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Autotrophs vs. Heterotrophs
Autotrophs and heterotrophs represent the two main ways living things get energy. Autotrophs, like plants, can create their own food using environmental resources. Heterotrophs, like humans and animals, must consume other organisms to obtain energy.
This fundamental difference shapes entire ecosystems and food chains. Understanding these concepts helps explain how energy flows through all living systems on Earth.
How Photosynthesis Works
Photosynthesis is the amazing process plants use to make their own food. Using sunlight, chlorophyll (the green pigment in plants), and enzymes, plants transform carbon dioxide and water into glucose (sugar) and oxygen.
This chemical transformation happens in specialized structures called chloroplasts found in plant cells. The process captures solar energy and converts it into chemical energy stored in glucose molecules.
Science in Action: Every breath you take depends on photosynthesis! The oxygen you breathe is actually a byproduct of plants making their food.
The Photosynthesis Reaction
The basic photosynthesis reaction involves specific ingredients (reactants) that produce specific results (products). The reactants that go in are carbon dioxide (CO₂) and water (H₂O), while the products created are glucose (C₆H₁₂O₆) and oxygen (O₂).
For this process to work, plants need three essential components: light, chlorophyll, and enzymes. Without any of these, photosynthesis can't happen properly.
The chemical formula shows this transformation: CO₂ + H₂O → C₆H₁₂O₆ + O₂. It's worth noting that additional water is also produced as waste during this process.
The Structure of Photosynthesis
Photosynthesis happens in specific locations within plant leaves. The leaf's structure is perfectly designed for this process, with tiny openings called stomata that allow carbon dioxide in and oxygen out.
Inside the leaf, specialized cells called mesophyll cells contain chloroplasts where photosynthesis occurs. Each chloroplast has an elaborate internal structure of membranes called thylakoids, arranged in stacks called grana.
The real magic happens in these thylakoid membranes, which contain chlorophyll and other pigments that capture sunlight. The surrounding fluid (stroma) is where carbon dioxide is converted into sugar.
Did You Know? A single leaf can contain millions of chloroplasts, and each chloroplast has hundreds of thylakoids working to capture light energy!
How Plants Control Gas Exchange
Plants face a challenge: they need to let CO₂ in for photosynthesis but don't want to lose too much water. They solve this problem with guard cells that control the opening and closing of stomata (small pores on leaf surfaces).
When plants need to photosynthesize, guard cells fill with water and curve outward, creating an opening for gas exchange. When water conservation becomes more important, the guard cells lose water and close the stomata.
This opening and closing mechanism is a perfect example of homeostasis - maintaining balance despite changing conditions. Plants constantly adjust their stomata based on light, humidity, and internal water levels.
How Humans Get Energy
Unlike plants, we can't make our own food from sunlight. Instead, we get energy through cellular respiration - breaking down food molecules to release energy in the form of ATP (adenosine triphosphate).
Cellular respiration can happen with oxygen (aerobic) or without oxygen (anaerobic). The aerobic process is much more efficient and is what we primarily use for energy production.
Most of this energy conversion happens in specialized structures called mitochondria - often called the "powerhouses" of the cell. Both plant and animal cells have mitochondria with distinctive folded inner membranes called cristae where energy production occurs.
Connect the Dots: The oxygen you breathe in is used for cellular respiration, while the carbon dioxide you breathe out is used by plants for photosynthesis - it's a perfect cycle!
How Aerobic Respiration Works
Aerobic respiration is essentially the opposite of photosynthesis. The reaction takes glucose, water, and oxygen and produces carbon dioxide, water, and ATP (energy).
This complex process happens in three main stages:
- Glycolysis - glucose is split into smaller molecules called pyruvic acid in the cell's cytoplasm
- Krebs Cycle (also called citric acid cycle) - pyruvic acid is broken down into carbon dioxide in the mitochondria
- Electron Transport Chain - electrons from the Krebs Cycle help convert ADP into ATP, the usable energy currency of cells
Each stage builds on the previous one, creating a highly efficient system for extracting maximum energy from food molecules. This process powers everything you do, from thinking to running.
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Where can I download the Knowunity app?
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The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
Paul T
iOS user
Autotrophs and Heterotrophs Explained
Ever wonder how living things get energy to survive? This is all about autotrophs (organisms that make their own food) and heterotrophs (organisms that consume other organisms for food) and the processes they use to obtain energy.
