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Katie mento
12/1/2025
AP Biology
Overview of the Skeletal System: Bones, Cartilage, and Bone Marrow
138
•
Dec 1, 2025
•
Katie mento
@katiemento_ptvi
The skeletal system forms the body's essential framework, providing structure,... Show more
Your skeleton is more than just a rigid frame—it's a living, dynamic system. Bone tissue (osseous tissue) forms the dense connective structure that makes up most of your adult skeleton, protecting soft tissues and providing attachment points for muscles through tendons.
Bones serve multiple critical functions beyond support. They store calcium, house bone marrow for blood cell production, and protect vital organs. Inside your bones, two types of marrow exist: yellow marrow (containing fat cells that store energy) and red marrow (where hematopoiesis, or blood cell production, occurs).
Cartilage complements the skeletal system as a semi-rigid connective tissue that provides flexibility and smooth surfaces for joint movement, like in your ribcage and joints.
Did you know? Before puberty, children have more red marrow in their bones, which is why they can produce blood cells more rapidly than adults. As you age, yellow marrow (fat storage) gradually replaces some red marrow.
Your bones are alive with cellular activity! The process begins with osteoprogenitor cells—young cells that can divide and develop into bone-forming cells called osteoblasts. These osteoblasts then mature into osteocytes, the most common bone cell type, which maintain the mineral balance in your bone matrix.
When your body needs calcium, specialized cells called osteoclasts (a type of white blood cell) break down bone tissue to release it. This calcium is essential for multiple body functions including blood clotting, muscle contraction, and transmitting nerve signals.
Hematopoiesis happens in the red marrow where special stem cells called hemocytoplasts can develop into any blood cell your body needs. A kidney hormone called erythropoietin specifically stimulates the production of red blood cells.
Remember this: Your bones aren't just static structures—they're dynamic tissues constantly being built up by osteoblasts and broken down by osteoclasts in a balanced process that keeps your skeleton healthy.
Bone cells perform specialized jobs that keep your skeletal system functioning properly. Osteoblasts actively form new bone, working primarily in growing regions including the periosteum (outer bone layer) and endosteum (inner surface). As they create and calcify bone matrix, they become trapped within it.
Once trapped, osteoblasts transform into osteocytes—the primary cells of mature bone. Located in small cavities called lacunae, these cells maintain the mineral concentration in bone matrix and secrete important enzymes. Though less active than osteoblasts, osteocytes are crucial for bone health.
Osteogenic cells are the only bone cells that can divide, making them vital for growth and repair. Found in the deep periosteum and bone marrow, they replenish the supply of bone-forming cells. Meanwhile, osteoclasts continually break down old bone, working alongside osteoblasts in a constant remodeling process.
Think about it: Your entire skeleton regenerates approximately every 10 years through this continuous cycle of bone formation and breakdown—you literally aren't made of the same bones you had a decade ago!
Bone gets its strength from a unique combination of materials. The bone matrix consists of approximately 60% minerals (primarily calcium and phosphorus in the form of hydroxyapatites) and 40% organic materials (primarily collagen, or osteoid). This combination provides both strength and slight flexibility.
Your skeleton features two main bone tissue types. Compact bone forms the dense outer layer of bones, particularly in the shafts (diaphyses) of long bones, providing strength and protection. Spongy bone (also called cancellous bone) has a honeycomb-like structure with spikes called trabeculae, typically found at the ends of long bones.
Woven bone appears in developing skeletons and during healing. It contains less mineral content than mature bone and is normally replaced by stronger bone types as you develop—finding it in adults usually indicates a healing injury.
Fascinating fact: Pound for pound, your bones are stronger than reinforced concrete, yet they're light enough to support movement. This remarkable combination comes from their matrix composition and internal structure.
Long bones are longer than they are wide and function as levers when muscles contract. Examples include the humerus, radius, and ulna in your arms; the femur, tibia, and fibula in your legs; and the metacarpals and phalanges in your fingers and toes. These bones enable most of your body's movement.
Short bones are cube-shaped with roughly equal dimensions in length, width, and thickness. Found in your wrists (carpals) and ankles (tarsals), they provide stability and support while allowing limited motion in these complex joints.
Spongy bone forms the interior of most bones, particularly at the ends of long bones (epiphyses). This lightweight structure contains osteocytes housed in small cavities called lacunae, with a lattice-like network of bony spikes called trabeculae that provide strength while minimizing weight.
Pro tip: When studying bone types, relate them to their functions—long bones create movement, short bones enable precision, flat bones protect organs, and irregular bones handle complex attachments. This functional approach makes identification much easier!
