A Level Biology: It’s Not Just Learning — It’s Applying

A Level Biology can feel overwhelming. There are pages of content, complex terminology, and diagrams that seem to multiply overnight.

But here’s the truth I remind my students of every week:

Success in A Level Biology isn’t about how much you can memorise… it’s about how well you can apply what you know.

After 40 years of teaching, I’ve seen students who “know everything” struggle—and others who understand how to use their knowledge achieve top grades.

So how do you make that shift?

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1. Move from Passive to Active Learning

Reading notes or watching videos is not enough.

You need to do something with the information.

✔ Close the book and write everything you remember
✔ Draw diagrams from memory
✔ Explain it out loud (even better—teach someone else)

 If you can’t explain it simply, you don’t fully understand it.

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2. Use Retrieval Practice (The Game Changer)

This is one of the most powerful techniques.

Instead of rereading notes:

• Test yourself regularly
• Use flashcards
• Write answers to questions without notes

Your brain strengthens pathways when it retrieves information—not when it rereads it.

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3. Practise Applying Knowledge to New Contexts

Exam questions are rarely straightforward.

They often:

• Combine topics
• Use unfamiliar scenarios
• Expect interpretation of data

So practise:

• Past paper questions
• Data analysis (graphs, tables, experiments)
• “Explain why” and “suggest how” questions

This is where top grades are won.

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4. Master Exam Technique (It’s a Skill!)

Many students lose marks not because they don’t know the content—but because they don’t answer the question properly.

Focus on:

• Command words (describe, explain, evaluate)
• Using key terminology precisely
• Structuring answers clearly

A 3-mark question usually needs 3 clear points—not a paragraph of waffle.

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5. Make Connections Between Topics

Biology is not a set of isolated facts.

For example:

• Enzymes → Digestion → Respiration
• DNA → Protein synthesis → Genetic disorders
• Cell membranes → Transport → Nerve impulses

The more connections you make, the easier it becomes to apply knowledge in unfamiliar questions.

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6. Understand Practicals (Not Just Follow Them)

Required practicals are a goldmine for exam questions.

Make sure you can:

• Explain the method
• Identify variables (independent, dependent, control)
• Evaluate errors and suggest improvements

💡xaminers love asking: “How could this experiment be improved?”

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7. Use Structured Revision Tools

Some of the most effective tools I use with my students:

• Flashcards (definitions + processes)
• Mind maps (linking topics)
• Summary sheets (one topic per page)
• Practice question folders

Keep it organised—your future self will thank you!

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Final Thought

A Level Biology is not about memorising a textbook.

It’s about:
✔ Understanding
✔ Connecting ideas
✔ Applying knowledge to new situations

Master that—and the grades will follow.

 

Learning About Autism from an Expert – My Son

There are some lessons that no textbook, no specification, and no exam board can truly capture.

Today was one of those lessons.

As part of our psychology sessions, my students had the opportunity to learn about autism—not from a diagram, not from a case study—but from someone living it every day: my son.

At 32, he has what many would describe as “high-functioning” autism. Labels aside, what he offered the students was something far more valuable—authentic insight.

What the Students Noticed First

It didn’t take long for the students to pick up on something.

He didn’t make eye contact.

In a classroom, that stands out immediately. We are so conditioned to see eye contact as a sign of attention, confidence, and engagement.

But this sparked one of the most powerful learning moments of the session:

Eye contact can be uncomfortable, distracting, or even overwhelming for someone with autism.

What might seem “normal” to one person can feel very different to another.

Understanding, Not Judging

Rather than explaining autism in abstract psychological terms, the students experienced it through conversation.

They began to understand:

• Communication differences are not deficits—they are differences
• Social interaction isn’t one-size-fits-all
• Behaviour always has a reason, even if we don’t immediately understand it

This is something exam answers often miss. Psychology is not just about definitions—it’s about people.

Strategies for Coping

One of the most valuable parts of the session was hearing about the strategies he has developed over time.

