Testing a leaf for starch for IGCSE Biology

This is a step by step demonstration of how to test a leaf for starch. Each step is explained. I'm using a variegated geranium leaf which has cholophyll only in some areas. The end screen summarises the method. I hope it helps!
Suitable for all exam boards.
Thanks to Alby for his help.

[@allsosavvy]

0:47 was probably the cleanest match strike I've ever seen

[@TomDare]

It's a source of considerable pride.

[@sillykatttt]

I agree

[@malachi__]

same here. not bad video but i would have never seen it otherwise.

[@nadaalzubaidy7477]

@@malachi__ i think youre replying to the wrong comment bro but same

[@hjka-ux5nr]

10/10

[@whelvetooth1435]

Who else was forced to watch this for school.....

[@williamgrant9334]

me

[@TomDare]

Man, life is tough. Feel for you guys...

[@instinctshadow4950]

Me

[@ellaconnelly5886]

AHAHAHHAHAHAH ME

[@leafytiger2447]

me

[@juliekovatcheva522]

Thank you SOO much , I can see the passion you have when educating students. We need more teachers like you!:)

[@TomDare]

Thanks!

[@jaanarodrigo4880]

yess! he seems like he really want kids to enjoy bio

[@johanyeah3189]

where do i get a Variagated leaf?

[@gayboi9776]

A weed farm

[@fatimanauman868]

For anyone unable to see the last slide properly
- Draw the leaf showing areas with and without chlorophyll
- put in boiling water for 30 seconds
- Turn off Bunsen
- Boil in ethanol using a water bath
- put back in water for 30s
- spread out on white tile and lightly drizzle with iodine solution
- draw the leaf indicating areas with and without starch
(picture and picture helps to see it too, if this is pretty obvious then pretend this comment is non-existent ig :D)

[@yousefazab8141]

thanks man
ALOT

[@dimebagdarrell2390]

3:20 he has the same expressions as a Mii on wii sports when you throw the bowling ball backwards

[@TomDare]

Proper old school reference. Respect.

[@roxers8700]

who else is here from their bio lesson

[@glitchgamer610]

yes

[@amelia3jay]

me:)

[@MYSTmke]

Yup

[@katiepatton2195]

Me

[@pakalaka_j]

Yh

[@slofy_]

Anyone else Watching this as home learning

[@katiepatton2195]

Me

[@savagegaming427]

yep

[@pengovilapucho5707]

Me my teacher said so

[@densetsu5078]

Me

[@yogurllay7462]

Yep

[@lizxyplays5331]

i read this topic 4 times and i would keep forgetting the information but then i had the thought to look up the experiment to see with my own eyes and im glad i thought of that and found ur wonderful video thank u.

[@hala-ov4de]

YOOOO POG THIS MADE ME GET A FULL MARK

[@johanyeah3189]

where do i get a Variagated leaf?

[@hala-ov4de]

johan yeah what wtf is that

[@waterbottlecompany]

@@johanyeah3189 a variegated leaf is basically a leaf that is green and white. you can get it a plant store ig idk.

[@sheabo0012]

THIS WAS VERY POGCHAMP TOM THANK YOU SIR I AM NOW A GENIUS

[@johanyeah3189]

where do i get a Variagated leaf?

[@nanakirima]

@@johanyeah3189 any leaf that has variations in its color

[@lovinsum]

WOOOOOO POGGERS WERE ALL SMART NOW!

[@sumayakhumalo6678]

@@johanyeah3189 me too

[@prongyao]

Thank you so much for sharing the starch test. In our country, schools do not have any laboratory, and we are studying science subjects like walking in the dark. Your video helps me a lot with my study Mr., Thanks again.

[@TomDare]

So glad to help. Which country are you watching from?

[@prongyao]

@@TomDare From Myanmar, Sir

[@tobyfogg5861]

we students dont get paid for our job lol

[@robynshepherdd7865]

ikr, we need to get paid..

[@MNR_CFC]

bruh we need to pay for something we dont want

[@kaykay2768]

n it sucks😂

[@KindFiction]

Anyone else's teacher tell them to watch this during online school/biology??

[@0308.]

Love from Pakistan dude,I am Cambridge IGCSE student from Pakistan and ur videos helped me for my ATP prepration.

[@TomDare]

And back at you from the UK! Hope all the study pays off!

