---
title: "The Human Skeleton"
description: "Describe the structure and four main functions of the human skeleton: support, protection, movement, and production of blood cells in bone marrow"
canonical: https://lightmysky.com/learn/science/the-human-skeleton-mt_Qkl46lyris
source: https://lightmysky.com/learn/science/the-human-skeleton-mt_Qkl46lyris.md
retrieved: 2026-10-19
---

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# The Human Skeleton

Describe the structure and four main functions of the human skeleton: support, protection, movement, and production of blood cells in bone marrow

Subject: Science · Area: Organisms & Life Processes · Ages 11 to 13
Page: https://lightmysky.com/learn/science/the-human-skeleton-mt_Qkl46lyris

## Ready when they can

- Lists and explains the four functions of the skeleton with examples
- Names key bones and identifies which organs they protect (e.g. ribcage protects heart and lungs)
- Explains what bone marrow is and where blood cells are made

## Lesson: What Your Skeleton Really Does

You already know that bones and muscles work together so you can move. But movement is only one job your skeleton does. It also supports your body, protects your organs, and makes new blood cells inside your bones.

*(drawing: Your skeleton does four big jobs at once. It holds you up, it protects your organs, it helps you move, and it makes blood cells.)*

**Example.** Your ribcage curves around your chest like a cage, and that shape is exactly its job. It protects your heart and lungs from bumps and falls. Your skull protects your brain, and your spine protects the spinal cord, the bundle of nerves running down your back.

Bone marrow is the soft tissue inside your bones, especially in long bones like your femur, or thigh bone, and in flatter bones like your hip bones. Marrow is not empty space. It is where your body makes new red blood cells, which carry oxygen, and white blood cells, which fight germs.

**Tip.** A simple way to remember: your skeleton is a scaffold that holds you up, a shield that protects your organs, a set of levers for movement, and a factory that makes blood cells.

**Recap.** The skeleton supports your body, protects key organs like the brain, heart, and lungs, works with muscles to move you, and makes blood cells in its marrow.

## Practice

8 questions on this page, each with its working shown.

## Needs first

- [Cells to organ systems](https://lightmysky.com/learn/science/cells-to-organ-systems-mt_7hB8s5eOP1)
- [Skeletons & Muscles](https://lightmysky.com/learn/science/skeletons-and-muscles-mt_g4YSiOCS8g)

## Opens up

- [Joints, Tendons & Ligaments](https://lightmysky.com/learn/science/joints-tendons-and-ligaments-mt_yefw2CQT4x)