GCSE Applied Science WJEC

Energy and Life

Energy and Life

Understanding Energy

• Energy is the ability to do work, it cannot be created or destroyed but can be transferred or transformed.

• Different forms of energy include kinetic, potential, chemical, thermal, electric, magnetic, eleastic, nuclear, light, and sound energy.

• Many life processes involve the transformations and transfers of energy.

Energy Flows in Ecosystems

• Energy enters ecosystems as radiant energy from the sun.

• Producers like plants convert solar energy into chemical energy through photosynthesis. This energy is stored in plant tissues.

• Consumers gain energy by feeding on producers or other consumers.

• Each transfer of energy from one trophic level to the next involves losses, primarily as heat.

Understanding Respiration

• Respiration is a process in living organisms involving the production of energy, usually with the intake of oxygen and the release of carbon dioxide.

• It involves the oxidation of food molecules like glucose to release energy, water, and carbon dioxide.

• Aerobic respiration requires oxygen and produces a large amount of energy.

• Anaerobic respiration does not require oxygen and occurs when there is insufficient oxygen available. It results in lactic acid or alcohol and yields less energy.

Importance of Energy in Living Organisms

• Energy is required for various biological processes including active transport, building and repair of tissues, movement, and maintaining body temperature.

Energy Efficiency and Conservation

• Energy efficiency specifies how much useful work is achieved before energy dissipation.

• Improving energy efficiency and conservation are key strategies to reduce energy waste.

• In natural ecosystems, large amounts of energy are lost between trophic levels, thus limiting the number of trophic levels in a food web.

Impact of Human Activity on Ecosystem energy flow

• Human activities such as deforestation and burning fossil fuels can disrupt energy flow in ecosystems and contribute to climate change.

• Protecting and conserving natural resources, and using renewable energy sources can help mitigate human impact on the environment.