---
title: "Joints, Tendons & Ligaments"
description: "Explain biomechanics — the interaction between skeleton and muscles at joints, including the roles of tendons (attach muscle to bone) and ligaments (attach bone to bone)"
canonical: https://lightmysky.com/learn/science/joints-tendons-and-ligaments-mt_yefw2CQT4x
source: https://lightmysky.com/learn/science/joints-tendons-and-ligaments-mt_yefw2CQT4x.md
retrieved: 2026-10-19
---

> **Agent view.** This is the Markdown twin of the page, for tools and assistants.
> When to use this site, and the call that answers each job: https://lightmysky.com/agent-instructions.md
> API description (OpenAPI 3.1): https://lightmysky.com/openapi.json · Authentication: https://lightmysky.com/auth.md
> Pricing: https://lightmysky.com/pricing.md · Catalog: https://lightmysky.com/llms.txt · Full catalog: https://lightmysky.com/llms-full.txt
> Every machine-readable file on this domain: https://lightmysky.com/.well-known/ai-catalog.json
> Ask for Markdown with `Accept: text/markdown`, a `.md` address, or `?mode=agent`.

# Joints, Tendons & Ligaments

Explain biomechanics — the interaction between skeleton and muscles at joints, including the roles of tendons (attach muscle to bone) and ligaments (attach bone to bone)

Subject: Science · Area: Organisms & Life Processes · Ages 11 to 13
Page: https://lightmysky.com/learn/science/joints-tendons-and-ligaments-mt_yefw2CQT4x

## Ready when they can

- Distinguishes between tendons and ligaments and gives the function of each
- Describes how a synovial joint works (e.g. the knee or elbow)
- Explains how force is transmitted from muscle through tendon to bone to produce movement

## Lesson: Tendons, Ligaments, and Moving Joints

Your skeleton gives shape and holds you up, but bones cannot move alone. Kicking a ball needs muscles, tendons, and ligaments, each with its own job.

A tendon connects a muscle to a bone. When the muscle contracts and gets shorter, it pulls the tendon, and the tendon pulls the bone. That pull is what makes the bone move.

A ligament connects one bone to another bone. It does not pull anything. Its job is to hold the two bones together at a joint and stop them from slipping too far out of place.

**Example.** Look at your knee. Your thigh bone and shin bone meet there, and ligaments cross between them to hold the joint steady. A slippery fluid inside the joint lets the bones glide instead of grinding. When your thigh muscle contracts, it pulls a tendon, the tendon pulls your shin bone, and your knee straightens.

*(drawing: Every movement follows the same chain: the muscle contracts, the tendon carries the pull, and the bone moves. Ligaments just hold the joint steady while it happens.)*

**Tip.** Tendon starts like 'to,' as in muscle to bone. Ligament links bone to bone. If it pulls, it is a tendon. If it just holds, it is a ligament.

**Recap.** Tendons pull bones to create movement. Ligaments hold bones together at the joint.

## Practice

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

## Needs first

- [The Human Skeleton](https://lightmysky.com/learn/science/the-human-skeleton-mt_Qkl46lyris)

## Opens up

- [Bone, Cartilage and the Mechanics of a Joint](https://lightmysky.com/learn/science/bone-cartilage-and-the-mechanics-of-a-joint-mt_1_q3aL7E5D)
- [Muscles Work in Pairs](https://lightmysky.com/learn/science/muscles-work-in-pairs-mt_lm0usBAF53)