lesson
Magnification is not the same as detail
1 · Learn
A light microscope makes small structures appear larger. Total magnification is commonly the eyepiece magnification multiplied by the objective magnification. A larger image does not always resolve more detail if the instrument cannot distinguish nearby points.
A biological drawing should record visible features clearly and include labels and a scale or magnification where appropriate. Do not copy imaginary organelles into a drawing when they are not visible in the specimen.
2 · Worked example
A ×10 eyepiece with a ×40 objective gives ×400 magnification. That number does not prove every organelle is visible.
3 · Your turn
What is the total magnification for ×10 and ×4 lenses? Should you draw an unseen chloroplast as an observation?
Check your answer
×40. No; distinguish observed structures from information supplied by a model or reference.
4 · Apply your learning
Use a prepared micrograph to draw visible structures, then compare it with a labelled model and note the differences.
Adult guidance and safety
Use supplied data and diagrams unless a qualified adult has approved the practical, equipment and risk assessment. No tasting substances, culturing unknown microbes, mains electricity, flames or hazardous chemical experiments at home. Models simplify reality; ask which assumptions affect the conclusion.
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Check a calculation · Year 5 onward
Use this only when your teacher or adult allows a calculator for the task. Show your thinking first. It does not replace mental or written arithmetic and does not mark your lesson answer.
Powers, roots and trigonometry · Year 7 onward
Use only when the task allows a calculator. Choose one operation at a time and record your working. Trigonometry here always uses degrees (DEG), not radians. Inverse sine, cosine and tangent return an angle, not a reciprocal. Keep exact fractions and π in answers when requested.
Approximate numerical results use up to 12 significant digits. Inverse sine returns −90° to 90°, inverse cosine 0° to 180°, and inverse tangent −90° to 90°; these are principal values, not every possible solution of a trigonometric equation.
My observation notebook
Follow your teacher's approved method and safety instructions. Record the sample or supplied dataset, conditions, measurements with units and uncertainties where appropriate. Distinguish observations from explanations. A described experiment is not permission to carry it out; do not improvise equipment or invent missing results.
Ask your teacher for support with the method and recording. A prediction is what you think might happen; an observation is what you actually see, hear or feel safely.
Keep your notebook: use Download notebook before leaving. Nothing is sent to the website or saved to your account. Reopen the downloaded notebook here to add another day's record. Do not include names, addresses or other private information.
Your records on this page
No observations recorded yet. Look first, then add one.
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