Flat bones have a thin, curved shape and include your cranial bones, shoulder blades (scapulae), sternum, and ribs. They primarily protect internal organs and provide large surfaces for muscle attachment, making them crucial for both protection and movement.
Irregular bones have complex shapes that don't fit other categories. Your vertebrae, facial bones (including sinuses), sphenoid, and ethmoid bones fall into this category. These specialized structures protect organs while accommodating unique anatomical needs.
Two less common bone types include sutural bones (small bones that develop within skull sutures, also called wormian bones) and sesamoid bones like your kneecaps (patellae). Sesamoid bones develop within tendons and help them overcome compression forces, protecting them during movement.
Remember this: Bone growth occurs in two ways: longitudinal growth (increasing length) and appositional growth (increasing width). Understanding these growth patterns helps explain why bones can get wider throughout life but stop growing longer after puberty.
Bone development (osteogenesis) begins about 8 weeks after fertilization through two distinct processes. Endochondral ossification forms most of your skeleton, including long bones. In this process, mesenchymal tissue first forms hyaline cartilage models, which are gradually replaced as chondrocytes transform into osteocytes.
Intramembranous ossification creates flat bones like your skull. This direct process doesn't require a cartilage model—instead, mesenchymal cells develop into dense fibrous connective tissue, where osteoblasts form bone directly. This process creates the familiar "soft spots" (fontanels) in a baby's skull.
Both processes involve osteoblasts secreting an enzyme called alkaline phosphatase, which helps add calcium to forming bone. The primary ossification center appears first, followed by secondary centers, with growth continuing from these points.
Interesting fact: During fetal development, your entire skeleton starts as soft tissue before transforming into the hard structure you know. This remarkable transformation process continues after birth, with some bones not fully ossifying until your early 20s!
Ossification follows a specific sequence that transforms soft tissue into hard bone. First, a primary ossification center forms in the center and sides of developing bone as the surrounding perichondrium transforms into periosteum (the bone's outer membrane).
Next, the inside of the developing bone hollows out to form the marrow cavity. Specialized osteoclasts remove bone material from the center, creating space for the marrow that will produce blood cells and store fat.
Secondary ossification centers then form in the epiphyses (ends of long bones), creating spongy bone in these regions. This is why the ends of your bones have a different internal structure than the shafts.
Visualization tip: Think of bone development like building a house—first the frame goes up (primary ossification), then the interior spaces are hollowed out (marrow cavity formation), and finally the specialized rooms are finished (secondary ossification). This mental image helps you remember the sequence!
The epiphyseal plate (growth plate) is the key area where bones grow longer. This layer of hyaline cartilage between the diaphysis and epiphysis is where ossification actively occurs in developing bones. At the end of puberty, these plates convert to epiphyseal lines, stopping further length growth.
Hormones precisely control this growth process. The anterior pituitary gland produces growth hormone that prompts your liver to secrete substances called somatomedins, which stimulate cartilage growth in the epiphyseal plates. The thyroid gland produces thyroxine that stimulates osteoblasts to convert cartilage into bone.
During puberty, sex hormones play a crucial role in bone development. Testosterone in males and estrogen in females stimulate a growth spurt, but ultimately cause the epiphyseal plates to close, ending height increase.
Clinical connection: Understanding the role of growth plates explains why growth-related treatments must occur before puberty ends. Once epiphyseal plates convert to epiphyseal lines, bone lengthening therapies become ineffective.
Your skeleton serves as your body's calcium bank, storing and releasing this vital mineral as needed. Two key hormones control this process: calcitonin from the thyroid gland stimulates osteoblasts to remove excess calcium from blood and deposit it in bones, while parathormone from the parathyroid glands activates osteoclasts to break down bone and release calcium into the bloodstream.
This delicate balance of calcium levels affects numerous body functions including muscle contraction, nerve signal transmission, and blood clotting. When calcium levels drop too low, parathormone triggers bone breakdown to restore balance; when levels rise too high, calcitonin promotes bone deposition.
Bone remodeling continually reshapes your skeleton throughout life. Matrix is resorbed on one bone surface while being deposited on another, allowing bones to respond to changing physical demands. This process explains why weight-bearing exercise strengthens bones while inactivity weakens them.
Application insight: Weight-bearing exercises like walking, running, and resistance training stimulate bone remodeling in response to mechanical stress, increasing bone density and strength. This is why exercise is so important for preventing osteoporosis!
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.
