A Catalyst article explaining how enzymes allow chemical reactions in all living organisms to proceed quickly, under conditions where they would normally be very slow. By isolating enzymes that could be used to catalyze reactions, scientists have started a major biotechnology industry. The article describes how...

Published by the Wellcome Trust, the 'Big Picture' explores issues around biology and medicine. How do we stop new diseases emerging or re-emerging infections getting out of hand?

How does this happen in a world of...

This article looks at epigenetics in plants.

Rooted to the spot, plants cannot run away from problems.  Instead,...

From the Institute of Physics, this topic looks at basic electrical ideas, particularly current, potential difference and energy. The topic is split into teaching episodes. These are self-contained activities of varying time periods. The topics in this section include:

Episode 101:...

These activities, from the Institute of Physics, look at electrical circuits. They provide a review of previous knowledge and introduce the language needed to cope with the greater depth of learning at post-16 level. Activities include: • a discussion about electrical circuits to reinforce knowledge and highlight...

From the Institute of Physics, these activities allow students to understand the idea of electric charge and its relationship to a flow of current. There are a range of activities and these include: • using an analogy to represent the movement of charge • defining current and the coulomb • calculations to show the...

From the Institute of Physics, these activities present a range of examples involving different types of charge carrier and links the measured current to rates of flow of charge. The activities consist of a series of demonstrations which could be set up before the lesson. These include: • considering different...

From the Institute of Physics, this learning episode shows that charge carriers in good conductors usually move very slowly. It illustrates the derivation and use of the equation I = nAvq.

A range of activities include:
• viewing the movement of permanganate ions in an electric field
•...

This activity from the Institute of Physics discusses energy transfer in electric circuits and links this, by analogy, to other more familiar examples.

The activities include:
• demonstrations of human and lemon-powered batteries to illustrate that that there is nothing special about the chemical...

From the Institute of Physics, in this learning episode, students calculate electrical power and through discussion, review their understanding of: • current • potential difference • electromotive force (emf) • charge • drift velocity Students are reminded of the idea that power is the rate of doing work (or the...

This series of activities, from the Institute of Physics, help student to understand electrical resistance. What is resistance, how it can be measured, how it arises and what affects it? During the topic, resistance is related to current, voltage, type of material, temperature and light intensity. The electrical...

From the Institute of Physics, this learning episode provides a quantitative definition for resistance (R = V / I) which reinforces the qualitative notion that more resistance means less current. It looks at Ohm’s law, describing that this is not the same thing as the definition of resistance.

Activities...

Produced by the Institute of Physics, in this practical investigation students measure the current and voltage characteristics for several components and identify ohmic and non-ohmic behaviour. Students determine the V-I characteristics for: • a carbon resistor • semiconductor diode • a filament lamp In addition,...

From the Institute of Physics, this learning episode looks at the resistance of a metal and a semiconductor, giving a microscopic explanation of how resistance can vary with temperature. There is also a brief look at superconductivity and its applications.