Class: Senior Secondary School 1 (SS1, SS 1, SSS1, SSS 1)
Term: 1st Term
Week: 9
Age: 15 years
Duration: 45 minutes
Subject: Biology
Curriculum Theme: Biology
Previous Lesson: Excretion.
Topic: GROWTH.
Subject Matter: Basis of growth (cell division – mitosis, cell enlargement and differentiation), regulation of growth by hormones, examples of animal hormones, measurement of growth (height, weight, dry mass, and size).

Specific Objectives

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

Cognitive Domain:

Define growth.
Explain the role of cell division (mitosis) in growth.
State how cell enlargement and differentiation contribute to growth.
List examples of animal hormones that regulate growth.
Mention ways to measure growth.

Affective Domain:

Appreciate the importance of hormones in regulating growth.
Value accurate measurement of growth in living organisms.

Psychomotor Domain:

Measure height and weight using appropriate instruments.
Observe diagrams illustrating the stages of mitosis.

Collaborate effectively in groups to carry out growth measurements.

Reference Materials

The following resources were used in planning this lesson:

9 Years Basic Education Curriculum for Biology. https://www.nerdc.gov.ng/
State Unified Scheme of Work for Biology SSS 1. https://www.myschoolgist.com/
Modern Biology for Senior Secondary Schools by Ramalingam.
Biology Textbook for Senior Secondary Schools.

Instructional Materials

The teacher will teach this lesson with the aid of:

Measuring tape
Weighing scale
Growth chart
Diagrams of mitosis stages

Rationale for the Lesson

This lesson helps pupils understand how living organisms increase in size and complexity. It enables pupils to grasp the fundamental processes of cell division and the regulatory roles of hormones, which are essential for understanding human development and health.

Prerequisite/Previous Knowledge

Pupils have prior knowledge of the cell as the basic unit of life and can identify basic cell structures.

Lesson Content/Board Summary

GROWTH

Definition of Growth

Growth is defined as an irreversible increase in the size, mass, and complexity of an organism or its parts.

Basis of Growth: Cell Division (Mitosis)

Mitosis is a type of cell division that results in two daughter cells, each having the same number and kind of chromosomes as the parent nucleus. It is the primary process responsible for increasing the number of cells in an organism, thus leading to growth.

Cell Enlargement and Differentiation

Cell enlargement involves an increase in the volume and size of individual cells after they have divided. Cell differentiation is the process by which a less specialized cell becomes a more specialized cell type, contributing to the formation of different tissues and organs.

Regulation of Growth by Hormones

Hormones are chemical messengers produced by endocrine glands that regulate various physiological processes, including growth. They control the rate and pattern of growth by stimulating or inhibiting cell division, enlargement, and differentiation.

Examples of Animal Hormones Regulating Growth

The following are examples of animal hormones that regulate growth:

Growth Hormone (GH): Produced by the pituitary gland, it stimulates overall body growth, especially in bones and muscles.
Thyroxine: Produced by the thyroid gland, it is essential for normal growth and development, particularly of the nervous system.
Insulin: Produced by the pancreas, it helps in the uptake and utilization of glucose by cells, which is necessary for energy and growth.
Testosterone: A male sex hormone, it promotes muscle and bone growth during puberty.
Estrogen: A female sex hormone, it plays a role in bone growth and development of female secondary sexual characteristics.

Measurement of Growth

Growth can be measured using various parameters:

Height: Measured using a measuring tape or stadiometer.
Weight: Measured using a weighing scale.
Dry Mass: The mass of an organism after all water has been removed.
Size: Can refer to length, width, or volume.

Teaching Methods/Instructional Techniques

Discussion, Lecture, Demonstration, Question and Answer, Visual Aids

Instructional Procedures

Step 1: Introduction

Time: 5 minutes
Teaching Skill: Set Induction/Prior Knowledge Activation
Teacher’s Activity: The teacher greets the pupils and asks questions about what they understand by an increase in size in living things, relating it to their own growth. The teacher then introduces the topic “Growth”.
Pupils’ Activity: Pupils respond to the teacher’s questions and listen attentively to the introduction.
Learning Point: Pupils are prepared for the lesson and understand the relevance of growth.