You can download the app in the Google Play Store and in the Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
App Store
Google Play
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
Katie mento
@katiemento_ptvi
The skeletal system forms the body's essential framework, providing structure, protection, and a site for blood cell production. Beyond just supporting your body, bones store vital minerals, enable movement, and undergo continuous remodeling throughout your life. Understanding how this dynamic... Show more
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Your skeleton is more than just a rigid frame—it's a living, dynamic system. Bone tissue (osseous tissue) forms the dense connective structure that makes up most of your adult skeleton, protecting soft tissues and providing attachment points for muscles through tendons.
Bones serve multiple critical functions beyond support. They store calcium, house bone marrow for blood cell production, and protect vital organs. Inside your bones, two types of marrow exist: yellow marrow (containing fat cells that store energy) and red marrow (where hematopoiesis, or blood cell production, occurs).
Cartilage complements the skeletal system as a semi-rigid connective tissue that provides flexibility and smooth surfaces for joint movement, like in your ribcage and joints.
Did you know? Before puberty, children have more red marrow in their bones, which is why they can produce blood cells more rapidly than adults. As you age, yellow marrow (fat storage) gradually replaces some red marrow.
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Improve your grades
Join milions of students
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Your bones are alive with cellular activity! The process begins with osteoprogenitor cells—young cells that can divide and develop into bone-forming cells called osteoblasts. These osteoblasts then mature into osteocytes, the most common bone cell type, which maintain the mineral balance in your bone matrix.
When your body needs calcium, specialized cells called osteoclasts (a type of white blood cell) break down bone tissue to release it. This calcium is essential for multiple body functions including blood clotting, muscle contraction, and transmitting nerve signals.
Hematopoiesis happens in the red marrow where special stem cells called hemocytoplasts can develop into any blood cell your body needs. A kidney hormone called erythropoietin specifically stimulates the production of red blood cells.
Remember this: Your bones aren't just static structures—they're dynamic tissues constantly being built up by osteoblasts and broken down by osteoclasts in a balanced process that keeps your skeleton healthy.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Bone cells perform specialized jobs that keep your skeletal system functioning properly. Osteoblasts actively form new bone, working primarily in growing regions including the periosteum (outer bone layer) and endosteum (inner surface). As they create and calcify bone matrix, they become trapped within it.
Once trapped, osteoblasts transform into osteocytes—the primary cells of mature bone. Located in small cavities called lacunae, these cells maintain the mineral concentration in bone matrix and secrete important enzymes. Though less active than osteoblasts, osteocytes are crucial for bone health.
Osteogenic cells are the only bone cells that can divide, making them vital for growth and repair. Found in the deep periosteum and bone marrow, they replenish the supply of bone-forming cells. Meanwhile, osteoclasts continually break down old bone, working alongside osteoblasts in a constant remodeling process.
Think about it: Your entire skeleton regenerates approximately every 10 years through this continuous cycle of bone formation and breakdown—you literally aren't made of the same bones you had a decade ago!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Bone gets its strength from a unique combination of materials. The bone matrix consists of approximately 60% minerals (primarily calcium and phosphorus in the form of hydroxyapatites) and 40% organic materials (primarily collagen, or osteoid). This combination provides both strength and slight flexibility.
Your skeleton features two main bone tissue types. Compact bone forms the dense outer layer of bones, particularly in the shafts (diaphyses) of long bones, providing strength and protection. Spongy bone (also called cancellous bone) has a honeycomb-like structure with spikes called trabeculae, typically found at the ends of long bones.
Woven bone appears in developing skeletons and during healing. It contains less mineral content than mature bone and is normally replaced by stronger bone types as you develop—finding it in adults usually indicates a healing injury.
Fascinating fact: Pound for pound, your bones are stronger than reinforced concrete, yet they're light enough to support movement. This remarkable combination comes from their matrix composition and internal structure.
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Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Long bones are longer than they are wide and function as levers when muscles contract. Examples include the humerus, radius, and ulna in your arms; the femur, tibia, and fibula in your legs; and the metacarpals and phalanges in your fingers and toes. These bones enable most of your body's movement.
Short bones are cube-shaped with roughly equal dimensions in length, width, and thickness. Found in your wrists (carpals) and ankles (tarsals), they provide stability and support while allowing limited motion in these complex joints.
Spongy bone forms the interior of most bones, particularly at the ends of long bones (epiphyses). This lightweight structure contains osteocytes housed in small cavities called lacunae, with a lattice-like network of bony spikes called trabeculae that provide strength while minimizing weight.
Pro tip: When studying bone types, relate them to their functions—long bones create movement, short bones enable precision, flat bones protect organs, and irregular bones handle complex attachments. This functional approach makes identification much easier!
