Digestive, Circulatory, and Lymphatic Systems

Grade 12 · Biology

Semester 1 | Period 3 | Week 14

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Subject: Biology

Semester: 1

Period: 3

Week: 14


School Name:
Teacher’s Name:
Subject: Biology
Grade Level: Grade 12
Date: Week 14
Lesson Duration: 45 minutes
Week & Period: Week 14, Period III
Topic: Digestive, Circulatory and Lymphatic Systems
Sub-topic: Circulatory System – Heart, Blood Vessels, Blood Components

 

Learning Objectives

By the end of the lesson, learners will be able to:

  1. Explain the structure and function of the human heart.
  2. Identify types of blood vessels and their roles.
  3. Describe the composition of blood and its functions.
  4. Distinguish between pulmonary and systemic circulation.

 

Previous Knowledge

Learners have learned about digestion and the need for nutrients to be transported to body cells.

 

Instructional Materials

  • Model or chart of the human circulatory system
  • Diagrams of heart and blood vessels
  • Video of heartbeat animation
  • Flashcards showing blood components

 

Lesson Development – ABC Model

🅰️ A – Anticipation (Warm-up / Starter)

Time: 5–10 minutes
Begin by asking:

  • “What do you think moves nutrients and oxygen around your body?”
  • “Why do your veins appear blue but blood is red?”

Allow learners to briefly feel their pulse or heartbeat.

 

B – Building Knowledge (Main Lesson Body)

Time: 25–30 minutes

  1. Heart
  • Muscular organ that pumps blood throughout the body.
  • Has four chambers: right and left atria (upper), right and left ventricles (lower).
  • Heartbeat is controlled by electrical impulses.
  1. Blood Vessels
  • Arteries: Carry blood away from the heart (usually oxygenated).
  • Veins: Return blood to the heart (usually deoxygenated).
  • Capillaries: Tiny vessels where exchange of gases and nutrients takes place.
  1. Types of Circulation
  • Pulmonary circulation: Blood flows from heart to lungs and back.
  • Systemic circulation: Blood flows from heart to rest of the body and returns.
  1. Blood Composition
  • Red Blood Cells (RBCs): Carry oxygen.
  • White Blood Cells (WBCs): Fight infections.
  • Platelets: Help with clotting.
  • Plasma: Liquid part that carries hormones, nutrients, waste.

 

Learners’ Activities (Expanded)

  • Label a heart diagram showing four chambers
  • Match vessels to their functions (artery, vein, capillary)
  • View a simple animated video of the heartbeat and blood flow
  • Group activity: trace blood flow from the body to heart, to lungs, and back

🅲️ C – Consolidation (Conclusion & Assessment)

Time: 5–10 minutes
Ask:

  • “What happens if the heart stops working?”
  • “Which blood vessel carries blood from the heart to the lungs?”
  • “What are the functions of red and white blood cells?”

 

Evaluation Methods

  • Multiple choice questions on circulatory parts
  • Labelling exercise on blood vessels
  • Oral explanation of systemic vs pulmonary circulation
  • Blood composition matching game

 

Short Notes (Expanded)

  • The heart is the main pump in the circulatory system. It has valves to prevent backflow of blood.
  • Arteries carry blood away from the heart; veins bring it back.
  • Blood consists of plasma, RBCs, WBCs, and platelets.
  • Circulation is pulmonary (lungs) and systemic (body).
  • The pulse is the heartbeat felt in arteries as blood is pumped.

 

Extra Instructions for Expanded Work

Expanded Notes:

  • Provide a diagram of heart with flow arrows
  • Explain why the left ventricle has a thicker wall
  • Include notes on heart valves and their importance

Assignment:

  1. Label a heart diagram.
  2. List and explain 3 blood vessels.
  3. Draw a simple diagram showing pulmonary vs systemic circulation.

Optional Extension:

  • Use a simple stethoscope or app to listen to a heartbeat
  • Write a short paragraph: “Why blood is important to life”

 

Differentiation / Inclusive Strategies

  • Use color-coded models to explain chambers and vessels
  • Give extra time and support for learners with visual impairments using tactile diagrams
  • Allow oral or group responses for those with writing difficulties

 

Teacher Reflection

  • Did learners understand the structure and function of the heart?
  • Could learners differentiate the vessels and circulations?
  • Were learners able to describe blood components accurately?