Superb

tbh at some point it give a look he is using ai face, can u relate?

I am cooked

push pull gravitational upthurst air resistance contact and noncontact forces with explanation amd diagram I seared this and found ur amazing video…❤❤

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Accomodation: A reflex which changes the reflective power of the lense. Both the cornea and the lense refract or bend light whilst the ciliary muscles and suspensory ligaments control the shape of the light. When light hits the eye it somehow has to be focus perfectly onto the retina (onto the part called the fovea), to do this, the light must be refracted (change direction). This is mainly achieved by the cornea which always refracts light by the same amount, meanwhile the role of the lense is to fine tune the refraction so that the light rays always converge exactly on the fovea (regardless of whether the object is close or far away). In order for the eye to refract light enough (especially for close objects), the lense is short and fat so that it is more curved, allowing it to refract more strongly. When looking at a nearby object, the ciliary muscles contract inwards towards the lense. Because it is closer to the lense, the suspensory ligaments slacken (this means they become loose). Because they are no longer pulling the tight on the lense, the lense is free to return to its usual fatter shape, so it can now refract light more strongly. For distant objects, the light doesn't need to be refracted as strongly, so the lense doesn't need to do as much as the cornea has almost fully refracted the light enough. In order to reduce the refractive power of the lense, it needs to be stretched out, so that its surface is less curved. In order to achieve this, the ciliary muscles relaxes, moving away from the lense and pulling the suspensory ligaments taut, this stretches the lense out. A key thing to remember is that the ciliary muscles contract they are moving inwards towards the lense rather than outwards. The suspensory ligaments aren't muscles so can't contract or relax. They can only be pulled taut or slacken. Whereas the ciliary muscles can contract or relax. When the lense can't refract enough, it leads to people being long sighted as the image is formed behind the retina making it blurry. This means that they can focus on far objects but not nearby objects. To fix this, we wear glasses which contain convex lenses which help by providing extra refracting power so that the eye is then able to focus the light onto the retina properly. When the lense refracts to much, it leads to people becoming short sighted. Light from distant objects which doesn't need to be refracted very much ends up being over refracted, this means that it focuses and forms an image before the retina. This means that the light rays don't focus properly on the retina and the objects appear all blurry. To fix this, we wear glasses containing concave lenses. This causes the light to refract outwards, counteracting the over refraction, allowing the light to focus on the retina properly. The medical name for long sighted people is hyperopia. The medical name for short sightedness is myopia.

As light hits the eye, the first structure that it meets is the cornea. To allow light to pass through, the cornea is completely transparent, and so has no blood vessels. This means that all of the oxygen that it needs has to diffuse into it from the outside air rather than being supplied by the blood, unlike all other parts of the body. The reason we need the cornea is because it causes all the light that passes through it to refract (bend by a certain amount). The next important structue is the iris which is the coloured bit of the eye. It controls how big or small the pupil is. The pupil itself is not actually a structure, rather a gap in the middle of the iris which allows the light to pass through to the lense. Just like the cornea, the job of the lense is to refract or bend light, but importantly the lense can change its shape - this allows it to control how strongly it refracts the light. This helps it always focus the light perfectly onto the retina at the back of the eye. The retina itself is made up of two different types of receptor cells - cone cells which are sensitive to the colour of light (allowing us to see colour but don't work very well in low light conditions) and rod cells which are more sensitive to light but only allow you to see black and white. This is why you can't see colours in the dark as it is only your rod cells that are working. The next structure to know is the fovea which is a special spot on the retina which is filled with only cone cells and it is this region which we try to focus light on so that we can see things most clearly. Lastly, we have the optic nerve. This takes all the impulses generated by the receptor cells and transmits them to the brain. When in an extremely bright environment, the intensity of the light can cause damage to the retina, so to prevent this, you have a reflex that controls the size of your pupil, making it smaller in bright light environments so that less light can enter and damage your retina. The pupil is referred to as constricted. This becomes larger in lower light conditions as it lets more light in. helping you see in the dark. The pupil is referred to as dilated. To control this, the iris is made up of two different types of muscles. On the inside are circular muscles which stretch around the pupil in circles. Around the outside are radial muscles which stretch from the inside to the outside like the radius of a circle. In order to make the pupil smaller in bright light, the circular muscles contract, squeezing the pupil smaller and the radial muscles are relaxed so that they can be stretched longer. If it is dark, the circular muscles relax and the radial muscles contract to mark it shorter and to pull the pupil open, letting in more light.

