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Maryahna Schleich
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Biology
Animals chapter 1 notes
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Animal Basics
Everything starts with cells! Animals are made of tiny building blocks called cells that work together. When cells join forces, they create more complex structures.
You'll discover how animals are organized from the smallest parts to complete organisms. Animals have special features called adaptations that help them survive in their environments.
Fun Fact: Did you know that your body contains trillions of cells that all work together to keep you alive?
From Cells to Organisms
Cells are the basic units of structure and function in all living things. They're like tiny factories that keep animals alive.
When similar cells work together, they form tissues. These tissues combine to create organs like your heart or brain. Multiple organs working together form organ systems like your digestive system. Finally, all these systems together make up a complete organism - a living thing!
Animals have special adaptations that help them get food and oxygen, maintain stable internal conditions, move around, and reproduce.
Remember This: The organization levels go from smallest to largest: cells → tissues → organs → organ systems → organism.
What Makes an Animal?
Animals belong to their own kingdom and have some special features. All animals are multicellular, meaning they have many specialized cells working together.
Animals also are eukaryotic, which means their cells have a nucleus. Two other important animal traits are that they can move and they're consumers (they eat food rather than make their own like plants do).
Each animal has slightly different genetic information, creating variation even within the same species. This genetic variation makes each animal unique!
Think About It: How are you different from your classmates or siblings? Some of these differences come from genetic variation!
Vertebrates vs. Invertebrates
When you think of your favorite animal, you probably picture a vertebrate - an animal with a skull and backbone. These include fish, amphibians, reptiles, birds, and mammals.
Surprisingly, vertebrates make up less than 5% of all animal species! The other 95% are invertebrates - animals without backbones. These include insects, jellyfish, snails, and worms.
Beetles alone have about 290,000 different species! Moths and butterflies have 112,000 species, and ants, bees, and wasps have 103,000 species.
Wow Fact: For every vertebrate animal you can name, there are about 19 invertebrate species that exist!
Animal Symmetry
Symmetry refers to the balanced arrangement of body parts. Most animals have some form of symmetry, which helps them move and function.
There are three main types of symmetry in animals. Bilateral symmetry means an animal can be divided along one line to create mirror-image halves (like humans). Radial symmetry means an animal has many lines of symmetry (like a starfish). Some animals are asymmetrical, meaning they have no specific symmetry (like some sponges).
The type of symmetry an animal has often relates to how it moves and lives in its environment.
Try This: Look in a mirror and draw an imaginary line down the middle of your face. Notice how both sides are similar but not exactly the same!
Simple Invertebrates: Sponges & Cnidarians
Sponges (Porifera) are very simple invertebrates that filter food from water. They have pores all over their bodies and an opening called an osculum at the top.
Cnidarians include jellyfish, coral, and sea anemones. These animals have tentacles with stinging cells to catch prey. They have an incomplete digestive system, which means they have only one opening that serves as both mouth and anus.
Jellyfish have an interesting life cycle! They start as attached polyps and then develop into free-swimming medusas as adults.
Cool Fact: Despite having no brain, jellyfish can still hunt effectively using their stinging tentacles!
Worm World
There are three main types of worms, each with different body structures. Flatworms (Platyhelminthes) are simple worms with incomplete digestive systems. Examples include planarians, flukes, and tapeworms.
Roundworms (Nematodes) have round, long, slender bodies. Common types include pinworms and hookworms that can sometimes infect people and pets.
Segmented worms (Annelida) are the most complex worms. They have bodies divided into segments and complete digestive systems. Earthworms, bristle worms, and leeches belong to this group.
Did You Know? Having a complete digestive system (with separate mouth and anus) makes eating more efficient - animals can take in food and eliminate waste at the same time!
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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
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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
Comprehensive Notes on Animals: Chapter 1
Let's dive into the fascinating world of animals! Animals are living organisms with special characteristics that make them different from plants and other living things. This chapter explores the basic building blocks of animals, their types, and some interesting invertebrates... Show more
Animal Basics
Everything starts with cells! Animals are made of tiny building blocks called cells that work together. When cells join forces, they create more complex structures.
You'll discover how animals are organized from the smallest parts to complete organisms. Animals have special features called adaptations that help them survive in their environments.
Fun Fact: Did you know that your body contains trillions of cells that all work together to keep you alive?
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From Cells to Organisms
Cells are the basic units of structure and function in all living things. They're like tiny factories that keep animals alive.
When similar cells work together, they form tissues. These tissues combine to create organs like your heart or brain. Multiple organs working together form organ systems like your digestive system. Finally, all these systems together make up a complete organism - a living thing!
Animals have special adaptations that help them get food and oxygen, maintain stable internal conditions, move around, and reproduce.
Remember This: The organization levels go from smallest to largest: cells → tissues → organs → organ systems → organism.
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What Makes an Animal?
Animals belong to their own kingdom and have some special features. All animals are multicellular, meaning they have many specialized cells working together.
Animals also are eukaryotic, which means their cells have a nucleus. Two other important animal traits are that they can move and they're consumers (they eat food rather than make their own like plants do).
Each animal has slightly different genetic information, creating variation even within the same species. This genetic variation makes each animal unique!
Think About It: How are you different from your classmates or siblings? Some of these differences come from genetic variation!
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Vertebrates vs. Invertebrates
When you think of your favorite animal, you probably picture a vertebrate - an animal with a skull and backbone. These include fish, amphibians, reptiles, birds, and mammals.
Surprisingly, vertebrates make up less than 5% of all animal species! The other 95% are invertebrates - animals without backbones. These include insects, jellyfish, snails, and worms.
Beetles alone have about 290,000 different species! Moths and butterflies have 112,000 species, and ants, bees, and wasps have 103,000 species.
Wow Fact: For every vertebrate animal you can name, there are about 19 invertebrate species that exist!
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Animal Symmetry
Symmetry refers to the balanced arrangement of body parts. Most animals have some form of symmetry, which helps them move and function.
There are three main types of symmetry in animals. Bilateral symmetry means an animal can be divided along one line to create mirror-image halves (like humans). Radial symmetry means an animal has many lines of symmetry (like a starfish). Some animals are asymmetrical, meaning they have no specific symmetry (like some sponges).
The type of symmetry an animal has often relates to how it moves and lives in its environment.
Try This: Look in a mirror and draw an imaginary line down the middle of your face. Notice how both sides are similar but not exactly the same!
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Simple Invertebrates: Sponges & Cnidarians
Sponges (Porifera) are very simple invertebrates that filter food from water. They have pores all over their bodies and an opening called an osculum at the top.
Cnidarians include jellyfish, coral, and sea anemones. These animals have tentacles with stinging cells to catch prey. They have an incomplete digestive system, which means they have only one opening that serves as both mouth and anus.
Jellyfish have an interesting life cycle! They start as attached polyps and then develop into free-swimming medusas as adults.
Cool Fact: Despite having no brain, jellyfish can still hunt effectively using their stinging tentacles!
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Worm World
There are three main types of worms, each with different body structures. Flatworms (Platyhelminthes) are simple worms with incomplete digestive systems. Examples include planarians, flukes, and tapeworms.
Roundworms (Nematodes) have round, long, slender bodies. Common types include pinworms and hookworms that can sometimes infect people and pets.
Segmented worms (Annelida) are the most complex worms. They have bodies divided into segments and complete digestive systems. Earthworms, bristle worms, and leeches belong to this group.
Did You Know? Having a complete digestive system (with separate mouth and anus) makes eating more efficient - animals can take in food and eliminate waste at the same time!
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Sign up to see the contentIt's free!
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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