Energy (Cambridge (CIE) A Level Biology): Revision Note

Exam code: 9700

Phil

Written by: Phil

Reviewed by: Alistair Marjot

Updated on

The need for energy

  • Living organisms are composed of cells, and within each cell, many activities and processes are constantly being carried out to maintain life

    • Work in a living organism requires energy

Type of work

Examples

Transporting substances across membranes

  • Active transport using the sodium-potassium pump in cell membranes

  • Exocytosis of digested bacteria from white blood cells

Anabolic reactions

  • Synthesis of DNA from nucleotides

  • Synthesis of proteins from amino acids

Movement

  • Cellular movement of chromosomes via the spindle

  • Mechanical contraction of muscles

Maintaining body temperature

  • Occurs only in mammals and birds

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Phil

Author: Phil

Expertise: Biology Content Creator

Phil has a BSc in Biochemistry from the University of Birmingham, followed by an MBA from Manchester Business School. He has 15 years of teaching and tutoring experience, teaching Biology in schools before becoming director of a growing tuition agency. He has also examined Biology for one of the leading UK exam boards. Phil has a particular passion for empowering students to overcome their fear of numbers in a scientific context.

Alistair Marjot

Reviewer: Alistair Marjot

Expertise: Environmental Systems and Societies & Biology Content Creator

Alistair graduated from Oxford University with a degree in Biological Sciences. He has taught GCSE/IGCSE Biology, as well as Biology and Environmental Systems & Societies for the International Baccalaureate Diploma Programme. While teaching in Oxford, Alistair completed his MA Education as Head of Department for Environmental Systems & Societies. Alistair has continued to pursue his interests in ecology and environmental science, recently gaining an MSc in Wildlife Biology & Conservation with Edinburgh Napier University.