Organisation of living systems

Primary EducationGrade 6ScienceCV-PRI-G06-SCI-U03-L1045–60 min
Learning LabPractise with explanations. Revise with flashcards. Review what needs more work.

You will learn

  • Connect all levels.
  • Explain interdependence.
  • Apply to a case.
  • Summarise the unit.

Version 0.2 · expanded edition · built from cited public sources Content is based on the official frameworks and sources listed under Sources and standards. No official endorsement is claimed. Written in the style of common primary school assessments. No exam result is promised.

Student lesson

The lesson in 60 seconds

  1. Levels range from cell to ecosystem.
  2. Systems depend on each other.
  3. Homeostasis keeps conditions steady.
  4. Damage at one level affects others.

Words to know

interdependence
depending on each other
homeostasis
keeping conditions steady inside the body
organism
a whole living thing
ecosystem
living things and their environment

1. Discover: The running body

Joel runs. His muscles need more oxygen, so his breathing and heart rate rise. His skin sweats to cool him. “Many systems respond together,” says his coach. “That keeps you steady.”

Think: Which systems helped Joel run?

2. Understand: Systems together

Idea 1: Levels

From cell to tissue, organ, system, organism, population, community and ecosystem: each level builds on the one below.

Idea 2: Working together

Body systems show interdependence: the lungs bring in oxygen, the heart pumps it, the muscles use it. If one fails, others suffer.

Idea 3: Steady

Homeostasis keeps body temperature, water and sugar steady using feedback from several systems.

Remember: Living systems depend on each other at every level.

3. Worked examples

Example 1 (I show you): Link

Systems.

  1. Lungs.
  2. Heart.
  3. Muscles.

Answer: They cooperate.

Example 2 (We do it together): Explain

Homeostasis.

  1. Heat.
  2. Sweat.
  3. Cool.

Answer: Keeps steady.

Example 3 (You try): Apply

Case.

Show the steps and answer
  1. Run.
  2. Rate rises.
  3. Recover.

Answer: Systems respond.

Did you know?

Your body temperature stays near 37°C although the outside temperature changes.

Why this matters

Seeing how levels connect helps us understand health and ecosystems.

4. Explore: Heart rate lab

Measure your resting pulse, then after 30 seconds of gentle marching on the spot, and record how it changes over a minute of rest.

  1. Find your pulse.
  2. Count at rest.
  3. March.
  4. Count again.
Think about it: what did you notice?

What did you notice? Pulse rose then returned to normal.

Safety first: Exercise gently for no more than 30 seconds. Stop if you feel dizzy or unwell; tell the teacher. Check allergies or conditions with an adult first. Drink water afterwards. Keep the floor clear.

5. Practise

Say it in a sentence

Use these starters when you talk about the lesson. Say them out loud.

  • ___ means depending on each other.
  • ___ keeps conditions steady.
  • An ___ is a whole living thing.
  • An ___ is living things and their environment.

Guided practice

Question 1. What is interdependence?

Depending.

Question 2. What is homeostasis?

Steady.

Question 3. What is an organism?

Whole living thing.

Independent practice

Level 1: Start

  1. What is interdependence?
  2. What is homeostasis?
  3. What is an organism?
  4. What is an ecosystem?
  5. Name two systems.

Level 2: Grow

  1. Why steady?
  2. Why pulse rises?
  3. Why cooperate?

Level 3: Stretch

  1. Run the lab.
  2. Explain.
  3. Summarise.

Answers are in the answer key below. Try first, then check.

6. Apply: Science in everyday life

Explain how systems work together when you run.

Show a sample answer

Use homeostasis.

Another one. Tell a family member one thing from this lesson. Use the words you learned.

Show a sample answer

A clear sentence that uses at least one word from Words to know.

7. Common mistakes

Mistake: “Body systems work alone.”
Fix: Together.
Another mistake: “Body temperature changes with the weather.”
Fix: Steady.

8. Lesson summary and revision card

I can…

  • I can connect all levels.
  • I can explain interdependence.
  • I can apply to a case.
  • I can summarise the unit.

9. Check and master

Answer all 14 questions. You will see feedback after each one.

1. Interdependence is … on each other

2. Homeostasis keeps conditions …

3. An ecosystem includes living things and their …

4. The heart pumps …

5. The lungs bring in …

6. Body temperature stays near …°C

7. We exercise for no more than … seconds

8. We stop if we feel …

9. We check with an … first

10. We drink … afterwards

11. The organism level comes after the …

12. A failing system affects …

Challenge 1. What happens to pulse during exercise?

Challenge 2. Why does it rise?

Your result appears here after you answer every question.

10. Key takeaways

  • Levels range from cell to ecosystem.
  • Systems depend on each other.
  • Homeostasis keeps conditions steady.
  • Damage at one level affects others.

11. Next lesson

Next lesson: Human body systems. Keep going with the next idea in this course.

Exam practice

These questions are written in the style of common school and international primary assessments. Try them on your own, without looking back. Then check your answers in the marking guide. The marks are shown in brackets.

  1. Define interdependence and homeostasis. [2 marks]
  2. Order the levels of organisation. [3 marks]
  3. Explain how systems work together during exercise. [3 marks]
  4. Safety rule. [2 marks]

Total: 10 marks.

Marking guide and model answers
  1. 1 each
  2. Cell to tissue [1]; organ to system [1]; organism to ecosystem [1]
  3. Lungs [1]; heart [1]; muscles [1]
  4. Any [1]; reason [1]

Score guide: 9 to 10 = secure. 6 to 8 = nearly there, revise the parts you missed. Under 6 = work through the lesson again with a grown-up.

