Pathogens and Parasites, Meaning, Differences and Examples for SS 3

Class: SS 3
Term: First Term
Week: 10
Age: 14 years
Duration: 45 minutes
Subject: Health Education
Curriculum Theme: to causation.
Previous Lesson: Disability and Rehabilitation
Topic: PATHOGENS AND PARASITES
Subject Matter: Define pathogens and parasites with examples(e.g. bacteria, fungi, ricketsia, helminthes, worms): Differences between pathogens and parasites and Characteristics of each non- communicable disease in relation

Specific Objectives

By the end of the lesson, pupils/students should be able to:

Cognitive Domain

• Define pathogens and parasites.
• List examples of pathogens, such as bacteria, fungi, and rickettsia.
• List examples of parasites, such as helminthes and worms.
• State the differences between pathogens and parasites.
• Identify characteristics of non-communicable diseases.

Affective Domain

• Appreciate the importance of understanding disease-causing agents.
• Develop an interest in preventive health practices.

Psychomotor Domain

• Tabulate the differences between pathogens and parasites.
• Illustrate examples of pathogens and parasites.

Reference Materials

The following resources were used in planning this lesson:

• 2014 9 Years Basic Education Curriculum
• Relevant State Unified Scheme of Work
• A suitable textbook
• FCT ERC/NAPPS Scheme of work

Instructional Materials

The teacher will teach this lesson with the aid of:

• Charts showing different types of pathogens (e.g., bacteria, fungi)
• Charts showing different types of parasites (e.g., tapeworm, roundworm)
• Pictures illustrating diseases caused by pathogens and parasites
• Whiteboard and markers

Rationale for the Lesson

This lesson is important for students to understand the biological agents that cause diseases and their modes of action. Distinguishing between pathogens and parasites helps in comprehending disease transmission and developing effective prevention strategies. This knowledge is fundamental for promoting personal and community health.

Prerequisite/Previous Knowledge

Students should have a basic understanding of health, disease, and some common illnesses from their previous Health Education classes.

Lesson Content/Board Summary

PATHOGENS AND PARASITES

Meaning of Pathogens

Pathogens are microorganisms or agents that can cause disease in a host. They are typically microscopic and include various types of germs that invade the body and disrupt its normal functions.

Examples of pathogens include:

1. Bacteria: Single-celled microorganisms that can cause diseases like tuberculosis, cholera, and typhoid fever.
2. Fungi: Organisms like yeasts and moulds that can cause skin infections (e.g., ringworm) and respiratory diseases.
3. Rickettsia: A type of bacteria that lives inside other cells and causes diseases such as typhus and Rocky Mountain spotted fever.

Meaning of Parasites

Parasites are organisms that live on or in a host organism and obtain nutrients at the host’s expense, often causing harm. They depend on the host for survival and reproduction.

Examples of parasites include:

1. Helminthes: These are parasitic worms, such as tapeworms, roundworms (Ascaris), and hookworms, which can infest the intestines and other organs.
2. Worms: A general term for various invertebrate animals, many of which are parasitic, including the helminthes mentioned above.

Differences Between Pathogens and Parasites

The key differences between pathogens and parasites are:

1. Size: Pathogens are generally microscopic (e.g., bacteria, viruses), while parasites can be microscopic (e.g., protozoa) or macroscopic (e.g., worms, ticks).
2. Relationship with Host: Pathogens cause disease by direct infection and multiplication within the host, often leading to rapid illness. Parasites live on or in the host, deriving nutrients and often causing chronic conditions or weakening the host over time.
3. Nature: Pathogens are primarily agents of disease (e.g., bacteria, viruses, fungi). Parasites are organisms that have a parasitic lifestyle, meaning they depend on a host for survival.
4. Examples: Pathogens include bacteria, viruses, fungi, and rickettsia. Parasites include protozoa, helminthes (worms), and arthropods (e.g., lice, ticks).

Characteristics of Non-Communicable Diseases

Non-communicable diseases (NCDs), also known as chronic diseases, are medical conditions or diseases that are non-infectious and non-transmissible among people. They are typically of long duration and result from a combination of genetic, physiological, environmental, and behavioural factors.

Characteristics of NCDs include:

1. They are not caused by infectious agents (pathogens).
2. They are not transmitted from person to person.
3. They often have a long duration and slow progression.
4. They are often associated with lifestyle factors (e.g., diet, physical activity, smoking).
5. Examples include heart disease, stroke, cancer, diabetes, and chronic respiratory diseases.
6. They are a major cause of morbidity and mortality globally.

Teaching Methods/Instructional Techniques

Discussion, Explanation, Question and Answer, Guided Practice, Tabulation

Instructional Procedures

Step 1: Introduction

Time: 5 minutes

Teaching Skill: Eliciting/Activating prior knowledge

Teacher’s Activity: The teacher greets the students and asks them to name some things that can make people sick. The teacher then introduces the topic: Pathogens and Parasites.

Pupils’ Activity: Students respond by naming various causes of sickness and listen to the introduction.