Step 2: Explanation of Growth and Cell Division

Time: 10 minutes
Teaching Skill: Explanation/Illustration
Teacher’s Activity: The teacher defines growth and explains how cell division, specifically mitosis, leads to an increase in cell number. The teacher uses diagrams of mitosis stages to illustrate the process.
Pupils’ Activity: Pupils listen, observe the diagrams, ask questions, and take notes.
Learning Point: Pupils understand the definition of growth and the role of mitosis.

Step 3: Cell Enlargement and Differentiation

Time: 7 minutes
Teaching Skill: Explanation/Elaboration
Teacher’s Activity: The teacher explains cell enlargement as the increase in cell size and differentiation as the process of cells specializing for different functions, linking these to the overall growth and development of an organism.
Pupils’ Activity: Pupils listen and contribute to the discussion.
Learning Point: Pupils understand how cells grow in size and specialize.

Step 4: Regulation of Growth by Hormones

Time: 7 minutes
Teaching Skill: Explanation/Concept Mapping
Teacher’s Activity: The teacher explains that hormones are chemical messengers that regulate growth and development. The teacher describes how hormones stimulate or inhibit growth processes.
Pupils’ Activity: Pupils listen, ask questions, and grasp the concept of hormonal regulation.
Learning Point: Pupils understand that hormones control growth.

Step 5: Examples of Animal Growth Hormones

Time: 5 minutes
Teaching Skill: Listing/Examples
Teacher’s Activity: The teacher lists and briefly explains examples of animal hormones (e.g., Growth Hormone, Thyroxine, Insulin) and their roles in regulating growth.
Pupils’ Activity: Pupils listen, take notes, and identify key growth hormones.
Learning Point: Pupils can name and describe functions of animal growth hormones.

Step 6: Measurement of Growth

Time: 6 minutes
Teaching Skill: Demonstration/Practical Application
Teacher’s Activity: The teacher demonstrates how to measure height and weight using a measuring tape and weighing scale. The teacher guides a few pupils to practice these measurements and discusses other methods like dry mass and size.
Pupils’ Activity: Pupils observe, participate in measurements, and record values.
Learning Point: Pupils learn practical ways to measure growth.

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

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

Define growth.
State the role of mitosis in the growth of an organism.
Mention two animal hormones that regulate growth.
List two ways to measure growth.

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Pupils demonstrate understanding of the lesson.

Step 8: Conclusion

Time: —
Teaching Skill: Summarization
Teacher’s Activity: The teacher summarizes the key points of the lesson, emphasizing the importance of cell division, enlargement, differentiation, and hormones in growth. The teacher assigns homework: Research on plant growth hormones.
Pupils’ Activity: Pupils listen to the summary and copy the homework.
Learning Point: Pupils reinforce their understanding and are aware of follow-up tasks.

Lesson Keywords

Growth – An irreversible increase in the size, mass, and complexity of an organism.
Mitosis – A type of cell division that results in two daughter cells with the same number of chromosomes as the parent cell.
Hormones – Chemical messengers that regulate physiological processes, including growth.
Differentiation – The process by which a cell becomes specialized.
Cell Enlargement – Increase in the size or volume of an individual cell.

Differentiation

For pupils who grasp concepts quickly, the teacher can challenge them to explain the differences between growth in animals and plants. For pupils who require more support, the teacher can provide simplified diagrams and allow for peer-assisted learning during practical measurement activities.

Note for teachers using this lesson plan

Teachers should ensure all instructional materials, especially the measuring tape and weighing scale, are available and in good working condition before the lesson. Encourage active participation during the demonstration of growth measurement. Ensure pupils understand the link between cellular processes and the macroscopic observation of growth.