Autotrophs vs. Heterotrophs
Autotrophs and heterotrophs represent the two main ways living things get energy. Autotrophs, like plants, can create their own food using environmental resources. Heterotrophs, like humans and animals, must consume other organisms to obtain energy.
This fundamental difference shapes entire ecosystems and food chains. Understanding these concepts helps explain how energy flows through all living systems on Earth.
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
How Photosynthesis Works
Photosynthesis is the amazing process plants use to make their own food. Using sunlight, chlorophyll (the green pigment in plants), and enzymes, plants transform carbon dioxide and water into glucose (sugar) and oxygen.
This chemical transformation happens in specialized structures called chloroplasts found in plant cells. The process captures solar energy and converts it into chemical energy stored in glucose molecules.
Science in Action: Every breath you take depends on photosynthesis! The oxygen you breathe is actually a byproduct of plants making their food.
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By signing up you accept Terms of Service and Privacy Policy
The Photosynthesis Reaction
The basic photosynthesis reaction involves specific ingredients (reactants) that produce specific results (products). The reactants that go in are carbon dioxide (CO₂) and water (H₂O), while the products created are glucose (C₆H₁₂O₆) and oxygen (O₂).
For this process to work, plants need three essential components: light, chlorophyll, and enzymes. Without any of these, photosynthesis can't happen properly.
The chemical formula shows this transformation: CO₂ + H₂O → C₆H₁₂O₆ + O₂. It's worth noting that additional water is also produced as waste during this process.
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The Structure of Photosynthesis
Photosynthesis happens in specific locations within plant leaves. The leaf's structure is perfectly designed for this process, with tiny openings called stomata that allow carbon dioxide in and oxygen out.
Inside the leaf, specialized cells called mesophyll cells contain chloroplasts where photosynthesis occurs. Each chloroplast has an elaborate internal structure of membranes called thylakoids, arranged in stacks called grana.
The real magic happens in these thylakoid membranes, which contain chlorophyll and other pigments that capture sunlight. The surrounding fluid (stroma) is where carbon dioxide is converted into sugar.
Did You Know? A single leaf can contain millions of chloroplasts, and each chloroplast has hundreds of thylakoids working to capture light energy!
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How Plants Control Gas Exchange
Plants face a challenge: they need to let CO₂ in for photosynthesis but don't want to lose too much water. They solve this problem with guard cells that control the opening and closing of stomata (small pores on leaf surfaces).
When plants need to photosynthesize, guard cells fill with water and curve outward, creating an opening for gas exchange. When water conservation becomes more important, the guard cells lose water and close the stomata.
This opening and closing mechanism is a perfect example of homeostasis - maintaining balance despite changing conditions. Plants constantly adjust their stomata based on light, humidity, and internal water levels.
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How Humans Get Energy
Unlike plants, we can't make our own food from sunlight. Instead, we get energy through cellular respiration - breaking down food molecules to release energy in the form of ATP (adenosine triphosphate).
Cellular respiration can happen with oxygen (aerobic) or without oxygen (anaerobic). The aerobic process is much more efficient and is what we primarily use for energy production.
Most of this energy conversion happens in specialized structures called mitochondria - often called the "powerhouses" of the cell. Both plant and animal cells have mitochondria with distinctive folded inner membranes called cristae where energy production occurs.
Connect the Dots: The oxygen you breathe in is used for cellular respiration, while the carbon dioxide you breathe out is used by plants for photosynthesis - it's a perfect cycle!
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How Aerobic Respiration Works
Aerobic respiration is essentially the opposite of photosynthesis. The reaction takes glucose, water, and oxygen and produces carbon dioxide, water, and ATP (energy).
This complex process happens in three main stages:
- Glycolysis - glucose is split into smaller molecules called pyruvic acid in the cell's cytoplasm
- Krebs Cycle (also called citric acid cycle) - pyruvic acid is broken down into carbon dioxide in the mitochondria
- Electron Transport Chain - electrons from the Krebs Cycle help convert ADP into ATP, the usable energy currency of cells
Each stage builds on the previous one, creating a highly efficient system for extracting maximum energy from food molecules. This process powers everything you do, from thinking to running.
We thought you’d never ask...
What is the Knowunity AI companion?
Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.
Where can I download the Knowunity app?
You can download the app in the Google Play Store and in the Apple App Store.
Is Knowunity really free of charge?
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
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The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
Paul T
iOS user