Awesome

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John 14:8 - If God is all you have, you have all you need. Psalm 46:1 - God is our refuge and strength, a very present help in trouble. Romans 8:18 - The Pain You've Been Feeling Can't Compare To The Joy That's Coming. Exodus 14:14 - The Lord Will Fight For You , You Just Need To Be Still. Jesus loves you all✝️💟 May God guide you throughout your whole entire life and lead you to the right path of life‼️‼️

Summary of all you need to know: The thermoregulatory centre which is a part of the hypothalamus inside our brain acts as a thermostat for our body. To help it, we also have receptors throughout our body which are tiny things that detect a change in body temperature. Most of them are found in the skin and our blood vessels. By constantly sending information about our temperature to the thermoregulatory centre, the brain is able to figure out whether we are too hot or cold overall. If we are too hot, it will send us signals designed to cool us back down. If we are too cold it will bring about changes that warm us back up. In order to warm us up, we need to conserve the heat that we have and generate more. To conserve our heat, we constrict the blood vessels that lie near the surface of our skin (known as vasoconstriction). This means that less blood flows near the surface and less heat energy is lost to our surroundings. We also contract erector muscles which makes our hairs stand on end (this traps a small layer of insulating air, meaning its harder to lose heat from our skin - helps to keep us warm). To generate more body heat, we also shiver, where our muscles contract automatically, this requires a lot of energy from respiration. The chemical reactions involved result in a lot of heat energy released as moist which ends up warming us up. To cool us down, we do the opposite. The erector muscles relax allowing the hairs to fall flat. The blood vessels expand (vasodilate) allowing more heat energy to be transferred to our surroundings as lots of warm blood is passing close to the skins surface. We also produce sweat which is a mixture of water and salt that we release onto the surface of our skin. As the sweat evaporates, it takes heat energy from our body away with it as it requires a lot of energy to evaporate water - leaving us cooler.

doing this the night before my exam 😭😭😭

bio yr11 mocks tmrw 💔

Why is there a spike in FSH in the middle? I don't understand what it's for and there is high oestrogen at that point which I thought would inhibit it?

thank you so much !! i have my november mock exam for bio tomorrow and my teacher explains complex things like the kidneys so poorly. i can finally understand XD !

I am so cooked. I have my mocks tmrw but I just can't understand 😢. Even after watching Cognito, I think I am a lost cause

thxشكرا

I'm so grateful for your videos, like i was doing a question that i did not understand one bit but i watched your video and i did it right. i have test tomorrow and i was panicking about this but luckily I watched your video.

im so confused why this is on my topic lists for a non calculator test 😭😭

😮

Wait aaaaaahhhhh brooo man I have exams tomorrow:(

Here i am in yr 8 studying this while i am told you also need this in GCSE quadratic formular is wayy harder and i understood it yall are really dummies

can you slove this y=x^2+2 and y= x+14

Thank you very very much. It saved a lot of time and I learnt it in five minutes, and my concept got clear

love you, sir. You saved my exams!! 🙏🙏

😁😁tysmm

I notice that you didn't state the estimated number of fungi species as you did for plants and animals. Why?

saving me 2 weeks prior mcat is insane

Please anyone explain what is mean by double science and triple science 🙏🏻

If I get A* in physics, it's undoubtfully because of you, Thank you so much🤗

Hey

Awesome.

If I get A* in physics, it's undoubtfully because of you, Thank you so much🤗

thank you!

4:12 this was really useful and especially since I have a test in 9 mins

Bro this is for grade 6 people doing this for college 💀

i have physics test in two hours....

If I get A* in math, it's undoubtfully because of you, Thank you so much🤗

Hi but how does the ionic compound structure differ from another ionic bond which is not a compond

If i get A* in math, it's undoubtfully because of you, Thank you so much🤗

Excellent ❤

This guy is gonna save my grades

You are a bloody lifesaver, best of wishes and luck towards you lot

this channel taught me more than my teachers

lol me before mocks be like

I woulda failed my test if not for this video. I liked and subscriebd