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Nov 30, 2025
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Exploring the Basics of Biology
Ivy
@ivy_zbah
1 / 5
Introduction to Biology: Properties of Life
Ever wonder what makes something "alive"? All living organisms share eight important properties that separate them from non-living things. The most fundamental property is that all living organisms consist of one or more cells containing genes with DNA - this is the basic building block of life!
The other seven properties include order (organized structure), regulation (maintaining internal balance called homeostasis), growth and development, energy utilization (metabolism), response to environment, reproduction (making more of their own kind), and evolution (populations changing over time).
When you see a pinecone or an animal basking in the sun, these properties are all at work! Organisms maintain their internal environment through homeostasis, like how your body keeps a constant temperature. Evolution is unique because it happens at the population level, not within individual organisms.
Did you know? Homeostasis is like your body's thermostat - it constantly adjusts to keep your internal conditions just right, no matter what's happening outside!
Life's Hierarchy of Organization
Biology gets even more interesting when we look at how life is organized in layers, from smallest to largest! This hierarchy starts at the chemical level with molecules and atoms (like DNA) and builds all the way up to the entire biosphere (all environments that support life on Earth).
The cell is the smallest level where life emerges. Cells contain specialized structures called organelles that work together. Similar cells form tissues, which combine to create organs and organ systems with specific functions. An individual living thing is an organism.
Moving outward, a group of the same species that can interbreed forms a population. Different populations living in one area make up a community. When you include both living and non-living components, you have an ecosystem. All of Earth's ecosystems together form the biosphere!
Think about it: You are simultaneously an organism made of organ systems, organs, tissues, and cells, while also being part of a population, community, ecosystem, and the biosphere!
Ecosystems and Cell Types
Ecosystems are fascinating networks where living and non-living components interact! They depend on two main processes: the cycling of nutrients (like carbon dioxide and water) and the flow of energy (starting from the sun). Every organism plays a key role in this system.
Producers like plants make their own food through photosynthesis. Consumers like humans and other animals eat other organisms for energy. Decomposers break down dead material and waste. Together, they keep energy flowing and nutrients cycling through the ecosystem.
At life's microscopic level, there are two basic cell types. Prokaryotic cells are smaller, simpler, and lack a nucleus - bacteria are the main example. Their DNA floats in a nucleoid region and they have few organelles. Eukaryotic cells (found in plants and animals) are larger and more complex with a membrane-enclosed nucleus and many specialized organelles.
Cool fact: Every time you take a step outside, you're interacting with an ecosystem that's powered by sunlight and maintained by countless organisms you can't even see!
The Three Domains of Life
Life on Earth is incredibly diverse but can be organized into three major domains. Two domains contain prokaryotes (organisms without a nucleus), while the third contains all eukaryotes (organisms with a nucleus).
Bacteria is the largest domain. These prokaryotes contain peptidoglycan in their cell walls and are found literally everywhere - in soil, water, and even inside humans! The second prokaryotic domain, Archaea, contains "ancient" microorganisms that often live in extreme conditions like hot springs or ice. Scientists believe archaea might be ancestors to eukaryotes.
The domain Eukarya contains four main kingdoms: Plantae (plants that produce sugars through photosynthesis), Fungi (decomposers like mushrooms), Animalia (animals that ingest food), and Protists (which actually contain multiple kingdoms). Most plants, fungi, and animals are multicellular (made of many cells), while protists are generally unicellular .
Fascinating! Some archaea can survive in boiling hot springs, frozen Antarctic ice, and even highly acidic environments where almost nothing else can live!
The Process of Science
Science isn't just facts to memorize - it's a powerful way of knowing based on inquiry! Scientists use two main approaches to understand the natural world: discovery science and hypothesis-driven science.
Discovery science involves making verifiable observations and measurements, like sequencing the human genome. This approach uses inductive reasoning to draw general conclusions from specific observations. For example, after examining many organisms, scientists concluded that all living things are made of cells.
Hypothesis-driven science (the scientific method) follows a formal process. It starts with a hypothesis - a proposed explanation for observations that can be tested with "if-then" predictions. This approach uses deductive reasoning, moving from general principles to specific predictions. Controlled experiments compare a control group to an experimental group where only one variable is changed at a time.
When hypotheses survive rigorous testing and explain many observations, they may become theories - widely accepted explanations supported by substantial evidence, like the theory of evolution by natural selection.
Pro tip: When designing your own science experiment, remember to change only one variable at a time and keep everything else constant. This is how you'll know what truly caused any changes you observe!
