so for this video we are going to be looking at the factors that affect diffusion rate we will be seeing what are the factors that will increase the rate of diffusion or decrease the weight of diffusion now the first most obvious factor that will affect diffusion rate is temperature temperature is the easiest thing to explain for example so in this case here we are going to show you two situations so in one particular situation on the left it's in 5 degree celsius and on the right side it is 30 degree celsius and in both cases the particles will move from left to right because it's a higher concentration to lower concentration but in which case will diffusion happen faster the answer is obviously the second diagram okay at 30 degree celsius because when there is a higher temperature the particles will gain a higher kinetic energy and when it gains a higher kinetic energy it is then able to diffuse at a faster rate simple as that the second one that we are going to be looking at is something called concentration gradient now what is the meaning of concentration gradient concentration gradient basically means the difference in concentration between two areas now I'm going to divide it again to situation A and situation B in a what happens is on the left side there are six particles and on the right side there are two particles in B the left side has 12 particles and the right side has two particles and I've put down the numbers there for you so you can see that as a reference now in both A and B the particles will still move from left to right why because diffusion is from higher to lower concentration but in which case will diffusion happen at a higher rate to do this you will have to compare the difference in concentration in both A and B so in a if we were to draw out a triangle to represent 6 as the higher number and two as the lower number and in B when I would if I were to draw out the triangle and in this case the difference is 12 and 2 so the triangle looks a bit more different and when you compare the gradient a has a less steep concentration gradient and B has a steeper concentration gradient and the steeper the concentration gradient it will actually cause a higher diffusion rate the reason is because in B the particles will collide more frequently causing it to occupy an emptier space so how can we apply concentration gradient to daily lives okay I'll give you one example I don't need you to memorize this yet but this is more relevant in chapter nine you see what actually happens is in our lungs there is a particular tissue known as the alveoli and the function of the alveoli in our lungs is to allow gas exchange for example when there is oxygen in the alveoli what needs to happen normally is it needs to diffuse into the blood as I've represented over here as you can see in situation A here there is a higher concentration of oxygen in the alveolus compared to the capillary and diffusion will happen but if I want more oxygen to diffuse into the capillary at a higher diffusion rate what I need to do is I need to breathe in more air and when I breathe in more air what will happen here is there will be a higher concentration of oxygen in the alveoli thus when you compare the concentration gradient in B what will actually happen is it has a steeper concentration gradient compared to a therefore there will be a higher diffusion weight of oxygen into the blood your blood receives more oxygen and it gets transported to the whole body that is how concentration gradient is relevant we will also see why concentration gradient is relevant when we are studying chapter 7 plant transport and More in particular when we are looking at transpiration so look out for that now the Third factor that will also affect diffusion rate is something known as surface area in my situation over here you have two animal cells the annual cell on the left let's imagine those red colored dots as particles the red colored dots will be able to enter the animal cell by crossing the cell surface membrane but imagine the animal cell on the right it wants to increase the amount of particles it can take in by diffusion okay if it wants to increase the amount of particles it can take in by diffusion what can happen is the cell surface membrane can fold and form something known as microvilli which we have seen in chapter one and the function of the microvilli is to just increase the surface area of the cell surface membrane and thus by doing so it the particles actually have more space to enter the cell or it has more surface area or more room to enter the cell as I have represented in the arrows so the size of the cell technically did not increase between the two of them when you think about it but because of the microvilli more particles can enter the Cell at any given time compared to the one on the left so surface area is also something quite important as well