Learning Point: Introduction to disease causes

Step 2: Definition of Pathogens

Time: 8 minutes

Teaching Skill: Explanation/Definition

Teacher’s Activity: The teacher explains the meaning of pathogens, providing a clear definition and discussing their nature as disease-causing microorganisms. The teacher also gives examples like bacteria, fungi, and rickettsia.

Pupils’ Activity: Students listen attentively, ask questions for clarification, and note down the definition and examples.

Learning Point: Meaning and examples of pathogens

Step 3: Definition of Parasites

Time: 8 minutes

Teaching Skill: Explanation/Definition

Teacher’s Activity: The teacher explains the meaning of parasites, highlighting their dependency on a host and providing examples such as helminthes and worms. The teacher may use charts to show pictures of different parasites.

Pupils’ Activity: Students listen, observe the charts, and note down the definition and examples of parasites.

Learning Point: Meaning and examples of parasites

Step 4: Examples of Pathogens and Parasites

Time: 6 minutes

Teaching Skill: Elaboration/Identification

Teacher’s Activity: The teacher guides students to recall and identify specific examples of pathogens (bacteria, fungi, rickettsia) and parasites (helminthes, worms) discussed, ensuring they understand the distinction.

Pupils’ Activity: Students actively participate by naming examples and clarifying any confusion between the two categories.

Learning Point: Specific examples identification

Step 5: Differences Between Pathogens and Parasites

Time: 7 minutes

Teaching Skill: Comparison/Tabulation

Teacher’s Activity: The teacher guides students in a discussion to identify the key differences between pathogens and parasites. The teacher then helps students tabulate these differences on the board.

Pupils’ Activity: Students contribute to the discussion, identify differences, and copy the tabulated information from the board.

Learning Point: Pathogen and parasite differences

Step 6: Characteristics of Non-Communicable Diseases

Time: 7 minutes

Teaching Skill: Explanation/Description

Teacher’s Activity: The teacher explains the characteristics of non-communicable diseases, emphasizing that they are not infectious and often linked to lifestyle factors. The teacher provides examples of NCDs.

Pupils’ Activity: Students listen and note down the key characteristics and examples of non-communicable diseases.

Learning Point: Features of non-communicable diseases

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

1. What is a pathogen? Give two examples.
2. What is a parasite? Give two examples.
3. State two differences between pathogens and parasites.
4. Mention three characteristics of non-communicable diseases.

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Understanding of lesson concepts

Step 8: Note-Taking

Time: 4 minutes

Teaching Skill: Guided Writing

Teacher’s Activity: The teacher guides pupils/students to copy the essential Board Summary notes on pathogens, parasites, their differences, and NCD characteristics into their notebooks.

Pupils’ Activity: Pupils/students copy the notes carefully into their notebooks.

Learning Point: Recording lesson information

Step 9: Conclusion

Time: 2 minutes

Teaching Skill: Summarization

Teacher’s Activity: The teacher briefly summarizes the lesson by reiterating the main points about pathogens, parasites, their differences, and the nature of non-communicable diseases, encouraging students to apply this knowledge for better health.

Pupils’ Activity: Students listen and ask any final questions.

Learning Point: Consolidation of key concepts

Continuous Assessment/Further Study

Type: Homework

Instruction: Answer the following questions in your notebook:

1. Research and list two diseases caused by bacteria and two caused by helminthes.
2. Explain why malaria is considered a parasitic disease.
3. In what ways can understanding the differences between pathogens and parasites help in preventing diseases?
4. Give three examples of non-communicable diseases prevalent in Nigeria and suggest one preventive measure for each.

Lesson Keywords

• Pathogen – A microorganism or agent that causes disease.
• Parasite – An organism that lives on or in a host and gets its food from or at the expense of its host.
• Bacteria – Single-celled microorganisms, some of which are pathogenic.
• Fungi – Organisms like moulds and yeasts, some of which are pathogenic.
• Rickettsia – A type of bacteria that causes diseases like typhus.
• Helminthes – Parasitic worms, such as tapeworms and roundworms.
• Non-communicable disease – A non-infectious disease that cannot be transmitted from person to person.

Differentiation

For slower learners, the teacher will provide simplified definitions and more visual aids, focusing on identifying basic examples of pathogens and parasites. Faster learners can be challenged to research specific diseases caused by different types of pathogens and parasites, or to discuss the global impact of non-communicable diseases.

Suggested Lesson Videos

For further understanding, students can search on YouTube for:

• “Pathogens and parasites explained”
• “Difference between pathogens and parasites”
• “Characteristics of non-communicable diseases”

Teacher Guide for Using This Lesson Plan

Before the lesson, ensure you have prepared charts or images of various pathogens (e.g., bacteria, fungi) and parasites (e.g., worms) to aid visual learning. Begin by engaging students with questions about common illnesses to activate their prior knowledge. Clearly explain the definitions of pathogens and parasites, using the provided examples. During the discussion on differences, encourage students to contribute their observations and guide them in tabulating the information. Emphasize that students should copy the Board Summary notes during Step 8. For the section on non-communicable diseases, highlight their non-infectious nature and link them to lifestyle factors. Constantly check for understanding through questions and provide support for any misconceptions. Encourage faster learners to think critically about disease prevention and control.