These included:

• Learning when and how to engage socially
• Developing routines to reduce anxiety
• Finding ways to manage sensory overload
• Being open about needing time or space

These are not weaknesses—they are tools for success.

For the students, this reframed autism completely. Instead of seeing challenges, they saw adaptation, resilience, and problem-solving.

A Lesson That Will Stay With Them

As a teacher, I can explain theories such as:

• The triad of impairments
• Theory of mind
• Cognitive explanations of autism

But today, those theories came alive.

This wasn’t just a lesson for an exam.

It was a lesson in empathy, understanding, and seeing the world through someone else’s eyes.

And I suspect it’s one they won’t forget.

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A Personal Reflection

As both a teacher and a parent, today meant a great deal.

Watching my students listen, question, and reflect—and watching my son share his experiences so openly—was something quite special.

Education works best when it connects knowledge with real life.

Today, it truly did.

Computing: SSD vs SD Cards – How Do They Actually Work?

 

SSD vs SD Cards – How Do They Actually Work?

And why both are essential in modern computing

Walk into any classroom, studio, or sailing trip with cameras, and you’ll find both SSDs and SD cards quietly doing the same job: storing data.

But how do they actually work? And why do we need both?

Let’s take a look under the hood.

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 The Key Idea: No Moving Parts

Unlike old hard drives (HDDs), SSDs and SD cards store data electronically using flash memory.

That means:

• No spinning disks

• No moving read/write heads

• Faster, quieter, more reliable storage

Perfect for:

• Laptops

• Cameras (very relevant for sailing videos!)

• Smartphones

• Lab data logging systems

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 What Is Flash Memory?

At the heart of both SSDs and SD cards is NAND flash memory.

Think of it as:

• Millions (or billions!) of tiny switches

• Each switch stores a bit (0 or 1)

• Data is stored by trapping electrical charge

Simple analogy:

Imagine a grid of tiny buckets:

• Bucket full → 1

• Bucket empty → 0

These “buckets” are actually floating gate transistors that can hold charge even when power is off.

👉 That’s why your data stays saved when the device is turned off.

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 How an SSD Works

An SSD is much more than just memory chips.

It contains:

• NAND flash memory (storage)

• Controller chip (the brain)

• Cache (sometimes DRAM)

The controller does the clever work:

• Decides where to store data

• Manages wear (important!)

• Retrieves data quickly

• Corrects errors

Key concept: Wear Levelling

Flash memory wears out after many writes.

So the SSD:

• Spreads data evenly across cells

• Prevents any one area wearing out too quickly

This is why SSDs last much longer than you might expect.

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 How an SD Card Works

An SD card is essentially a miniature SSD.

Inside that tiny plastic case:

• NAND flash memory

• A small controller

The differences:

• Simpler controller (less powerful than SSDs)

• Smaller size

• Designed for portability

Why they’re perfect for cameras:

• Lightweight

• Removable

• Low power consumption

👉 Ideal for your sailing videos, drones, and portable experiments.

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Why SSDs Are Faster Than SD Cards

Even though they use similar technology:

Feature	SSD	SD Card
Controller	Advanced	Basic
Speed	Very fast (GB/s)	Slower (MB/s)
Use case	Computers	Cameras & portable devices
Durability	High	Good

Real-world example:

• SSD → Editing 4K video smoothly

• SD card → Recording the footage in the first place

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 A Teaching Insight

This topic links beautifully across subjects:

• Physics → Electron charge and semiconductors

• Computer Science → Data storage and binary

• Engineering → Reliability and system design

It’s a great example of applied science in everyday life.

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Limitations to Know

Even modern flash storage isn’t perfect:

• Limited write cycles

• Can fail suddenly (no warning like HDD noise!)

• Data recovery is harder

👉 Always back up important files (especially those sailing videos!)

