GCSE Biology - Structure of a Leaf and Stomata #50 

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Post-Video Quiz: 1. What do the xylem do? 2. What do the phloem do? 3. What is a waxy cuticle and what does it do? 4. How do stomata know when to open and close? 5. What are meristem cells?

THANK YOU to my teacher for sending me here. I don't like Biology normally, but I love these videos!

Funny how half the comments of people complaining about school. Really though, these are good, I learn stuff from them.

Your simple straightforward explanation really helps. Thank you :)

No because as someone with a science teacher with a freaking HEAVY SWEDISH ACCENT, this is so much easier to understand, THANK YOU🙏🙏

For anyone who needs to learn the definitions for this lesson here ya go Wilts:the plants leave and stem droop due to lack of water Turgid:rigid cells that are full of water. The vacuole pushes against the cell walls Transpiration: the flow of water through a plant Xylem:a hallow tube that carries water and minerals to its leave Stoma(plural of stomata):allows gases to exit or enter Stomata: water evaporates and escapes Flaccid:flaccid cells are floppy so they can’t hold up a plant Guard cells: each of pair of curved cells that surrounds stoma Dont worry guys I needed to write it somewhere since I memorized them soo I thought it will be useful for you Guys too 💖💖

thanking my teacher for sending me here bc they sound like tom riddle 😌 will gladly listen to this

I would ve died from stress if I didn't binge ur vids before my exam

Absolutely fantastic 👍 Quick simple and concise explanation. I admire your intro diagram of Cells ▶️ Tissue ▶️ Organs

you just summarized in 10min what it took my teacher two weeks to teach.

Epidermis- easy Palisade mesophyll- perverted men Spongy mesophyll- send many Epidermis- easy Guard cells- girls Stomata- selfies …that’s how i remember it

I appreciate this channel so much, it has saved lives I hope you read this

Was sent here by my school 😩

I swear we learnt about this in like year 7 but here we are again ig

Hey guys. I had done my Biology A Levels 6-7 years ago. and through lack of practice, I've forgotten so much of the basic information. I know it feels like a drag right now, but make sure to knuckle down and consolidate this info, and hopefully you won't forget like I did. But, you're never too old to learn! Best of luck to any of y'all going through your GCSEs!

hey yo my school sent me here ;(

For anyone that needs to learn this for a test or somein here very usefull the leaf is a plant organ tissues in leaf; | upper epidermis -- protectes the surface of the leaf Transparant allows light to pass through for potysnthesis Waxy cuticle covers this, it's an oily material reduces evaporation/ prevents the leaf from drying out | lower epidermis -- contains stomata stomata allows carbon dioxiede to enter the leaf and oxygen to leave controls the amount water vapour that can pass out the leaf on the sides of the stomata you can find gaurd cells | palisde mesophyll -- contains palise cells these are packed with chloroplast chloropast contains clorophtyll which absorbs light need for photosynthesis | Spongy mesophyll -- these have alot of airspace that allows co2 that diffuse from the stomatathrough the spongy mesopyll to get to the paslise cells Oxygen dose the opposite and comes from the palisde cells to the spngy meospyll then to the stomata ------------------------------------------------------------------------------------------------------------------------------------------------------- | Xylem -- transports water from roots to the stem and leaves. some water is then used for photosynthesis also transprts disolved mineral ions likes magnesum used to make chlorophyll | Phloem -- trasnports disolved sugars from leaves to the rest of plant the sugars are produced my photoysnynthsis sugars can be used for lika glucose used for respiration Definations Wilts:the plants leave and stem droop due to lack of water Turgid:rigid cells that are full of water. The vacuole pushes against the cell walls Transpiration: the flow of water through a plant Xylem:a hallow tube that carries water and minerals to its leave Stoma(plural of stomata):allows gases to exit or enter Stomata: water evaporates and escapes Flaccid:flaccid cells are floppy so they can’t hold up a plant

You explain very well!👍👍👍👍

thinks you are the beast teacher in the interiate , and I am undear stand .

Last bio exam tomorrow, I'm going to miss you bud.

Your videos are a life saver 🔥

Leaf: Leaves are where photosynthesis takes place, and it requires Carbon dioxide & water. The water comes from soil through the roots and xylem. List of components in the leaf: Lower epidermis: first level in which carbon dioxide diffuses. Stomata & cell guard are here. Stomata: it allows carbon dioxide to enter the leaf and oxygen to leave. Cell guard: controls when the stomata opens and when it closes. If there's a lot of water in the plant cell guards will open more and allow more carbon dioxide to enter. They close at night time when photosynthesis isn't taking place. Spongy mesophyll: a level in which carbon dioxide goes through and contains a lot of air gaps between cells so that the gas can diffuse easily into the next level. Palisade mesophyll: where photosynthesis occurs, since the palisade cells are full of chloroplasts. Upper epidermis: the last level, very transparent so that light can pass through to get to the chloroplasts in the palisade cells. Phloem: carries the sugar molecules to the rest of the plant after photosynthesis. Xylem: brings water up from the roots for the palisade cells to do photosynthesis.

Where is the link in the description?

I can’t thank you enough, I wish I could give you 1000 subs

which animation software do you use?

so if the plant was at night that means that the stomata will be closed because there ain t no sunlight to absorb and be able to photosynthesise am i right

Never knew there was so much more to leaves :O

could you explain how potassium ions cause stomata to open (if they do) ? And also, if there are other factors that could affect guard cells swelling or becoming turgid? Great video.

So helpful for studying!

Great video

I didnt listen in class when they played this video (im year 8 btw) so i wrote on my hand to watch the videos when i get home, and im so proud of myself for actually doing that!

Off topic but do u draw all the diagarams ?

yaaay Congrats on 200k!!!

Really Helpful

could you make more video's on gcse biology chemistry and physics please? i love your vids btw..the best..

Thank you! I have never seemed to understand this before but now I do

U said that guard cells are sensitive to light ,so why they didn't close at day time and instead they close at night time even though sun light come out at day time,Why?Can u explain it pls?

Thanks again for another great resource for my students to use.

bro were are yo from? thanks

One word : 🙌 LEGEND 🙌

Me watching it for THE SECOND TIME IN 3 HOURS

Why does school make us do this

guard cells with low water in the cell- im literally him

Helped in preparing for my Exam tomorrow, i thought i would fail, but instead i topped 😅.

teacher sent me here 🙃

People here from biology/science have to like this comment

I’m watching.

cool beanz :)

Imma got punished and had to lie to learn

Teacher sent me me fell asleep

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probably one of the lesser good videos cognito has made. video is just throwing stuff at me without explaining what they are

School 😵 RU-vid 🤗

Great video congrats on 1k subs

You’re talk fast😑 hard to understand what ur saying. But thanks for the video

No thanks

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