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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
Exploring the Basics of Biology
Ivy
@ivy_zbah
Biology is the scientific study of life, exploring everything from tiny cells to entire ecosystems. This fascinating subject helps us understand the 8 key properties all living things share and how life is organized at different levels. Let's dive into... Show more
Introduction to Biology: Properties of Life
Ever wonder what makes something "alive"? All living organisms share eight important properties that separate them from non-living things. The most fundamental property is that all living organisms consist of one or more cells containing genes with DNA - this is the basic building block of life!
The other seven properties include order (organized structure), regulation (maintaining internal balance called homeostasis), growth and development, energy utilization (metabolism), response to environment, reproduction (making more of their own kind), and evolution (populations changing over time).
When you see a pinecone or an animal basking in the sun, these properties are all at work! Organisms maintain their internal environment through homeostasis, like how your body keeps a constant temperature. Evolution is unique because it happens at the population level, not within individual organisms.
Did you know? Homeostasis is like your body's thermostat - it constantly adjusts to keep your internal conditions just right, no matter what's happening outside!
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Life's Hierarchy of Organization
Biology gets even more interesting when we look at how life is organized in layers, from smallest to largest! This hierarchy starts at the chemical level with molecules and atoms (like DNA) and builds all the way up to the entire biosphere (all environments that support life on Earth).
The cell is the smallest level where life emerges. Cells contain specialized structures called organelles that work together. Similar cells form tissues, which combine to create organs and organ systems with specific functions. An individual living thing is an organism.
Moving outward, a group of the same species that can interbreed forms a population. Different populations living in one area make up a community. When you include both living and non-living components, you have an ecosystem. All of Earth's ecosystems together form the biosphere!
Think about it: You are simultaneously an organism made of organ systems, organs, tissues, and cells, while also being part of a population, community, ecosystem, and the biosphere!
Sign up to see the contentIt's free!
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Ecosystems and Cell Types
Ecosystems are fascinating networks where living and non-living components interact! They depend on two main processes: the cycling of nutrients (like carbon dioxide and water) and the flow of energy (starting from the sun). Every organism plays a key role in this system.
Producers like plants make their own food through photosynthesis. Consumers like humans and other animals eat other organisms for energy. Decomposers break down dead material and waste. Together, they keep energy flowing and nutrients cycling through the ecosystem.
At life's microscopic level, there are two basic cell types. Prokaryotic cells are smaller, simpler, and lack a nucleus - bacteria are the main example. Their DNA floats in a nucleoid region and they have few organelles. Eukaryotic cells (found in plants and animals) are larger and more complex with a membrane-enclosed nucleus and many specialized organelles.
Cool fact: Every time you take a step outside, you're interacting with an ecosystem that's powered by sunlight and maintained by countless organisms you can't even see!
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Improve your grades
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By signing up you accept Terms of Service and Privacy Policy
The Three Domains of Life
Life on Earth is incredibly diverse but can be organized into three major domains. Two domains contain prokaryotes (organisms without a nucleus), while the third contains all eukaryotes (organisms with a nucleus).
Bacteria is the largest domain. These prokaryotes contain peptidoglycan in their cell walls and are found literally everywhere - in soil, water, and even inside humans! The second prokaryotic domain, Archaea, contains "ancient" microorganisms that often live in extreme conditions like hot springs or ice. Scientists believe archaea might be ancestors to eukaryotes.
The domain Eukarya contains four main kingdoms: Plantae (plants that produce sugars through photosynthesis), Fungi (decomposers like mushrooms), Animalia (animals that ingest food), and Protists (which actually contain multiple kingdoms). Most plants, fungi, and animals are multicellular (made of many cells), while protists are generally unicellular .
Fascinating! Some archaea can survive in boiling hot springs, frozen Antarctic ice, and even highly acidic environments where almost nothing else can live!
Sign up to see the contentIt's free!
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Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
The Process of Science
Science isn't just facts to memorize - it's a powerful way of knowing based on inquiry! Scientists use two main approaches to understand the natural world: discovery science and hypothesis-driven science.
Discovery science involves making verifiable observations and measurements, like sequencing the human genome. This approach uses inductive reasoning to draw general conclusions from specific observations. For example, after examining many organisms, scientists concluded that all living things are made of cells.
Hypothesis-driven science (the scientific method) follows a formal process. It starts with a hypothesis - a proposed explanation for observations that can be tested with "if-then" predictions. This approach uses deductive reasoning, moving from general principles to specific predictions. Controlled experiments compare a control group to an experimental group where only one variable is changed at a time.
When hypotheses survive rigorous testing and explain many observations, they may become theories - widely accepted explanations supported by substantial evidence, like the theory of evolution by natural selection.
Pro tip: When designing your own science experiment, remember to change only one variable at a time and keep everything else constant. This is how you'll know what truly caused any changes you observe!
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