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 Final Thoughts

SSDs and SD cards may look very different, but at their core:

➡️ They both store data using trapped electrical charge
➡️ They both rely on clever controllers
➡️ They’ve revolutionised computing and media

From your lab experiments to your camera on a windy day at UTSC, these tiny devices are doing an extraordinary job.

 

Using IR Spectroscopy to Identify Substances (A-Level Chemistry)

What is IR Spectroscopy?

Infrared (IR) spectroscopy is one of those beautifully simple yet powerful techniques in chemistry. Instead of looking at what something looks like, we look at how its bonds vibrate when exposed to infrared radiation.

Every bond in a molecule absorbs IR radiation at a specific frequency, giving us a unique fingerprint of the substance.

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What Does an IR Spectrum Look Like?

An IR spectrum is a graph of:

• Wavenumber (cm⁻¹) on the x-axis

• Transmittance (%) on the y-axis

Dips in the graph show where radiation is absorbed.

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The Key Idea: Bond Vibrations

When IR radiation hits a molecule:

• Bonds stretch and bend

• Each type of bond absorbs at a different frequency

Think of bonds like springs:

• Stronger bonds → higher frequency

• Heavier atoms → lower frequency

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The Important Regions to Learn

1. The Functional Group Region (4000–1500 cm⁻¹)

This is where most of your identification marks come from in exams.

Key peaks to remember:

Bond	Wavenumber (cm⁻¹)	Shape
O–H (alcohol)	3200–3600	Broad
N–H	3300	Medium
C–H	2800–3000	Sharp
C=O	~1700	Strong & sharp

👉 If you see a broad peak around 3300 cm⁻¹, think alcohol immediately.

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2. The Fingerprint Region (1500–500 cm⁻¹)

• Complex and messy

• Unique to each compound

• Used to confirm identity by comparison with known spectra

👉 In exams, you rarely analyse this in detail — but it’s crucial in real chemistry.

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Worked Example

Question: Identify the functional group from this IR data:

• Broad peak at 3300 cm⁻¹

• No peak at 1700 cm⁻¹

Answer:

• Broad 3300 → O–H present

• No 1700 → no C=O

✅ Substance is likely an alcohol

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Exam Tips (AQA / OCR / Edexcel)

• Always quote wavenumbers in your answer

• Use key words:

  • “broad peak”

  • “sharp peak”

  • “strong absorption”

• Link peak → bond → functional group

👉 A 2–3 mark question is often just:

“Peak at 1700 cm⁻¹ indicates C=O, therefore a carbonyl compound.”

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Common Mistakes

• ❌ Confusing O–H and N–H (O–H is broader)

• ❌ Forgetting units (cm⁻¹)

• ❌ Ignoring absence of peaks (just as important!)

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Why IR Spectroscopy Matters

In real labs, IR is used to:

• Identify unknown compounds

• Check purity

• Support other techniques like NMR and mass spectrometry

It’s quick, reliable, and a cornerstone of analytical chemistry.

 

Demonstrating the Heating Effect of Electricity Passing Through a Wire

One of the simplest but most important ideas in electricity is that when an electric current passes through a wire, the wire can get hot. We rely on this every day, even if we do not think about it very often. Kettles, toasters, electric heaters, hairdryers and even old-style filament lamps all depend on the heating effect of electricity.

In a school laboratory, this effect can be demonstrated very clearly and it gives students a practical way to connect ideas such as current, resistance, power and energy transfer.

At first glance, a wire may just look like a passive path for electricity, but that is not really what is happening. The electrons move through the metal, colliding with the vibrating ions in the lattice of the material. These collisions transfer energy to the wire and increase its temperature. In other words, electrical energy is being converted into thermal energy.

A very simple demonstration can be done using a length of resistance wire, such as nichrome, connected to a low-voltage power supply. As the current increases, the wire begins to warm up. With the correct wire and suitable power settings, it may even start to glow faintly red. That moment is always memorable for students because they can see that electricity is not some abstract idea hidden inside equations. It is doing something very real.