[@user-sd9is9si6o]

How sad doing science at a level

[@reis_6167]

Tysm, this changed my life completely

[@nickcrampton4914]

POV: you were forced to watch this for your biology lesson but you ended up just reading the comments...

[@tommyyiannakou9250]

ratio

[@tommyyiannakou9250]

w

[@tommyyiannakou9250]

w

[@amal.i38]

Amazing, the colours came out so well! Thank you so much, will definitely be showing this video to my class😊

[@manamendradasantha1177]

Actually this test was more understandable ,and thanks sir

[@sumayakhumalo6678]

Thank you Sir this was helpful, so what are the safety precautions when doing this because I want to try it out?

[@LivingstonKalule-je6no]

Thank u sir I have learnt this by the tym our tr taught this I was absent so I was just cramming from friends thanks alot

[@prometheus_78]

0:47 that match strike tho

[@shadowjuniors839]

Ppl who like this comment are here bc of school....

[@GG4EVA623]

1:10 the trump gesture tho 😂🤣

[@TomDare]

I hadn't seen that before. It totally is. Wow.

[@molten7391]

lmao

[@_rainbow_vibes_4310]

I agree 🤣🤣😂😂

[@johanyeah3189]

where do i get a Variagated leaf?

[@henrique7pg926]

who has to watch this video in lockdown

[@TomDare]

Is the answer 'Henrique Pereira Guerrero'?

[@shwushintay352]

Me

[@livvyallan2474]

Meeeeeee

[@ildepheponsengendahimana1978]

thank you that help a lot 😍😍😍😍😍

[@sunnahwear7540]

Awesome video dude, keep up the great work 😉😀

[@mrbolsita1470]

here I am, watching this video after two years it has been published haha. Greetings from argentina :)

[@iloveeveryone47]

tysmmmmmmm ur explaination was much better than those words in my text book 😁😊

[@TomDare]

Glad it has been helpful!

[@OG_Shady]

I don't know if you Will reply,But Thank You my teacher sent me here this was good:)
Actually my teacher didn't send me it's for my exam:)

[@ridhamkabra889]

I am in summer vacation this is still fun to watch

[@TomDare]

Kudos to you!

[@AW-ty8ol]

This helped me a lot in my online studies, thanks

[@TomDare]

Glad to be helping!

[@johanyeah3189]

where do i get a Variagated leaf?

[@eieiphyo499]

As I'm Grade11 student, I have to learn about it in my biology textbook and it's really useful and helpful for me.
Thank u so much, teacher!❣️

[@TomDare]

So glad it helped!

[@JanellMeyer]

I have tried this experiment multiple times with variegated pothos leaves --many different varieties-- but have yet to be successful. I was hoping to write up a lab for my advanced students to do, but if I can't do it I can't hope that they will be successful.

[@SiyabongaMkhwanazi1]

Why do we test for starch in the leaf not for sugar?

[@DTren1]

Who else here to study for biology?

[@saeedamohamed4245]

Thank you sir this helped me for my project in bio

[@rizikikondokelwa-um5up]

Why is it necessary to get rid of chlorophyll

[@Itxmaaz806]

Very gooood🎉

[@ComedyPetHD]

Can you please respond I have a question.Why is the leaf boiled in the water?

[@Akuetteh-AkotoBRIANDT]

Can you do an experiment on how flowers absorb water

[@rizriz6477]

My science teacher made me watch this ⊙︿⊙

[@Camelman-zn4oi]

This was very helpful thank you

[@hostthegamevibeile8978]

Whats that white ip that forms on plants by nature from starch

[@sirbuzzer7320]

thanks so much this helped me with my test : )

[@hostthegamevibeile8978]

Like the pop rock candy sound and its the reason it pops in nature

[@evieharrisonboo]

im here for the into/outro LALALAL LA LAAAAAA

[@MandisaLira-b3t]

Can you please give all three variable and identify each one

[@jamal6935]

Thank you for educating me
#wap
#emo is fun

[@kyliechaneditzzz]

If we remove chlorophyll why is there still starch present?

[@Limefilms]

i was hold on gunpoint to watch this video

[@jeromekenfack6601]

It is very good like an 😂😂😮😮😮😊experiment

[@kyliechaneditzzz]

I don't get it if ethanol removes chlorophyll why does the leaf turn blue black

[@Dyiing]

Iodine forms a blue/black complex with starch, which is left in the leaf, not chlorophyll

[@o_hall7h981]

who's watching in 2021

[@shwushintay352]

Me

[@rynisme9350]

This man is a genius. who thought anyone would use a science equipment to hold a camera XD.

