose is made of.
      Because it contains fructose, unlike the other two disaccharides, it forms a bond that prevents it from reducing Benedicts.
      Have a look at the pics in this link images.app.goo.gl/Nmo2ErcbUMPaURRS8
      Hope that helps 😊

  • @Top5-28
    @Top5-28 15 днів тому +1

    pls make the practical test doing video much faster, it was almost too slow for me to understand.

    • @MissEstruchBiology
      @MissEstruchBiology  11 днів тому

      hey, if you hit the settings button you can alter the speed you watch any video to make it slower or faster

  • @kamilaAhmedzai
    @kamilaAhmedzai 2 роки тому +1

    Hi Miss,
    just wondering about the test for protein, my textbook says to add sodium hydroxide and then copper ii sulfate and observe the color change. just wondering what I should write in an exam?

    • @MissEstruchBiology
      @MissEstruchBiology  2 роки тому +2

      that is a long description of the biuret test. Both would get a mark, but biuret is much quicker to write

    • @kamilaAhmedzai
      @kamilaAhmedzai 2 роки тому

      @@MissEstruchBiology Thank you soo much!!!

  • @shahriarkawsar5526
    @shahriarkawsar5526 Рік тому

    Thanks mam

  • @haabeel7702
    @haabeel7702 2 роки тому

    cheers

  • @jamilumusa8544
    @jamilumusa8544 5 місяців тому

    I thought lactose is a reducing sugar

  • @avelaw1361
    @avelaw1361 4 роки тому +2

    Hey

  • @Wojbest_YT
    @Wojbest_YT 9 місяців тому

    3:46 if you didn't have file explorer open you would have doxxed your self

    • @keetanjohal3559
      @keetanjohal3559 7 місяців тому

      Bit weird

    • @Wojbest_YT
      @Wojbest_YT 7 місяців тому

      @@keetanjohal3559 nah but her school logo was there im just saying

    • @keetanjohal3559
      @keetanjohal3559 7 місяців тому

      @@Wojbest_YT hahaha lmao join me i will find her school

    • @keetanjohal3559
      @keetanjohal3559 7 місяців тому

      @@Wojbest_YT Nvm she goes to woodford county high school for girls

    • @Wojbest_YT
      @Wojbest_YT 7 місяців тому

      @@keetanjohal3559 nah u cant that would be L rizz

  • @dinnahzulu3382
    @dinnahzulu3382 Рік тому +1

    ❤❤

  • @adamhilai5290
    @adamhilai5290 4 роки тому +1

    I hope to speak Arabic because I don't understand very clear

    • @MissEstruchBiology
      @MissEstruchBiology  4 роки тому

      ah sorry, I only speak English

    • @adamhilai5290
      @adamhilai5290 4 роки тому

      But can you explain for me food and it's constitunets

    • @adamhilai5290
      @adamhilai5290 4 роки тому

      Also digestion of starch

    • @adamhilai5290
      @adamhilai5290 4 роки тому

      @@MissEstruchBiology digestion of proteins and lipids

    • @adamhilai5290
      @adamhilai5290 4 роки тому

      @@MissEstruchBiology and activity of enzymes because I have exam tomorrow and I don't understand any thing from my teacher because she 60years old

  • @moa7651
    @moa7651 2 роки тому

    this is wrong
    for protiens add NaOH then Copper Sulphate and if protien is present it turns purple

    • @MissEstruchBiology
      @MissEstruchBiology  2 роки тому +1

      Hello, that's what biuret reagent is. For most UK exam boards, they require the name of the reagent rather than the chemical composition

    • @moa7651
      @moa7651 2 роки тому +1

      @@MissEstruchBiology sorry its cus i do AQA

  • @black79781
    @black79781 2 роки тому

    Can't you speak Hind mam?