The choice of wire matters. Ordinary copper wire has a very low resistance, so it does not heat up as dramatically in a simple classroom demonstration unless very large currents are used, which would be unsafe. Resistance wire is much better because it has a higher resistance, so more energy is transferred as heat for a given current.

This demonstration also helps explain the equation:

Power = current² × resistance

So if the current is doubled, the heating effect does not just double, it increases much more rapidly. That is why thin wires, or wires carrying too much current, can become dangerously hot. It also explains why fuses are designed to melt when the current becomes too large. They protect circuits by making use of the heating effect.

Students can take the experiment further by changing one factor at a time. What happens if the wire is made longer? What happens if a thicker wire is used? What difference does the material make? These are excellent questions because they lead directly into the idea that resistance depends on length, cross-sectional area and material.

There is also a useful link here to everyday life. Why does a kettle element get hot while the flex leading to it usually stays cool? The answer lies in resistance. The heating element is designed to have enough resistance to transfer electrical energy efficiently into heat, while the connecting wires are designed to have very low resistance so that as little energy as possible is wasted.

Of course, safety matters in any such demonstration. Wires can become hot enough to burn skin, melt insulation or damage equipment. Power supplies should be used within safe limits, the wire should be mounted securely, and students should be warned not to touch the wire until it has cooled. Eye protection is sensible, and the demonstration should always be supervised carefully.

What I like about this practical is that it bridges theory and reality beautifully. Students meet ideas like current, resistance and power in textbooks, but when they actually see a wire heating up, the topic becomes much more tangible. It is a reminder that physics is not just about symbols on a page. It is about understanding the hidden processes behind the devices we use every day.

The heating effect of electricity may sound like a small idea, but it underpins a huge part of modern life. From cooking dinner to staying warm to protecting electrical circuits, it is one of those principles that quietly powers the world around us.

 

Why Mathematical Series Are So Important

Mathematical series appear everywhere in mathematics, physics, engineering, and even finance. At first glance they can look like nothing more than long lists of numbers added together, but in reality they are one of the most powerful tools mathematicians have ever developed. From calculating areas to predicting population growth and modelling waves, series quietly sit behind many of the formulas we use every day.

What is a Series?

A series is what we get when we add together the terms of a sequence.

For example, a simple arithmetic series might look like this:

1 + 2 + 3 + 4 + 5 + …

The series is the sum of the sequence. Sometimes the number of terms is finite, and sometimes it continues forever (an infinite series).

Series allow mathematicians to break complicated problems into many small pieces that can be added together.

The Famous Geometric Series

One of the most useful series is the geometric series, where each term is multiplied by a constant ratio.

$$1 + r + r^2 + r^3 + \dots = \frac{1}{1-r} \quad (|r|<1)$$

This remarkable result shows that an infinite series can actually add up to a finite number.

For example:

1/2 + 1/4 + 1/8 + 1/16 + …

adds up to exactly 1.

This idea is fundamental in many areas of science, including signal processing, electrical circuits, and probability theory.

Approximating the Impossible

Series are incredibly powerful because they allow us to approximate complicated functions.

For example, the famous exponential function can be written as a series:

$$e^x = 1 + x + \frac{x^2}{2!} + \frac{x^3}{3!} + \dots$$

This means computers can calculate complex functions by simply adding many terms together. In fact, many calculators and computer algorithms rely on series expansions behind the scenes.

Physics, Engineering and the Real World

Series appear throughout science.

In physics they are used to:

• Approximate motion

• Model waves

• Calculate electric fields

• Solve differential equations

In engineering they help model:

• vibrations

• electrical signals

• structural loads

Even in finance, compound interest calculations are closely related to exponential series.

A Tool for Simplifying Difficult Problems

One of the key reasons series are so powerful is that they allow difficult problems to be turned into simpler ones.

Instead of solving one complicated equation, mathematicians break the problem into an infinite set of small steps, each of which can be calculated.

