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13. Photosynthesis

Leaf & Chloroplast Anatomy


Leaf & Chloroplast Anatomy

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in this video, we're going to talk a little bit about leaf and chloroplast anatomy, and we're going to start off by defining the mess. A Phil and so the Messa Phil is referring to the interior leaf tissue consisting of of, of course, lots of messa Phil cells. And so these messy feel cells air characterized by having ah, lot of chloroplasts organelles and recall that the chloroplast serve as the site of photosynthesis. And so because these messy Phil cells have a lot of chloroplasts and these messy Phil cells make up the mess Ifill tissue, this means that the mess a field tissue of belief, is responsible for performing photosynthesis for the plant. And so, within the word missile fill, you can see these routes. Mess owes a route that means metal, and Phil is a route that means leaf. And so, if you put them together, Messa Phil, it's really just referring to the middle leaf or the interior leaf tissue. And if we take a look at our image down below, over here on the left hand side, notice that we're showing you a leaf that you might be able to walk outside and seeing a tree or find on the ground somewhere. And so if you zoom into this leaf, you'll notice that it's going to have tissue that has messa Phil tissue consisting of messa Phil cells. And so notice that these messy feel cells are found right here in this interior middle region here of the leaf. And so each of these Messa Phil cells which you can see uh, side by side by side here, each of them contain lots of chloroplasts and the chloroplasts are these tiny little green circles that you see within each of these missile fuel cells. And you can see that if we were to zoom into one of these chloroplast, the chloroplast would look like this. And so what's important to note is that the leaf also have these very important structures that are referred to as Sto Mata and the Sto Mata are not to be confused with the Strom A, which is a region within the chloroplast itself. The stone mata are different than the Strom A and so you don't want to confuse those two terms. So what in the world are these Tamada that we're referring Thio? Well, the Samata are tiny little holes or pores that are in the leaf itself and these tiny little holes or pores and leaf. They can actually open and they can close, and what they do is they control gas exchange between the leaf and the environment. And so these still Mata are responsible for allowing the gas exchange of carbon dioxide, gas, oxygen, gas and even water as water vapor, which are all components of photosynthesis. And so, really, the stone mata being in an open position, it will allow for the gas exchange and allow for photosynthesis to proceed as normal. And so later in our course, when we talk about different types of photosynthesis, comparing C three, C four and Cam photosynthesis will be able to talk a lot. Maura about thes still mata. But for now, you should just know that the stone mata are tiny holes in the leaf that allow for gas exchange with the atmosphere. Now, in addition to this, we need to recall the anatomy of the chloroplast itself, which recall are the organelles that act as the site of photo synthesis. This is where photosynthesis is going to take place. Within each self is within the chloroplast and the chloroplast themselves have very, very important anatomy which we can also review here in this image, down below on the right. So first off, notice that the still mata you can actually visualize Here is these little openings that you can see here within the leaf itself. And so this is referring to the still Mata and so you can see that the stone mata is really just this opening here. And through this opening, this can allow for gas exchange. It can allow for carbon dioxide to diffuse and and it can also allow for oxygen gas that's produced a diffuse out. And it could even allow for water to diffuse out or in as water vapor. And so this opening here, this Tamada is gonna be very, very important for again allowing for gas exchange. And when it is open, it will allow for gas exchange. But when it's closed, it will not allow for gas exchange. And we'll talk about what happens when it's closed again later in our course, in a different video, when we're talking about different types of photosynthesis but for now again, within each of these missile fuel cells there are a bunch of chloroplasts and if we zoom in tow one of the chloroplasts, you will see that it looks like this and chloroplasts also have very important anatomy to refresh our memories on. So recall that chloroplasts have two membranes. They have an outer membrane that surrounds the entire organ. L But then they also have an inner membrane, and the inner membrane is embedded within here and then within the inner membrane, which you'll notice is that there are these stacks of green looking pancakes here. And these green looking pancakes are not actually pancakes. They're actually called Fila Coy aids. Okay, so inside of the chloroplast are these structures that look like green pancakes. But they're actually called Fila Coy's, and each individual green pancake is called Ethel a Coid. However, the stacks of green pancakes have a different term. So if you're referring to an entire stack of Fila coy IDs, then that stack is referred to as a grain, um or grana for plural. And so, just outside of the Fila coins, but still within the chloroplast, this region within the chloroplast but just outside of the Thill accords is referred to as the Strom A and the Strom A once again sounds kind of similar to the sto mata, but they're referring to very different things. The stone Maada once again are referring to the openings or the holes or pores that air in the leaf that allow for gas exchange. The Strom A is within a tiny little chloroplast that we're zooming in here on. It's just this fluid filled space here within the chloroplast, so it's important to keep in mind. Now, once again, the chloroplast are the site of photosynthesis, and ultimately what we're going to see is that photosynthesis is going to be powered. The power for photosynthesis is going to come by absorbing what are known as electro magnetic wavelengths of light. And so we'll be able to talk more about these electromagnetic waves of light as we move forward in our course. But for now, you should note that electromagnetic waves of light are gonna provide the power to drive photosynthesis and chloroplasts are able to obtain that power by absorbing these electromagnetic waves of light. And so this year concludes our brief introduction to leaf in chloroplast anatomy, defining the missile Fill the stem Ottawa and reviewing chloroplast anatomy. And as we move forward in our course, will continue to talk Mawr and Maura about photosynthesis, so I'll see you all in our next video.

A gelatinous matrix inside the chloroplast containing ribosomes, DNA and enzymes is the:

a) Granum.

b) Chlorophyll.

c) Thylakoid.

d) Stroma.

e) Mitochondria.


Which plant structure is responsible for a plant’s gas exchange with the atmosphere?

a) Chloroplast.

b) Stomata.

c) Mesophyll.

d) Stroma.