[@bihansathathsari7254]

anyone watching this at 2021in school or home .........

[@ki6ran]

watching this in lockdown, because we cant do the practical

[@ahmadafaneh1954]

actually,the noiling water is used for the braking of cell membranes

[@diyeah1036]

Amazing video I could understand every thing

[@TomDare]

Really glad it helped!

[@oliverfletcher6707]

Most thought through tea ever

[@lpsangel3]

Great video!

[@TomDare]

Glad you enjoyed it

[@niamh4201]

GO KING

[@sibongilenancy3352]

What is the aim of this practical activity

[@SarfrazSvar]

Well said; it is EVIDENCE and not PROOF that glucose is required to make starch and photosynthesis is needed. Science is empirical.

[@kbroad749]

Why was alcohol used to treat the leaf?

[@TomDare]

This removes the chlorophyll, turning the leaf white so that the a colour change is easier to see during the iodine test.

[@williamisaac-barker5877]

Can sm1 tell me the observations from the experiment

[@xeniaaa]

thankyouuuuuuuuuu dr.tom!!!!

[@sahasra_loveyourself_]

Nice video was helpful

[@TomDare]

Glad it helped

[@takutski5851]

Who else is watching this for science?

[@bluediamond3688]

Really good video

[@TomDare]

Thanks Blitzy

[@sheabo0012]

YOU ARE GOOD AT FARMING LULW AND TWITCH PRIMES

[@johanyeah3189]

where do i get a Variagated leaf?

[@hibakouzi4544]

so u kill a leaf just to see if it has starch ???

[@francissaute3808]

Very helpful

[@TomDare]

Glad you think so!

[@StonerBoy-mel0dy]

This helped a lot thanks bro

[@TomDare]

Pleasure - glad it helped

[@francissaute3808]

Great vid

[@joraa]

is bedatine okay to be an alternative to use for iodine?

[@kenjaboo8057]

I'm not sure but it might

[@ayshahassimsakoor1008]

What colour would the leaf turn if starch was not present in the leaf🤔

[@GachaNet-vs2yl]

orange maybe

[@supersarah8796]

Orange

[@R-OHAN]

10YAC triple?

[@incognito9537]

Love you Mr Dare😍❤💘

[@johanyeah3189]

where do i get a Variagated leaf?

[@tomclarke6901]

From a weed farm

[@curry1331]

im doing homework at 11pm while watching this

[@jamso6926]

Not my proudest baby making time

[@johanyeah3189]

where do i get a Variagated leaf?

[@nedtyson2230]

Any one in my science class seeing this?

[@edwardnashtonsglasses]

idk y i need this for year 8 science revision

[@rizriz6477]

Anyone here in March?

[@hostthegamevibeile8978]

It evaporates in wilderness a op to rain etc

[@JP-ml3cs]

hmmm @Aryan Suryawanshi

[@jamso6926]

Wow very inspirational

[@AngelineZhang-l1p]

Whose school ask for a conclusion

[@SilasHarveyRobothamMawdsley]

Love the music

[@palmerfn1094]

this helped with my school work.

[@TomDare]

Glad it helped!

[@lintheteacher]

What I really liked is the bgm in the beginning and the end😂😂

[@evilmil1099]

Anyone else watching this for fun 😂

[@tengwermiriam4293]

Hello prof, do you have starch extraction protocol , I'm working on physiochemical parameters of water chestnut

[@niamh4201]

WOOOOOOOO

[@Venusrival]

who is here because of covid-19?

[@elizabethgreenhalgh3031]

i love the outro music

[@johanyeah3189]

where do i get a Variagated leaf?

[@nickcrampton4914]

3:29 minecraft xp noises

[@anonymouslonely7765]

you liked your own comment and you play minecraft. Respect -73769483686482686868654.7734218945624528

[@ThebiggestCraig]

I can't unhear that now.

[@hostthegamevibeile8978]

But pops sometimes a bo effect

[@TreverBettis]

Do wild plants have starch Tom? I thought only man made hybrid plants have it.

[@TomDare]

All plants have starch!

[@learnwithswayamwagh4523]

i watched from India

[@TomDare]

Great! Hope this video is helpful!