This idea underpins many branches of mathematics including:

• calculus

• Fourier analysis

• numerical modelling

• quantum physics

Final Thought

Series are one of those ideas that seem abstract when first encountered in mathematics lessons. Yet they are one of the hidden engines of modern science and technology.

From the way computers calculate functions to how physicists model the universe, series allow us to turn complexity into manageable mathematics.

And that is why they are so important.

 

Internal Resistance – What It Is, How We Measure It, and Why It Matters

In school physics we often treat power supplies and batteries as if they provide a perfect, constant voltage. In reality, every battery and power supply has something hidden inside it called internal resistance.

Understanding this idea is crucial for GCSE and A-Level Physics, because it explains why the voltage of a battery drops when we draw current from it.

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What is Internal Resistance?

Inside every cell or battery there are materials that resist the movement of charge. This resistance is caused by:

• The electrolyte in the cell

• The electrodes and internal wiring

• Chemical reactions occurring inside the battery

This means that some of the electrical energy supplied by the battery is lost as heat inside the battery itself.

Because of this, the voltage available to the external circuit is less than the battery’s emf.

The relationship is given by the well-known equation:

V = 𝓔 − Ir

Where:

• V = terminal potential difference across the circuit

• 𝓔 (emf) = electromotive force of the battery

• I = current

• r = internal resistance

As the current increases, the voltage lost inside the battery (Ir) increases.

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Why Does Voltage Drop When You Use a Battery?

If you connect a battery to a device:

1. Current flows through the external circuit.

2. The same current must also pass through the battery’s internal resistance.

3. Energy is lost inside the battery as heat.

So the voltage you measure across the terminals becomes:

Terminal voltage = emf − voltage lost internally

This is why a battery that reads 1.5 V when unused might drop to 1.3 V when powering a motor or lamp.

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Measuring Internal Resistance in the Lab

One of the most useful school experiments measures internal resistance directly.

Equipment needed

• Power supply or cell

• Voltmeter

• Ammeter

• Variable resistor (or rheostat)

• Switch

• Connecting wires

Method

1. Connect the circuit with the ammeter in series and voltmeter across the cell.

2. Use the variable resistor to change the current in the circuit.

3. Record several pairs of readings of current (I) and terminal voltage (V).

Typical results look something like this:

Current (A)	Voltage (V)
0.10	1.48
0.20	1.46
0.30	1.43
0.40	1.39

As the current increases, the voltage falls.

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Using a Graph to Find Internal Resistance

Plot a graph of:

Terminal Voltage (V) vs Current (I)

You obtain a straight line with a negative gradient.

From the equation:

V = 𝓔 − Ir

• The y-intercept = emf (𝓔)

• The gradient = −r

So:

Internal resistance = − gradient of the graph

This is a beautiful example of physics linking theory, experiment, and graph analysis.

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Why Internal Resistance Is So Important

Internal resistance affects many real-world technologies:

1. Batteries in phones and laptops
As batteries age, internal resistance increases. This is why older batteries discharge quickly.

2. Electric vehicles
Battery efficiency depends heavily on keeping internal resistance low.

3. High-current devices
Things like motors or heating elements draw large currents, which can cause large voltage drops.

4. Power losses
Energy lost inside a battery becomes heat, reducing efficiency.

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A Simple Demonstration for Students

A good classroom demonstration is to:

1. Measure the open-circuit voltage of a battery.

2. Connect a small motor or lamp.

3. Measure the voltage again.

Students immediately see the voltage drop under load, making internal resistance very real.

Using sensors such as PASCO current and voltage probes, you can even capture the data live and plot the graph instantly.

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Final Thought

Internal resistance reminds us that real electrical systems are never perfect.

Every battery, from a small AA cell to the massive batteries in electric cars, loses some energy internally. Understanding this helps physicists and engineers design more efficient power systems.

And it also explains why your phone battery seems to struggle when it gets old!