Stages of Photosynthesis - Video Tutorials & Practice Problems

Stages of Photosynthesis

in this video, we're going to briefly introduce the stages of photosynthesis. And so photosynthesis actually occurs in two stages that we have numbered down below. And so the first stage of photosynthesis is the light reactions, and the second stage of photosynthesis is the Calvin cycle, and so moving forward in our course, we're going to talk a lot more details about both the light reactions and the Calvin cycle as well. But here in this video, we're just introducing these two stages. And so the light reactions, as their name implies, is going to convert light or photons and water into chemical, energy and oxygen gas. And the Calvin Cycle is going to use carbon dioxide from the atmosphere, as well as the chemical energy that was formed by the light reactions in order to synthesize glucose, the sugar, and so down below. In our image, we can see the stages of photosynthesis, and we know that the chloroplast acts as the site of photosynthesis and so notice that end the background here in green. What we're showing you is the chloroplast, the site of photosynthesis. But inside of the chloroplast, photosynthesis is broken up into two stages the first stage are the light reactions, which occur inside of the hill, a koi aids. And again, we'll talk a lot more about the light reactions as we move forward in our course. And then the second stage of photosynthesis are the Calvin cycle reactions, which are going to occur in the strom A of the chloroplast. And so what you can see here is when with light reactions, which is the first stage of photosynthesis, it uses light. It uses photons of light from the sun, and it also uses water. And so these two reactions come in. And what comes out our eyes oxygen, gas and chemical energy that's used to power the Calvin cycle. And so that's basically what we've described here for the light reactions now for the Calvin Cycle. Notice that it's going to use carbon dioxide from the atmosphere, along with chemical energy that was produced by the light reactions, and it's gonna use both of those to generate glucose. And so ultimately, what you can see is that coming into the chloroplast is solar energy, water and carbon dioxide, these air things that all come into the chloroplast and the things that come out of the chloroplast, our oxygen, gas and glucose. And so those are the products of photosynthesis, as we've discussed in our previous videos. And so again, we're going to talk a lot. Maura, about each of these stages of photosynthesis, the light reaction and the Calvin cycle as we move forward in our course. But for now, this here concludes our brief introduction to the two stages of photosynthesis, and I'll see you all in our next video.

Map of the Lesson on Photosynthesis

in this video, we're going to introduce our map of the lesson on photosynthesis, which is down below right here. And so notice that this map is broken up into two parts. We've got the left part over here and the right part over here. And so notice that the left part is actually going to represent you carry attic photosynthesis and the right part over here is going to represent pro carry attic photosynthesis. And so moving forward in our course were mainly and predominantly going to be focusing on photosynthesis as it occurs in eukaryotes that contain chloroplasts, organelles. And so notice on the left hand side that we're showing you a chloroplast Oregon l which we know serves as the site of photosynthesis. And and that the light reactions and the Calvin cycle reactions together make up photosynthesis. And so, moving forward in our course, will be able to talk about photosynthesis mainly in the context of how it occurs in eukaryotes inside the chloroplast. And so one thing to note is that on the inside of the chloroplast here we have the strom A to remind you that this is the chloroplast. And on the outside of the chloroplast we have the cytoplasm of the cell. So this is still inside of the cell, just outside of the chloroplast organ. L now on the right hand side over here we have pro carry attic photosynthesis. And we will talk about pro carry out photosynthesis, but in a smaller amount moving forward. But one thing to notice that is the main difference between eukaryotic photosynthesis and pro carry out photosynthesis is the location of the reactions. And so notice that the light reactions in pro carry attic organ uh organisms uh is going to be found in the plasma membrane of the cell itself, whereas the light reactions uh and eukaryotic organisms occurs in the file. Opioids within the chloroplast also noticed that the Calvin cycle uh and pro Kerasiotes occurs in the cytoplasm, whereas the Calvin cycle and eukaryotes occurs in the shroh MMA of the chloroplast. And so the location is going to be different. And this is once again because pro Kerasiotes do not contain uh these chloroplasts organelles. And so once again, we'll get to talk a lot more about photosynthesis and these reactions as we move forward, we will mainly be focusing on eukaryotic photosynthesis, but we will get to talk a little bit about pro carry attic photosynthesis as well. So, I'll see you all in our next video

Based on the map above, how does photosynthesis differ in eukaryotes and prokaryotes?

• A. The order of the 2 stages is different.
• B. In prokaryotes, the product of the Calvin cycle is lactose.
• C. The location of the 2 stages is different.
• D. There is no difference in photosynthesis between the two cell types.