Lesson Notes By Weeks and Term v4 - SHS 1
BIOLOGY AS THE SCIENCE OF LIFE
Download the Lessonotes Mobile Ghana app for faster lesson access on Android and iPhone.
BIOLOGY AS THE SCIENCE OF LIFE
Download the Lessonotes Mobile Ghana app for faster lesson access on Android and iPhone.
Subject: Biology
Class: SHS 1
Term: 1st Term
Week: 3
Grade code: 1.1.1.LI.2
Strand code: 1
Sub-strand code: 1
Content standard code: 1.1.1.CS.4
Indicator code: 1.1.1.LI.2
Theme: EXPLORING BIOLOGY IN SOCIETY
Subtheme: BIOLOGY AS THE SCIENCE OF LIFE
This page supports the lesson note with a companion video and a short classroom-ready summary.
For class groups and homework, share this lesson page so learners also get the summary, objectives, and full lesson context.
Biology is the study of life, but much of life is too small to see with our naked eyes. Imagine trying to understand why someone has malaria without being able to see the parasite in their blood, or why our kenkey sometimes spoils without seeing the tiny fungi and bacteria responsible. The microscope is the biologist's most essential tool; it opens up a hidden world of cells, microorganisms, and tiny structures. In this lesson, we will learn not just what a microscope is, but how to handle it safely and use it effectively to become true scientific observers.
A. What is a Microscope? A microscope is a scientific instrument that uses lenses to make very small objects appear larger, allowing us to see details that are otherwise invisible to the naked eye. The type we will use in our laboratory is called a Compound Light Microscope. "Compound" means it uses more than one lens (an eyepiece lens and an objective lens). "Light" means it uses a light source (like a mirror or an electric lamp) to illuminate the object we are viewing. B. Parts of a Compound Light Microscope and their Functions
It is helpful to group the parts by their function: Structural, Optical, Illumination, and Focusing parts.
| Part Name | Group | Function | | -------------------------- | ------------ | -------------------------------------------------------------------------------------------------------- | | Eyepiece (Ocular Lens) | Optical | The lens you look through at the top of the microscope. It usually has a magnification of 10x or 15x. | | Objective Lenses | Optical | Lenses attached to the revolving nosepiece. They come in different powers (e.g., 4x, 10x, 40x). | | Revolving Nosepiece | Structural | A rotating turret that holds the objective lenses. You turn it to switch between different magnifications. | | Body Tube | Structural | Connects the eyepiece to the objective lenses. | | Arm | Structural | Connects the head of the microscope to the base. You use this part to carry the microscope. | | Base | Structural | The bottom support of the microscope. It provides stability. | | Stage | Structural | The flat platform where you place the slide for observation. It has a hole to let light pass through. | | Stage Clips | Structural | Metal clips that hold the slide firmly in place on the stage. | | Diaphragm (or Iris) | Illumination | A rotating disc under the stage that controls the amount of light reaching the specimen. | | Light Source (or Mirror) | Illumination | Provides light to pass through the specimen. It can be a mirror to reflect ambient light or an electric bulb. | | Coarse Adjustment Knob | Focusing | The larger knob used for initial, rough focusing, especially with the low-power objective lens. | | Fine Adjustment Knob | Focusing | The smaller knob used for sharp, precise focusing, especially with the high-power objective lens. |
![Diagram of a labelled microscope would be presented here on the board/projector] C. Safe Handling and Usage of the Microscope