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Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Flat bones have a thin, curved shape and include your cranial bones, shoulder blades (scapulae), sternum, and ribs. They primarily protect internal organs and provide large surfaces for muscle attachment, making them crucial for both protection and movement.
Irregular bones have complex shapes that don't fit other categories. Your vertebrae, facial bones (including sinuses), sphenoid, and ethmoid bones fall into this category. These specialized structures protect organs while accommodating unique anatomical needs.
Two less common bone types include sutural bones (small bones that develop within skull sutures, also called wormian bones) and sesamoid bones like your kneecaps (patellae). Sesamoid bones develop within tendons and help them overcome compression forces, protecting them during movement.
Remember this: Bone growth occurs in two ways: longitudinal growth (increasing length) and appositional growth (increasing width). Understanding these growth patterns helps explain why bones can get wider throughout life but stop growing longer after puberty.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Bone development (osteogenesis) begins about 8 weeks after fertilization through two distinct processes. Endochondral ossification forms most of your skeleton, including long bones. In this process, mesenchymal tissue first forms hyaline cartilage models, which are gradually replaced as chondrocytes transform into osteocytes.
Intramembranous ossification creates flat bones like your skull. This direct process doesn't require a cartilage model—instead, mesenchymal cells develop into dense fibrous connective tissue, where osteoblasts form bone directly. This process creates the familiar "soft spots" (fontanels) in a baby's skull.
Both processes involve osteoblasts secreting an enzyme called alkaline phosphatase, which helps add calcium to forming bone. The primary ossification center appears first, followed by secondary centers, with growth continuing from these points.
Interesting fact: During fetal development, your entire skeleton starts as soft tissue before transforming into the hard structure you know. This remarkable transformation process continues after birth, with some bones not fully ossifying until your early 20s!
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Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Ossification follows a specific sequence that transforms soft tissue into hard bone. First, a primary ossification center forms in the center and sides of developing bone as the surrounding perichondrium transforms into periosteum (the bone's outer membrane).
Next, the inside of the developing bone hollows out to form the marrow cavity. Specialized osteoclasts remove bone material from the center, creating space for the marrow that will produce blood cells and store fat.
Secondary ossification centers then form in the epiphyses (ends of long bones), creating spongy bone in these regions. This is why the ends of your bones have a different internal structure than the shafts.
Visualization tip: Think of bone development like building a house—first the frame goes up (primary ossification), then the interior spaces are hollowed out (marrow cavity formation), and finally the specialized rooms are finished (secondary ossification). This mental image helps you remember the sequence!
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Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
The epiphyseal plate (growth plate) is the key area where bones grow longer. This layer of hyaline cartilage between the diaphysis and epiphysis is where ossification actively occurs in developing bones. At the end of puberty, these plates convert to epiphyseal lines, stopping further length growth.
Hormones precisely control this growth process. The anterior pituitary gland produces growth hormone that prompts your liver to secrete substances called somatomedins, which stimulate cartilage growth in the epiphyseal plates. The thyroid gland produces thyroxine that stimulates osteoblasts to convert cartilage into bone.
During puberty, sex hormones play a crucial role in bone development. Testosterone in males and estrogen in females stimulate a growth spurt, but ultimately cause the epiphyseal plates to close, ending height increase.
Clinical connection: Understanding the role of growth plates explains why growth-related treatments must occur before puberty ends. Once epiphyseal plates convert to epiphyseal lines, bone lengthening therapies become ineffective.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Your skeleton serves as your body's calcium bank, storing and releasing this vital mineral as needed. Two key hormones control this process: calcitonin from the thyroid gland stimulates osteoblasts to remove excess calcium from blood and deposit it in bones, while parathormone from the parathyroid glands activates osteoclasts to break down bone and release calcium into the bloodstream.
This delicate balance of calcium levels affects numerous body functions including muscle contraction, nerve signal transmission, and blood clotting. When calcium levels drop too low, parathormone triggers bone breakdown to restore balance; when levels rise too high, calcitonin promotes bone deposition.
Bone remodeling continually reshapes your skeleton throughout life. Matrix is resorbed on one bone surface while being deposited on another, allowing bones to respond to changing physical demands. This process explains why weight-bearing exercise strengthens bones while inactivity weakens them.
Application insight: Weight-bearing exercises like walking, running, and resistance training stimulate bone remodeling in response to mechanical stress, increasing bone density and strength. This is why exercise is so important for preventing osteoporosis!
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.
You can download the app in the Google Play Store and in the Apple App Store.
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
Health
Algebra
Calculus 1
Algebra 1
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