Printable worksheet

  1. What is interdependence?
  2. What is homeostasis?
  3. What is an organism?
  4. What is an ecosystem?
  5. Name two systems.
  6. Why steady?
  7. Why pulse rises?
  8. Why cooperate?
  9. Run the lab.
  10. Explain.

Homework

Draw a diagram linking three body systems.

Answer key and marking scheme

Question Expected response Marks
1. What is interdependence? Depending. 1
2. What is homeostasis? Steady. 1
3. What is an organism? Whole living thing. 1
4. What is an ecosystem? Living and non-living. 1
5. Name two systems. Lungs, heart. 1
6. Why steady? Cells work best. 1
7. Why pulse rises? Muscles need oxygen. 1
8. Why cooperate? Survive. 1
9. Run the lab. Table. 1
10. Explain. Sentence. 1
Total 10

Independent practice answers. Level 1: 1 Depending.; 2 Steady.; 3 Whole living thing.; 4 Living and non-living.; 5 Lungs, heart.. Level 2: 1 Cells work best.; 2 Muscles need oxygen.; 3 Survive.. Level 3: 1 Table.; 2 Sentence.; 3 Notes..

Quiz answers: 1 B, 2 C, 3 A, 4 B, 5 C, 6 A, 7 B, 8 C, 9 A, 10 B, 11 C, 12 A, Challenge 1 B, Challenge 2 C.

Mastery and remediation

Objective Bronze (Developing) Silver (Proficient) Gold (Advanced)
O1 Connect all levels Shows this with help from an adult or a picture Does this independently and explains how they know Explains it clearly and uses it in a new situation
O2 Explain interdependence Shows this with help from an adult or a picture Does this independently and explains how they know Explains it clearly and uses it in a new situation
O3 Apply to a case Shows this with help from an adult or a picture Does this independently and explains how they know Explains it clearly and uses it in a new situation
O4 Summarise the unit Shows this with help from an adult or a picture Does this independently and explains how they know Explains it clearly and uses it in a new situation

Courseversity badge thresholds (overall quiz score): Gold = 90–100%; Silver = 80–89.9%; Bronze = 70–79.9%. A badge is never a full record of progress.

If a learner struggles

  1. Find the misconception: “Body systems work alone.” Together.
  2. Explain another way: use real objects, pictures or actions first, then words.
  3. Show a simpler example: Explain interdependence.
  4. Guided practice: work through one example together and let the learner try the next one.
  5. Reassess: use the quiz again or the worksheet.
  6. Move on when the learner shows Silver-level evidence independently.

For parents and guardians

In this lesson your child connects living systems. You do not need to be an expert to help.

  • Feel your pulse after a walk.
  • Ask “What changed?”
  • Keep it gentle.
  • Ask “how do you know?” after each answer, and listen.
  • Praise effort, not only right answers. Mistakes are how we learn.
  • Ten to fifteen minutes a day is better than one long session.

Teacher package

1–5. Objectives, prerequisites, materials, preparation, duration

Lesson objectives. Learners will: connect all levels; explain interdependence; apply to a case; summarise the unit.

Prerequisite knowledge. Grade 5 ideas: living things, plant and animal parts and using a hand lens.

Materials. Stopwatch, paper. Low-resource options: use chalk or charcoal on a board or wall, drawings in the sand, and objects from the classroom instead of printed materials.

Preparation. Clear space.

Suggested duration. 45–60 minutes. It can be split into two shorter sessions.

6–9. Teaching procedure, explanation notes, guided and independent activities

Introduction (5 min). Ask learners to run on the spot and ask, “What changed in your body?”

Explanation (10 min). Teach organisation.

Guided activity (10 min). Learners test.

Independent activity (10 min). Learners explain.

Assessment and reflection (5 min). Ask each learner to say one thing they learned and how they know it.

Key questions. Which systems work together? How is it steady?

Teacher explanation notes. Start with real objects and safe, hands-on observation. Then talk about what was seen, then draw and write. Always say “how do you know?”. Keep to the safety notes, and use local, safe materials.

10–12. Differentiation, formative assessment, common misconceptions

Support. Use real objects and pictures, short sentences and a partner. Let learners point, show or draw instead of writing. Extension. Ask learners to find a new example at home and explain how they know.

Formative assessment. Listen to learners read and explain, ask “how do you know?”, and check the independent work.

Misconceptions. “Body systems work alone.” Together.

13–15. Assessment questions, answer keys, marking scheme

Use the quiz, the 10-mark exam practice and the worksheet on this page. All answers and marking guides are in the answer sections above. Re-check every answer before use.

16–19. Remediation, enrichment, homework, teacher reflection

Remediation. Explain interdependence. Enrichment. Look for one new example near your home or school, draw it and explain it to someone. Homework. See above.

Teacher reflection. After teaching, record: which ideas learners understood; which misconceptions occurred; which activities worked; which learners need more practice; and what to improve next time.

Sources and standards

This lesson is based on the sources below, and no official endorsement is claimed. Reference starting points: Next Generation Science Standards, Cambridge Primary Science and the IB Primary Years Programme. Where a standard code is named, it points to the official framework.

Research used to shape this lesson. Courseversity Science curriculum, Grade 6 Unit 3, topic 10; Next Generation Science Standards, structure and function; Cambridge Lower Secondary Science, cells and organisation; IB Primary Years Programme, who we are. These sources informed the lesson.

Learning Lab

14 questions in 3 rounds · 4 flashcards · targeted review. Log in to save your progress.

Learning LabPractise with explanations. Revise with flashcards. Review what needs more work.
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